From owner-chemistry@ccl.net Tue Dec 6 00:41:01 2005 From: "Brian Salter-Duke b_duke(0)octa4.net.au" To: CCL Subject: CCL: question on molecular orbitals in CO and NO Message-Id: <-30201-051205162348-30366-8jw26Kxcgumhn/98xH6KSQ]_[server.ccl.net> X-Original-From: Brian Salter-Duke Content-Disposition: inline Content-Type: text/plain; charset=us-ascii Date: Tue, 6 Dec 2005 08:23:18 +1100 Mime-Version: 1.0 Sent to CCL by: Brian Salter-Duke [b_duke^octa4.net.au] On Mon, Dec 05, 2005 at 02:21:09AM -0500, Ulrike Salzner salzner|a|fen.bilkent.edu.tr wrote: > Sent to CCL by: Ulrike Salzner [salzner%fen.bilkent.edu.tr] > Not claiming that I have a final answer to problem of the meaning of > orbitals, I would like to contribute two arguments to the discussion: > > The first is regarding the fact that orbitals can be transformed > without changing the total wavefunction. While this is correct, it is > also true that the orbital energies are not invariant under unitary > transformations. For example, the two spatially and energetically > different lone pairs (p and sp2) of the water molecule can be > transformed into two identical sp3 hybrids without changing the electron > density. However, the PE spectrum shows two peaks for the lone pairs, > one sharp and one with a vibrational progression at higher energy. > Therefore, I believe that the argument that orbitals are not unique is > false. Only canonical orbitals can be used to interpret PE spectra. > Likewise Koopmans's theorem holds only for canonical orbitals. Moreover, > localization of orbitals is only possible for certain molecules that > fullfill Hund's localization criterium. These things were discussed > nicely by Werner Kutzelnigg, Angew. Chem. Int. Ed. Engl. 1973, 12, > p.546-562. It is certainly correct that canonical orbitals for closed shell molecules are special in the sense that the matrix [phi-i anf phi-j are the molecular orbitals, possibly after a unitary transformation, and F is Fock operator.] is diagonal with the orbital energies being the diagonal terms. We can not talk baout orbital energies for other cases. Koopman's theorem holds only for canonical orbitals, I agree, but only for closed shell molecules. Koopman;s theorem is an approximation for predicting PES. It says that the negative of the orbital energy is the Hartree-Fock prediction of the ionisation energy > from that orbital if the orbitals in the ion after ionisation are the same as those in the molecule. That is, relaxation of the orbitals is not taken into account. Since it is the Hartree-Fock prediction, correlation is not taken into account. Where Koopman's theorem gives a good prediction of the ionisation energy, it is NOT because these relaxation and correlation terms are small. It is because they are of opposite sign and largely cancel. They are always quite large. Koopman's theorem is not "getting the right answer for the right reason", to quote Ernie Davidson. Localisation may be possible in only some cases, but a unitary transformation that changes the orbitals is always possible. The unitary transformation does not have to be one that generates localised orbitals. For open shell molecules the situation is different. Using restricted open shell Hartree-Fock theory, the orbital energies are not special. There is no single way to diagonalise the matrix over the Fock operator. Many different canonicalisations have been used. Some give orbital energies that satisfy Koopman's theorem; some do not. They all give the same total energy and total wave function. There is nothing special about those that do satisfy Koopman's theorem. > The second thought puzzles me since I studied Bader's theory of atoms in > molecules. Bader prefers to use only the electron density without > referring to orbitals. He shows that the electron density of ethylene > and perpendicular ethylene accounts for the pi-bond breaking upon > twisting the molecule. I am wondering, however, why the pi-bond breaks. > If orbitals are just constructs without reality, why can there be no > double bond in ethylene when the methyl groups are at 90 degree angles? > If there is an explanation without invoking the symmetry of orbitals, > which I am not aware of, I would like to learn about it. This is interesting, but I will not get into this directly. I will only comment in relation to another post and to the above topic. In MO theory, banana bonds and sigma/pi bonds are equivalent - they are related by a unitary transformation. In valence bond theory, they are different and for ethylene the banana bond model is slightly lower in energy. Are any of these 4 sets of orbitals (sigma/pi, banana LMOs, VB sigma/pi orbitals and VB banana orbitals) real? > I hope nobody feels offended if we continue the interesting discussion. I hope so too. Brian. > Ulrike > -- > Ulrike Salzner > Associate Professor > Department of Chemistry > Bilkent University > 06800 Bilkent, Ankara > Turkey -- Brian Salter-Duke (Brian Duke) b_duke#%#octa4.net.au Post: 626 Melbourne Rd, Spotswood, VIC, 3015, Australia Phone 03-93992847. http://members.iinet.net.au/~linden1/brian/ Honorary Researcher, Chem., Melbourne Univ. & Med. Chem., Monash Univ. From owner-chemistry@ccl.net Tue Dec 6 01:15:04 2005 From: "Sengen Sun sengensun]~[yahoo.com" To: CCL Subject: CCL: question on molecular orbitals in CO and NO Message-Id: <-30202-051206005258-29071-+E5jFbzA4LMyUDcLYZQmjg a server.ccl.net> X-Original-From: Sengen Sun Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=iso-8859-1 Date: Mon, 5 Dec 2005 21:52:44 -0800 (PST) MIME-Version: 1.0 Sent to CCL by: Sengen Sun [sengensun-$-yahoo.com] The most recent round of discussion is about a quote by Hoffmann. I do not agree with but I have a high respect to Hoffmann because he is the man to have an opinion. A simple answer TRUE or FALSE to the quote > from any one gains my respect no matter you explain your answer or not. Otherwise you waste your energy and are unproductive. I never ask any one to agree with me. Sorry, I am caught with the flames and cannot run! Sengen > From: Alan Shusterman > Subject: CCL: question on molecular orbitals in CO > and > NO > Date: Mon, 05 Dec 2005 19:56:49 -0800 > > -------------------------------------------------------------------------------- > Three points. > > 1. Re: Itatani et al. > > I'm sorry that I didn't keep the emails that I > exchanged with Itatani (or possibly it was another > author?). Itatani (?) admitted to me that, even > though > the article said "orbitals" had been imaged, it was > unnecessary (but more fun) to interpret the data in > this way. > > 2. Orbitals & CI > > As we all know (but are tempted to forget?), > orbital-based wave functions cannot provide exact > solutions of the Schrodinger equation unless we work > with a complete (infinite) basis set and develop a > complete (infinite) CI expansion within this basis > set. > > This means that hardly any of the determinants in > the > CI will be based on identical orbitals. Two randomly > selected determinants will only have a few orbitals > in > common, and some determinants will have no two > orbitals in common. This poses an insurmountable > problem for the members of the "orbitals are > real-orbitals are observable" camp. There is no way > to > say which determinant in a complete CI expansion > contains the "real/observable" orbitals. (If there > were, what would one say about the infinite number > of > other orbitals that appear in the other > determinants?) > > 3. Can we move this conversation forward? > > It seems to me that the last time the "are orbitals > real?" question arose, the discussion on the list > eventually moved in some interesting directions, but > only because the contributors moved beyond the stale > (but sadly neverending) debate over "are orbitals > real?" This is just my opinion, but it's too bad > that > so much energy gets expended over something as basic > and unproductive as "are orbitals real?" However, if > this is the price to pay for interesting questions, > like "how does model X (AIM, NBO, FMO, etc.) explain > phenomenon Y (twisting in ethylene, etc.)?" then > I'll > gladly pay it. But I can't help wishing that there > was > a simpler path to these scientifically productive > questions. > > (I imagine biologists would feel the same > frustration > if the only way for them to talk about mutations, > etc., was to first ask and discuss whether everyone > in > the room agreed that evolution by natural selection > was a real phenomenon.) > > -Alan > > > > > > > __________________________________________ > Yahoo! DSL ?Something to write home about. > Just $16.99/mo. or less. > dsl.yahoo.com > > __________________________________________ Yahoo! DSL – Something to write home about. Just $16.99/mo. or less. dsl.yahoo.com From owner-chemistry@ccl.net Tue Dec 6 09:32:00 2005 From: "Telkuni Tsuru telkuni*venus.dti.ne.jp" To: CCL Subject: CCL:G: TDDFT calculation in water solvent Message-Id: <-30203-051206092220-32251-fYCuBQgr8t0aQrQonCNlTg,+,server.ccl.net> X-Original-From: "Telkuni Tsuru" Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="iso-2022-jp" Date: Tue, 6 Dec 2005 23:22:05 +0900 MIME-Version: 1.0 Sent to CCL by: "Telkuni Tsuru" [telkuni|*|venus.dti.ne.jp] Hello, CCLers. I'm trying to do TDDFT calculation in water solvent using Gaussian98W_A7. I wrote following GJF of which molecular CO2 coordination was optimized by HF/STO-3G. ============ GJF ============ %Chk=TD_CO2 ** CO2 optimization by HF/STO-3G ** --Link1-- %Chk=TD_CO2 #T TD(50-50) B3PW91/6-31G(d) SCRF(IPCM) Pop=Reg Geom=Check Guess=Read TDDFT-CO2 in Water 0,1 78.4 0.001 40 20 ============ end of GJF ============ Although the first job step(optimization) was succeed, second job step(TDDFT) was failed with following error massage: -------------------------------------------------- Reaction Field using a Density IsoSurface Boundary -------------------------------------------------- Epsi= 78.4000 Cont = 0.0010 Will Allow IsoSurface To Relax Throughout Convergence set to 1.00D-06 40 Phi and 20 Theta Values Per Atom NABMO STP ISTEP RAD NUMR CUTOFF DStMX0 MoBas? 4 5.00E-02 5 1.0E-01 20 1.0E-10 1.0E+01 F Using single center to handle rho isosurface. Density number -1 is not available. Error termination via Lnk1e in C:\G98W\l117.exe. Job cpu time: 0 days 0 hours 6 minutes 17.0 seconds. File lengths (MBytes): RWF= 10 Int= 0 D2E= 0 Chk= 3 Scr= 1 ============ end of error massage ============ I guess that the problem depends on Link117, but I don't have any idea to know the reason. If you have any advice or example input, please send me (or send to this ML). All responses I'll appreciate. I'll summarize them and upload to ML. Sincerely yours, ---------------------------------------------------- Telkuni Tsuru telkuni(-)venus.dti.ne.jp Bunshi Gijyutu From owner-chemistry@ccl.net Tue Dec 6 12:51:00 2005 From: "Eric Scerri scerri : chem.ucla.edu" To: CCL Subject: CCL: question on molecular orbitals in CO and NO Message-Id: <-30204-051206124837-11924-ipYRUcFzzc1/5tu6+5bAXA++server.ccl.net> X-Original-From: Eric Scerri Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Date: Tue, 6 Dec 2005 09:47:39 -0800 Mime-Version: 1.0 (Apple Message framework v746.2) Sent to CCL by: Eric Scerri [scerri{}chem.ucla.edu] Thank you for your detailed response Alan, Can I just add that I was not intending to perpetuate the "are they real/ are they observable" discussion but trying to shift the ground to the question of 'observation' of phases of orbitals. This is an issue that has been increasingly discussed by experimentalists as far as I can see. Maybe this is not the list to be addressing experimental questions to? However if there is one positive aspect of the "are they real/ observable" discussion perhaps it is the fact that it is pitting experimentalists and theorists against each other in a new way. Experimentalists have been too quick to claim that they are observing orbitals while at the same time it may be that some theorists have been too quick to dismiss the whole issue just on principle. Neither reaction seems particularly productive. So with some trepidation let me ask again, what is involved in the alleged observation of the relative phases of atomic and molecular orbitals? Or can somebody please direct me to the relevant listserver where such questions might be discussed. eric scerri ----------------------------------------------- On Dec 5, 2005, at 8:48 PM, Alan Shusterman alan_._reed.edu wrote: > Sent to CCL by: Alan Shusterman [alan-,-reed.edu] > This is a multi-part message in MIME format. > --------------040802050402060409090209 > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > Content-Transfer-Encoding: 7bit > > Three points. > > 1. Re: Itatani et al. > > I'm sorry that I didn't keep the emails that I exchanged with Itatani > (or possibly it was another author?). Itatani (?) admitted to me that, > even though the article said "orbitals" had been imaged, it was > unnecessary (but more fun) to interpret the data in this way. > > 2. Orbitals & CI > > As we all know (but are tempted to forget?), orbital-based wave > functions cannot provide exact solutions of the Schrodinger equation > unless we work with a complete (infinite) basis set and develop a > complete (infinite) CI expansion within this basis set. > > This means that hardly any of the determinants in the CI will be based > on identical orbitals. Two randomly selected determinants will only > have > a few orbitals in common, and some determinants will have no two > orbitals in common. This poses an insurmountable problem for the > members > of the "orbitals are real-orbitals are observable" camp. There is > no way > to say which determinant in a complete CI expansion contains the > "real/observable" orbitals. (If there were, what would one say > about the > infinite number of other orbitals that appear in the other > determinants?) > > 3. Can we move this conversation forward? > > It seems to me that the last time the "are orbitals real?" question > arose, the discussion on the list eventually moved in some interesting > directions, but only because the contributors moved beyond the stale > (but sadly neverending) debate over "are orbitals real?" This is > just my > opinion, but it's too bad that so much energy gets expended over > something as basic and unproductive as "are orbitals real?" > However, if > this is the price to pay for interesting questions, like "how does > model > X (AIM, NBO, FMO, etc.) explain phenomenon Y (twisting in ethylene, > etc.)?" then I'll gladly pay it. But I can't help wishing that > there was > a simpler path to these scientifically productive questions. > > (I imagine biologists would feel the same frustration if the only way > for them to talk about mutations, etc., was to first ask and discuss > whether everyone in the room agreed that evolution by natural > selection > was a real phenomenon.) > > -Alan > > Eric Scerri scerri_+_chem.ucla.edu wrote: > >> Sent to CCL by: Eric Scerri [scerri,chem.ucla.edu] >> >> Just a point about all this, >> >> There are now claims that relative phases have been observed, as in >> the recent Itatani paper in Nature. >> >> What do listmembers think of the this? Does it constitute the >> observation of orbitals in any sense? >> >> Or would that require the observation of absolute phases? >> >> >> >> eric scerri >> >> >> >> --------------------------------------------------------------------- >> --- >> ------------------------ >> On Dec 2, 2005, at 10:43 AM, Sengen Sun sengensuna/yahoo.com wrote: >> >> >> >>> Sent to CCL by: Sengen Sun [sengensun() yahoo.com] >>> Joslyn, >>> >>> Good suggestion. Let us put it off to avoid being >>> heated up. I thought the winter and the blizard could >>> help...... >>> >>> Actually, the heat could be avoided if we just simply >>> say TRUE or FALSE to the quote by Hoffmann. >>> >>> I have been overwhelmed by some heat of agreements and >>> disagreements in a bunch of private e-mails in the >>> last 30 hours. A coule of them are too long without a >>> clear point. >>> >>> If an experimental quantity A tells something or some >>> actions about B, B then can be measured through A. In >>> the other words, can a physical reality tell anything >>> of no physical existence and no physical meaning? Is >>> not this an interesting philosophical issue? >>> >>> But we, including many Doctors of Philosophy, should >>> put off the discussion, ignore it, or discard it to >>> avoid being burnt! Let us go back to our daily things >>> that do not generate heat then. I have no problem to >>> go back to some cool science and cool philisophy. >>> >>> Thanks to every one for contributions and attention. >>> >>> >>> -:) >>> >>> Sengen >>> ------------------------------------------------ >>> >>> >>> >>> >>>> From: Joslyn Y Kravitz >>>> Subject: CCL: question on molecular orbitals in CO >>>> and NO >>>> Date: Thu, 1 Dec 2005 15:57:37 -0500 (EST) >>>> >>>> >>>> Didn't we just have this conversation in February? >>>> Not that it wasn't interesting but I seem to recall >>>> >>>> >>> that >>> >>> >>>> it got rather heated and since we've recently had a >>>> bunch of heated debates on the list maybe now is not >>>> the time to do this again. >>>> >>>> >>>> >>>> __________________________________ >>>> Start your day with Yahoo! - Make it your home page! >>>> >>>> http://www.yahoo.com/r/hs >>>> >>>> >>>> >>> >>> >>> >>> >>> __________________________________________ >>> Yahoo! DSL - Something to write home about. >>> Just $16.99/mo. or less. >>> dsl.yahoo.com >>> >>> >>> >>> -= This is automatically added to each message by the mailing >>> script =- >>> To recover the email address of the author of the message, please >>> change> >>> Search Messages: http://www.ccl.net/htdig (login: ccl, Password: >>> search)> >>> -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- >>> +-+-+ >>> >>> >>> >>> >> >> Dr. Eric Scerri >> Department of Chemistry & Biochemistry, >> Charles Young Drive, >> Los Angeles, >> CA 90095. >> >> 310 206 7443 >> fax: 310 206 2061 >> >> UCLA faculty web page: http://www.chem.ucla.edu/dept/Faculty/scerri/ >> >> Editor of Foundations of Chemistry, >> http://springerlink.metapress.com/(uw25gnu4jydrz5555tyeokjs)/app/ >> home/ >> journal.asp?referrer=parent&backto=linkingpublicationresults, >> 1:103024,1> >> >> >> >> > > -- > Alan Shusterman > Chemistry Department > Reed College > Portland, OR 97202-8199 > 503-517-7699 > http://academic.reed.edu/chemistry/alan/ > "Yield and overcome; Bend and be straight." Lao Tzu 22 > > > --------------040802050402060409090209 > Content-Type: text/html; charset=ISO-8859-1 > Content-Transfer-Encoding: 7bit > > > > > > > > Three points.
>
> 1. Re: Itatani et al.
>
> I'm sorry that I didn't keep the emails that I exchanged with Itatani > (or possibly it was another author?). Itatani (?) admitted to me that, > even though the article said "orbitals" had been imaged, it was > unnecessary (but more fun) to interpret the data in this way.
>
> 2. Orbitals & CI
>
> As we all know (but are tempted to forget?), orbital-based wave > functions cannot provide exact solutions of the Schrodinger equation > unless we work with a complete (infinite) basis set and develop a > complete (infinite) CI expansion within this basis set.
>
> This means that hardly any of the determinants in the CI will be based > on identical orbitals. Two randomly selected determinants will only > have a few orbitals in common, and some determinants will have no two > orbitals in common. This poses an insurmountable problem for the > members of the "orbitals are real-orbitals are observable" camp. There > is no way to say which determinant  in a complete CI expansion > contains > the "real/observable" orbitals. (If there were, what would one say > about the infinite number of other orbitals that appear in the other > determinants?)
>
> 3. Can we move this conversation forward?
>
> It seems to me that the last time the "are orbitals real?" question > arose, the discussion on the list eventually moved in some interesting > directions, but only because the contributors moved beyond the stale > (but sadly neverending) debate over "are orbitals real?" This is just > my opinion, but it's too bad that so much energy gets expended over > something as basic and unproductive as "are orbitals real?" > However, if > this is the price to pay for interesting questions, like "how does > model X (AIM, NBO, FMO, etc.) explain phenomenon Y (twisting in > ethylene, etc.)?" then I'll gladly pay it. But I can't help wishing > that there was a simpler path to these scientifically productive > questions.
>
> (I imagine biologists would feel the same frustration if the only way > for them to talk about mutations, etc., was to first ask and discuss > whether everyone in the room agreed that evolution by natural > selection > was a real phenomenon.)
>
> -Alan
>
> Eric Scerri scerri_+_chem.ucla.edu wrote: >
cite="mid-id%235d5-30165-051203092801-13728-9u4y63jukxpa1sb35jZX1g] > *[server.ccl.net" > type="cite"> > 
Sent to CCL by: Eric Scerri [scerri,chem.ucla.edu]
>
> Just a point about all this,
>
> There are now claims that relative phases have been observed, as in
> the recent Itatani paper in Nature.
>
> What do listmembers think of the this?  Does it constitute the
> observation of orbitals in any sense?
>
> Or would that require the observation of absolute phases?
>
>
>
> eric scerri
>
>
>
> ---------------------------------------------------------------------- 
> --
> ------------------------
> On Dec 2, 2005, at 10:43 AM, Sengen Sun sengensuna/yahoo.com wrote:
>
>
>
> 
Sent to CCL by: Sengen Sun [sengensun() yahoo.com]
> Joslyn,
>
> Good suggestion. Let us put it off to avoid being
> heated up. I thought the winter and the blizard could
> help......
>
> Actually, the heat could be avoided if we just simply
> say TRUE or FALSE to the quote by Hoffmann.
>
> I have been overwhelmed by some heat of agreements and
> disagreements in a bunch of private e-mails in the
> last 30 hours. A coule of them are too long without a
> clear point.
>
> If an experimental quantity A tells something or some
> actions about B, B then can be measured through A. In
> the other words, can a physical reality tell anything
> of no physical existence and no physical meaning? Is
> not this an interesting philosophical issue?
>
> But we, including many Doctors of Philosophy, should
> put off the discussion, ignore it, or discard it to
> avoid being burnt! Let us go back to our daily things
> that do not generate heat then. I have no problem to
> go back to some cool science and cool philisophy.
>
> Thanks to every one for contributions and attention.
>
>
> -:)
>
> Sengen
> ------------------------------------------------
>
>
>
>
> 
From: Joslyn Y Kravitz <jyudenfr###umich.edu>
> Subject: CCL: question on molecular orbitals in CO
> and NO
> Date: Thu, 1 Dec 2005 15:57:37 -0500 (EST)
>
>
> Didn't we just have this conversation in February?
> Not that it wasn't interesting but I seem to recall
>
>
> 
that
>
>
> 
it got rather heated and since we've recently had a
> bunch of heated debates on the list maybe now is not
> the time to do this again.
>
>
> 		
> __________________________________
> Start your day with Yahoo! - Make it your home page!
>
> http://www.yahoo.com/r/hs
>
>
>
> 
>
>
>
> 		
> __________________________________________
> Yahoo! DSL – Something to write home about.
> Just $16.99/mo. or less.
> dsl.yahoo.com>
> Search Messages: http://www.ccl.net/htdig  (login: ccl,  
> Password:
> search)>
> -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
> +-+-+
>
>
>
>
> 

> Dr. Eric Scerri
> Department of Chemistry & Biochemistry,
> Charles Young Drive,
> Los Angeles,
> CA 90095.
>
> 310 206 7443
> fax: 310 206 2061
>
> UCLA faculty web page:   href="http://www.chem.ucla.edu/dept/Faculty/scerri/">http:// 
> www.chem.ucla.edu/dept/Faculty/scerri/
>
> Editor of Foundations of Chemistry,
> http:// 
> springerlink.metapress.com/(uw25gnu4jydrz5555tyeokjs)/app/home/
> journal.asp?referrer=parent&backto=linkingpublicationresults, 
> 1:103024,1E-mail to subscribers: CHEMISTRY]*[ccl.net a> or use:
>       http://www.ccl.net/cgi-bin/ccl/ 
> send_ccl_message
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> 
--
> Alan Shusterman
> Chemistry Department
> Reed College
> Portland, OR 97202-8199
> 503-517-7699
> http://academic.reed.edu/chemistry/alan/
> "Yield and overcome; Bend and be straight." Lao Tzu 22
> > > > --------------040802050402060409090209-- > > > > -= This is automatically added to each message by the mailing > script =- > To recover the email address of the author of the message, please > change> > Search Messages: http://www.ccl.net/htdig (login: ccl, Password: > search)> > -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- > +-+-+ > > Dr. Eric Scerri Department of Chemistry & Biochemistry, Charles Young Drive, Los Angeles, CA 90095. 310 206 7443 fax: 310 206 2061 UCLA faculty web page: http://www.chem.ucla.edu/dept/Faculty/scerri/ Editor of Foundations of Chemistry, http://springerlink.metapress.com/(uw25gnu4jydrz5555tyeokjs)/app/home/ journal.asp?referrer=parent&backto=linkingpublicationresults,1:103024,1 From owner-chemistry@ccl.net Tue Dec 6 13:26:01 2005 From: "hu hujia hujia02*_*gmail.com" To: CCL Subject: CCL: question on molecular orbitals in CO and NO Message-Id: <-30205-051206081515-20945-lAYADWMKX57yRq13EUle9A]~[server.ccl.net> X-Original-From: hu hujia Content-Type: multipart/alternative; boundary="----=_Part_4471_20877290.1133871422119" Date: Tue, 6 Dec 2005 20:17:02 +0800 MIME-Version: 1.0 Sent to CCL by: hu hujia [hujia02 . gmail.com] ------=_Part_4471_20877290.1133871422119 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Let me add some brick: M.O. theory is at least partially right, in that they have proving PES data= , but note PES is NOT a bunch of lines, it HAS its width, that means one M.O. orbital does not just have one single energy, above or below this energy there IS some posibility, which will decrease in exponential scales, like this: . . . . . .................. ------------------ Traditional M.O.orbital .................. . . . . . This is crucial important in Conical Intersections, Funnels or Landau-Zener rules. 2005/12/6, Alan Shusterman alan_._reed.edu : > > Sent to CCL by: Alan Shusterman [alan-,-reed.edu] > This is a multi-part message in MIME format. > --------------040802050402060409090209 > Content-Type: text/plain; charset=3DISO-8859-1; format=3Dflowed > Content-Transfer-Encoding: 7bit > > Three points. > > 1. Re: Itatani et al. > > I'm sorry that I didn't keep the emails that I exchanged with Itatani > (or possibly it was another author?). Itatani (?) admitted to me that, > even though the article said "orbitals" had been imaged, it was > unnecessary (but more fun) to interpret the data in this way. > > 2. Orbitals & CI > > As we all know (but are tempted to forget?), orbital-based wave > functions cannot provide exact solutions of the Schrodinger equation > unless we work with a complete (infinite) basis set and develop a > complete (infinite) CI expansion within this basis set. > > This means that hardly any of the determinants in the CI will be based > on identical orbitals. Two randomly selected determinants will only have > a few orbitals in common, and some determinants will have no two > orbitals in common. This poses an insurmountable problem for the members > of the "orbitals are real-orbitals are observable" camp. There is no way > to say which determinant in a complete CI expansion contains the > "real/observable" orbitals. (If there were, what would one say about the > infinite number of other orbitals that appear in the other determinants?) > > 3. Can we move this conversation forward? > > It seems to me that the last time the "are orbitals real?" question > arose, the discussion on the list eventually moved in some interesting > directions, but only because the contributors moved beyond the stale > (but sadly neverending) debate over "are orbitals real?" This is just my > opinion, but it's too bad that so much energy gets expended over > something as basic and unproductive as "are orbitals real?" However, if > this is the price to pay for interesting questions, like "how does model > X (AIM, NBO, FMO, etc.) explain phenomenon Y (twisting in ethylene, > etc.)?" then I'll gladly pay it. But I can't help wishing that there was > a simpler path to these scientifically productive questions. > > (I imagine biologists would feel the same frustration if the only way > for them to talk about mutations, etc., was to first ask and discuss > whether everyone in the room agreed that evolution by natural selection > was a real phenomenon.) > > -Alan > > Eric Scerri scerri_+_chem.ucla.edu wrote: > > >Sent to CCL by: Eric Scerri [scerri,chem.ucla.edu] > > > >Just a point about all this, > > > >There are now claims that relative phases have been observed, as in > >the recent Itatani paper in Nature. > > > >What do listmembers think of the this? Does it constitute the > >observation of orbitals in any sense? > > > >Or would that require the observation of absolute phases? > > > > > > > >eric scerri > > > > > > > >------------------------------------------------------------------------ > >------------------------ > >On Dec 2, 2005, at 10:43 AM, Sengen Sun sengensuna/yahoo.com wrote: > > > > > > > >>Sent to CCL by: Sengen Sun [sengensun() yahoo.com] > >>Joslyn, > >> > >>Good suggestion. Let us put it off to avoid being > >>heated up. I thought the winter and the blizard could > >>help...... > >> > >>Actually, the heat could be avoided if we just simply > >>say TRUE or FALSE to the quote by Hoffmann. > >> > >>I have been overwhelmed by some heat of agreements and > >>disagreements in a bunch of private e-mails in the > >>last 30 hours. A coule of them are too long without a > >>clear point. > >> > >>If an experimental quantity A tells something or some > >>actions about B, B then can be measured through A. In > >>the other words, can a physical reality tell anything > >>of no physical existence and no physical meaning? Is > >>not this an interesting philosophical issue? > >> > >>But we, including many Doctors of Philosophy, should > >>put off the discussion, ignore it, or discard it to > >>avoid being burnt! Let us go back to our daily things > >>that do not generate heat then. I have no problem to > >>go back to some cool science and cool philisophy. > >> > >>Thanks to every one for contributions and attention. > >> > >> > >>-:) > >> > >>Sengen > >>------------------------------------------------ > >> > >> > >> > >> > >>>From: Joslyn Y Kravitz > >>>Subject: CCL: question on molecular orbitals in CO > >>>and NO > >>>Date: Thu, 1 Dec 2005 15:57:37 -0500 (EST) > >>> > >>> > >>>Didn't we just have this conversation in February? > >>>Not that it wasn't interesting but I seem to recall > >>> > >>> > >>that > >> > >> > >>>it got rather heated and since we've recently had a > >>>bunch of heated debates on the list maybe now is not > >>>the time to do this again. > >>> > >>> > >>> > >>>__________________________________ > >>>Start your day with Yahoo! - Make it your home page! > >>> > >>>http://www.yahoo.com/r/hs > >>> > >>> > >>> > >> > >> > >> > >> > >>__________________________________________ > >>Yahoo! DSL - Something to write home about. > >>Just $16.99/mo. or less. > >>dsl.yahoo.com > >> > >> > >> > >>-=3D This is automatically added to each message by the mailing > >>script =3D- > >>To recover the email address of the author of the message, please > >>change> > >>Search Messages: http://www.ccl.net/htdig (login: ccl, Password: > >>search)> > >>-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- > >>+-+-+ > >> > >> > >> > >> > > > >Dr. Eric Scerri > >Department of Chemistry & Biochemistry, > >Charles Young Drive, > >Los Angeles, > >CA 90095. > > > >310 206 7443 > >fax: 310 206 2061 > > > >UCLA faculty web page: http://www.chem.ucla.edu/dept/Faculty/scerri/ > > > >Editor of Foundations of Chemistry, > >http://springerlink.metapress.com/(uw25gnu4jydrz5555tyeokjs)/app/home/ > >journal.asp?referrer=3Dparent&backto=3Dlinkingpublicationresults,1:10302= 4,1> > > > > > > > > > > -- > Alan Shusterman > Chemistry Department > Reed College > Portland, OR 97202-8199 > 503-517-7699 > http://academic.reed.edu/chemistry/alan/ > "Yield and overcome; Bend and be straight." Lao Tzu 22 > > > --------------040802050402060409090209 > Content-Type: text/html; charset=3DISO-8859-1 > Content-Transfer-Encoding: 7bit > > > > > > > > Three points.
>
> 1. Re: Itatani et al.
>
> I'm sorry that I didn't keep the emails that I exchanged with Itatani > (or possibly it was another author?). Itatani (?) admitted to me that, > even though the article said "orbitals" had been imaged, it was > unnecessary (but more fun) to interpret the data in this way.
>
> 2. Orbitals & CI
>
> As we all know (but are tempted to forget?), orbital-based wave > functions cannot provide exact solutions of the Schrodinger equation > unless we work with a complete (infinite) basis set and develop a > complete (infinite) CI expansion within this basis set.
>
> This means that hardly any of the determinants in the CI will be based > on identical orbitals. Two randomly selected determinants will only > have a few orbitals in common, and some determinants will have no two > orbitals in common. This poses an insurmountable problem for the > members of the "orbitals are real-orbitals are observable" camp. There > is no way to say which determinant  in a complete CI expansion > contains > the "real/observable" orbitals. (If there were, what would one say > about the infinite number of other orbitals that appear in the other > determinants?)
>
> 3. Can we move this conversation forward?
>
> It seems to me that the last time the "are orbitals real?" question > arose, the discussion on the list eventually moved in some interesting > directions, but only because the contributors moved beyond the stale > (but sadly neverending) debate over "are orbitals real?" This is just > my opinion, but it's too bad that so much energy gets expended over > something as basic and unproductive as "are orbitals real?" However, if > this is the price to pay for interesting questions, like "how does > model X (AIM, NBO, FMO, etc.) explain phenomenon Y (twisting in > ethylene, etc.)?" then I'll gladly pay it. But I can't help wishing > that there was a simpler path to these scientifically productive > questions.
>
> (I imagine biologists would feel the same frustration if the only way > for them to talk about mutations, etc., was to first ask and discuss > whether everyone in the room agreed that evolution by natural selection > was a real phenomenon.)
>
> -Alan
>
> Eric Scerri scerri_+_chem.ucla.edu wrote: >
cite=3D"mid-id%235d5-30165-051203092801-13728-9u4y63jukxpa1sb35jZX1g]*[ > server.ccl.net" > type=3D"cite"> > 
Sent to CCL by: Eric Scerri [scerri,chem.ucla.edu]
>
> Just a point about all this,
>
> There are now claims that relative phases have been observed, as in
> the recent Itatani paper in Nature.
>
> What do listmembers think of the this?  Does it constitute the
> observation of orbitals in any sense?
>
> Or would that require the observation of absolute phases?
>
>
>
> eric scerri
>
>
>
> ------------------------------------------------------------------------
> ------------------------
> On Dec 2, 2005, at 10:43 AM, Sengen Sun sengensuna/yahoo.com wrote:
>
>
>
> 
Sent to CCL by: Sengen Sun [sengensun() yahoo.com]
> Joslyn,
>
> Good suggestion. Let us put it off to avoid being
> heated up. I thought the winter and the blizard could
> help......
>
> Actually, the heat could be avoided if we just simply
> say TRUE or FALSE to the quote by Hoffmann.
>
> I have been overwhelmed by some heat of agreements and
> disagreements in a bunch of private e-mails in the
> last 30 hours. A coule of them are too long without a
> clear point.
>
> If an experimental quantity A tells something or some
> actions about B, B then can be measured through A. In
> the other words, can a physical reality tell anything
> of no physical existence and no physical meaning? Is
> not this an interesting philosophical issue?
>
> But we, including many Doctors of Philosophy, should
> put off the discussion, ignore it, or discard it to
> avoid being burnt! Let us go back to our daily things
> that do not generate heat then. I have no problem to
> go back to some cool science and cool philisophy.
>
> Thanks to every one for contributions and attention.
>
>
> -:)
>
> Sengen
> ------------------------------------------------
>
>
>
>
> 
From: Joslyn Y Kravitz <jyudenfr###umich.edu>
> Subject: CCL: question on molecular orbitals in CO
> and NO
> Date: Thu, 1 Dec 2005 15:57:37 -0500 (EST)
>
>
> Didn't we just have this conversation in February?
> Not that it wasn't interesting but I seem to recall
>
>
> 
that
>
>
> 
it got rather heated and since we've recently had a
> bunch of heated debates on the list maybe now is not
> the time to do this again.
>
>
>
> __________________________________
> Start your day with Yahoo! - Make it your home page!
>
> 
> http://www.yahoo.com/r/hs
>
>
>
> 
>
>
>
>
> __________________________________________
> Yahoo! DSL – Something to write home about.
> Just $16.99/mo. or less.
> dsl.yahoo.com>
> Search Messages:  http://www.ccl.net/htdig">http://www.ccl.net/htdig  (login: ccl,
> Password:
> search)>
> -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
> +-+-+
>
>
>
>
> 

> Dr. Eric Scerri
> Department of Chemistry & Biochemistry,
> Charles Young Drive,
> Los Angeles,
> CA 90095.
>
> 310 206 7443
> fax: 310 206 2061
>
> UCLA faculty web page:   http://www.chem.ucla.edu/dept/Faculty/scerri/">
> http://www.chem.ucla.edu/dept/Faculty/scerri/
>
> Editor of Foundations of Chemistry,
>  http://springerlink.metapress.com/(uw25gnu4jydrz5555tyeokjs">
> http://springerlink.metapress.com/(uw25gnu4jydrz5555tyeokjs)/app/home=
/
> journal.asp?referrer=3Dparent&backto=3Dlinkingpublicationresults,1:10=
3024,1E-mail
> to subscribers:  ]*[ccl.net">CHEMISTRY]*[ccl.net or use:
>       
>
> E-mail to administrators:  href=3D"mailto:CHEMISTRY-REQUEST]*[ccl.net">CHEMISTRY-REQUEST]*[ccl.net
> or use
>        class=3D"moz-txt-link-freetext" href=3D""
>
> Before posting, check wait time at:  href=3D"http://www.ccl.net">http://www.ccl.net
>
> Job advertisements:  http://www.ccl.net/jobs">http://www.ccl.net/jobs
>
> Search Messages:  http://www.ccl.net/htdig">http://www.ccl.net/htdig  (login: ccl,
> Password: search)http://www.ccl.net/spammers.txt
>
> RTFI:  http://www.ccl.net/chemistry/aboutccl/instructions/">
> http://www.ccl.net/chemistry/aboutccl/instructions/
>
>
> 
--
> Alan Shusterman
> Chemistry Department
> Reed College
> Portland, OR 97202-8199
> 503-517-7699
>  http://academic.reed.edu/chemistry/alan/">
> http://academic.reed.edu/chemistry/alan/
> "Yield and overcome; Bend and be straight." Lao Tzu 22
> > > > --------------040802050402060409090209-- > > > > -=3D This is automatically added to each message by the mailing script = =3D-> > > > ------=_Part_4471_20877290.1133871422119 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Let me add some brick:
M.O. theory is at least partially right, in that they have proving PES data, but note PES is NOT a bunch of lines, it HAS its width, that means one M.O. orbital does not just have one single energy, above or below this energy there IS some posibility, which will decrease in exponential scales, like this:   .   .   .   .    .
         ..................
         ------------------ &n= bsp;   Traditional M.O.orbital
         ..................
         .   .  = ; .   .   .
This is crucial important in Conical Intersections, Funnels or Landau-Zener= rules.

2005/12/6, Alan Shusterman = alan_._reed.edu <owner-chemis= try=-=ccl.net >:
S= ent to CCL by: Alan Shusterman [alan-,-reed.edu= ]
This is a multi-part message in MIME format.
--------------04080205= 0402060409090209
Content-Type: text/plain; charset=3DISO-8859-1; format= =3Dflowed
Content-Transfer-Encoding: 7bit

Three points.

1.= Re: Itatani et al.

I'm sorry that I didn't keep the emails that I exchanged with Itata= ni
(or possibly it was another author?). Itatani (?) admitted to me that= ,
even though the article said "orbitals" had been imaged, it = was
unnecessary (but more fun) to interpret the data in this way.

2.= Orbitals & CI

As we all know (but are tempted to forget?), orbi= tal-based wave
functions cannot provide exact solutions of the Schroding= er equation
unless we work with a complete (infinite) basis set and develop a
co= mplete (infinite) CI expansion within this basis set.

This means tha= t hardly any of the determinants in the CI will be based
on identical or= bitals. Two randomly selected determinants will only have
a few orbitals in common, and some determinants will have no two
orb= itals in common. This poses an insurmountable problem for the members
of= the "orbitals are real-orbitals are observable" camp. There is n= o way
to say which determinant  in a complete CI expansion contains= the
"real/observable" orbitals. (If there were, what would on= e say about the
infinite number of other orbitals that appear in the oth= er determinants?)

3. Can we move this conversation forward?

It seems to me tha= t the last time the "are orbitals real?" question
arose, the d= iscussion on the list eventually moved in some interesting
directions, b= ut only because the contributors moved beyond the stale
(but sadly neverending) debate over "are orbitals real?" This= is just my
opinion, but it's too bad that so much energy gets expended = over
something as basic and unproductive as "are orbitals real?&quo= t; However, if
this is the price to pay for interesting questions, like "how does= model
X (AIM, NBO, FMO, etc.) explain phenomenon Y (twisting in ethylen= e,
etc.)?" then I'll gladly pay it. But I can't help wishing that t= here was
a simpler path to these scientifically productive questions.

(I = imagine biologists would feel the same frustration if the only way
for t= hem to talk about mutations, etc., was to first ask and discuss
whether = everyone in the room agreed that evolution by natural selection
was a real phenomenon.)

-Alan

Eric Scerri scerri_+_chem.u= cla.edu wrote:

>Sent to CCL by: Eric Scerri [scerri,chem.ucla.edu]
>
>Just a point about al= l this,
>
>There are now claims that relative phases have been observe= d, as in
>the recent Itatani paper in Nature.
>
>What do = listmembers think of the this?  Does it constitute the
>obs= ervation of orbitals in any sense?
>
>Or would that require the observation of absolute phases?>
>
>
>eric scerri
>
>
>
>--= ----------------------------------------------------------------------
>------------------------
>On Dec 2, 2005, at 10:43 AM, Sengen Sun= sengensuna/yahoo.com wrote:
>
>
>
>>Sent to CCL= by: Sengen Sun [sengensun() yahoo.com] >>Joslyn,
>>
>>Good suggestion. Let us put it off t= o avoid being
>>heated up. I thought the winter and the blizard co= uld
>>help......
>>
>>Actually, the heat could b= e avoided if we just simply
>>say TRUE or FALSE to the quote by Hoffmann.
>>
>= >I have been overwhelmed by some heat of agreements and
>>disag= reements in a bunch of private e-mails in the
>>last 30 hours. A c= oule of them are too long without a
>>clear point.
>>
>>If an experimental quantity= A tells something or some
>>actions about B, B then can be measur= ed through A. In
>>the other words, can a physical reality tell an= ything
>>of no physical existence and no physical meaning? Is
>>= ;not this an interesting philosophical issue?
>>
>>But we= , including many Doctors of Philosophy, should
>>put off the discu= ssion, ignore it, or discard it to
>>avoid being burnt! Let us go back to our daily things
>&g= t;that do not generate heat then. I have no problem to
>>go back t= o some cool science and cool philisophy.
>>
>>Thanks to e= very one for contributions and attention.
>>
>>
>>-:)
>>
>>Sengen
&g= t;>------------------------------------------------
>>
>&= gt;
>>
>>
>>>From: Joslyn Y Kravitz <jyude= nfr###umich.edu>
>>>Subject: CCL: question on molecular orbitals in CO
>&= gt;>and NO
>>>Date: Thu, 1 Dec 2005 15:57:37 -0500 (EST)
= >>>
>>>
>>>Didn't we just have this conver= sation in February?
>>>Not that it wasn't interesting but I seem to recall
>= >>
>>>
>>that
>>
>>
>>= ;>it got rather heated and since we've recently had a
>>>bun= ch of heated debates on the list maybe now is not
>>>the time to do this again.
>>>
>>><= br>>>>
>>>__________________________________
>&g= t;>Start your day with Yahoo! - Make it your home page!
>>>
>>>http://www.yahoo.com/= r/hs
>>>
>>>
>>>
>>
>= ;>
>>
>>
>>__________________________________= ________
>>Yahoo! DSL - Something to write home about.
>>Just $16= .99/mo. or less.
>>dsl.yahoo.com<= /a>
>>
>>
>>
>>-=3D This is automatical= ly added to each message by the mailing
>>script =3D-
>>To recover the email address of the auth= or of the message, please
>>change>
>>Search Messages:= http://www.ccl.net/htdig &nb= sp;(login: ccl, Password:
>>search)>
>>-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+= -+-+-+-+-+-+-+-+-+-+-+-+-+-
>>+-+-+
>>
>>
>= ;>
>>
>
>Dr. Eric Scerri
>Department of Chemi= stry & Biochemistry,
>Charles Young Drive,
>Los Angeles,
>CA 90095.
>>310 206 7443
>fax: 310 206 2061
>
>UCLA faculty web= page:  http://www.chem.ucla.edu/dept/Faculty/scerri/
>
>Editor of Foundations of Chemistry,
>http= ://springerlink.metapress.com/(uw25gnu4jydrz5555tyeokjs)/app/home/
>journal.asp?referrer=3Dparent&backto=3Dlinkingpublicationresults,1:= 103024,1>
>
>
>
>

--
Alan ShustermanChemistry Department
Reed College
Portland, OR 97202-8199
503-51= 7-7699
http://academic.re= ed.edu/chemistry/alan/
"Yield and overcome; Bend and be straigh= t." Lao Tzu 22


--------------040802050402060409090209
Content-Type: text/html; charset=3DISO-8859-1
Content-Transfer-Encoding:= 7bit

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitio= nal//EN">
<html>
<head>
  <meta c= ontent=3D"text/html;charset=3DISO-8859-1" http-equiv=3D"Cont= ent-Type">
</head>
<body bgcolor=3D"#ffffff" text=3D"#0= 00000">
Three points.<br>
<br>
1. Re: Itatani = et al.<br>
<br>
I'm sorry that I didn't keep the emails t= hat I exchanged with Itatani
(or possibly it was another author?). Itatani (?) admitted to me that,<= br>even though the article said "orbitals" had been imaged, it wa= s
unnecessary (but more fun) to interpret the data in this way.<br>= ;
<br>
2. Orbitals &amp; CI<br>
<br>
As we= all know (but are tempted to forget?), orbital-based wave
functions can= not provide exact solutions of the Schrodinger equation
unless we work w= ith a complete (infinite) basis set and develop a
complete (infinite) CI expansion within this basis set.<br>
&l= t;br>
This means that hardly any of the determinants in the CI will b= e based
on identical orbitals. Two randomly selected determinants will o= nly
have a few orbitals in common, and some determinants will have no twoorbitals in common. This poses an insurmountable problem for the
membe= rs of the "orbitals are real-orbitals are observable" camp. There
is no way to say which determinant&nbsp; in a complete CI expansion= contains
the "real/observable" orbitals. (If there were, what= would one say
about the infinite number of other orbitals that appear i= n the other
determinants?)<br>
<br>
3. Can we move this conversat= ion forward?<br>
<br>
It seems to me that the last time t= he "are orbitals real?" question
arose, the discussion on the = list eventually moved in some interesting
directions, but only because the contributors moved beyond the stale(but sadly neverending) debate over "are orbitals real?" This is= just
my opinion, but it's too bad that so much energy gets expended ove= r
something as basic and unproductive as "are orbitals real?" H= owever, if
this is the price to pay for interesting questions, like &quo= t;how does
model X (AIM, NBO, FMO, etc.) explain phenomenon Y (twisting = in
ethylene, etc.)?" then I'll gladly pay it. But I can't help wishin= g
that there was a simpler path to these scientifically productive
qu= estions.<br>
<br>
(I imagine biologists would feel the sa= me frustration if the only way
for them to talk about mutations, etc., was to first ask and discusswhether everyone in the room agreed that evolution by natural selectionwas a real phenomenon.)<br>
<br>
-Alan<br>
<br>
Eric Scerri scerri_+_chem.ucla.edu wrote:
<blockquote cite=3D"mid-id%235d5-30165-051203092801-13728-9u4y63jukxpa1sb35jZX1= g]*[server.ccl.net"
type=3D&= quot;cite">
  <pre wrap=3D"">Sent to CCL by: Eric Scerri = [scerri,chem.ucla.edu]

Just a p= oint about all this,

There are now claims that relative phases have = been observed, as in
the recent Itatani paper in Nature.

What do listmembers think of= the this?  Does it constitute the
observation of orbitals in = any sense?

Or would that require the observation of absolute phases?=



eric scerri



----------------------------------------= --------------------------------
------------------------
On Dec 2, 2= 005, at 10:43 AM, Sengen Sun sengensuna/yahoo.com wrote:

  = ;</pre>
  <blockquote type=3D"cite">
  &= nbsp; <pre wrap=3D"">Sent to CCL by: Sengen Sun [senge= nsun() yahoo.com]
Joslyn,

Good s= uggestion. Let us put it off to avoid being
heated up. I thought the winter and the blizard could
help......
=
Actually, the heat could be avoided if we just simply
say TRUE or FA= LSE to the quote by Hoffmann.

I have been overwhelmed by some heat o= f agreements and
disagreements in a bunch of private e-mails in the
last 30 hours. A = coule of them are too long without a
clear point.

If an experimen= tal quantity A tells something or some
actions about B, B then can be me= asured through A. In
the other words, can a physical reality tell anything
of no physical= existence and no physical meaning? Is
not this an interesting philosoph= ical issue?

But we, including many Doctors of Philosophy, should
put off the discussion, ignore it, or discard it to
avoid being burn= t! Let us go back to our daily things
that do not generate heat then. I = have no problem to
go back to some cool science and cool philisophy.

Thanks to every one for contributions and attention.


-:)=

Sengen
------------------------------------------------

<= br>    </pre>
    <bloc= kquote type=3D"cite">
      <pre wrap=3D"">From: Jo= slyn Y Kravitz &lt;jyudenfr###umich.edu&gt;
Subject: CCL: questi= on on molecular orbitals in CO
and NO
Date: Thu, 1 Dec 2005 15:57:37 = -0500 (EST)


Didn't we just have this conversation in February?
Not that it wasn't interesting but I seem to recall
  &nbs= p;   </pre>
    </blockquote= >
    <pre wrap=3D"">that
&nbs= p;   </pre>
    <blockquote = type=3D"cite">
      <pre = wrap=3D"">it got rather heated and since we've recently had a
bunch of heated debates on the list maybe now is not
the time to do = this again.



__________________________________
Start your= day with Yahoo! - Make it your home page!

<a class=3D"moz-t= xt-link-freetext" href=3D" http://www.yahoo.com/r/hs"= >http://www.yahoo.com/r/hs= </a>

      </pre>
 = ;   </blockquote>
    <pre w= rap=3D"">




__________________________________________
Yahoo! DS= L &#8211; Something to write home about.
Just $16.99/mo. or less.dsl.yahoo.com&gt;
Search Messages: <a class=3D"moz-txt-link-freetext" href=3D"http://www.ccl.net/= htdig">http://www.ccl.net/= htdig</a>  (login: ccl, Password:
search)&gt;
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+= -+-+-+-+-+-+-+-+-+-+-+-+-+-+-
+-+-+


    &= lt;/pre>
  </blockquote>
  <pre wrap= =3D""><!---->
Dr. Eric Scerri
Department of Chemistry &amp; Biochemistry,
Charles Young Drive,=
Los Angeles,
CA 90095.

310 206 7443
fax: 310 206 2061
<= br>UCLA faculty web page:  <a class=3D"moz-txt-link-freet= ext" href=3D" http://www.= chem.ucla.edu/dept/Faculty/scerri/">http://www.chem.ucla.edu/dept/Faculty/scerri= / </a>

Editor of Foundations of Chemistry,
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------=_Part_4471_20877290.1133871422119-- From owner-chemistry@ccl.net Tue Dec 6 14:01:01 2005 From: "Mark Thompson mark=arguslab.com" To: CCL Subject: CCL:G: opensource "chem3D" Message-Id: <-30206-051206110942-9946-MtpLkQSk73zumCxN/tG2zw_._server.ccl.net> X-Original-From: Mark Thompson Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1; format=flowed Date: Tue, 06 Dec 2005 06:46:07 -0800 MIME-Version: 1.0 Sent to CCL by: Mark Thompson [mark|a|arguslab.com] Hi Gilles, ArgusLab 4.0.1 http://www.arguslab.com is a freely distributed Windows molecular modeling package. ArgusLab includes 3D molecule builder, visualizer, QM methods (ZINDO, PM3, AM1, MNDO), MM methods (UFF), energies, spectra, geometry optimizations, drug docking, Gaussian interface, etc..... Cheers, Mark Thompson Seattle, WA. Gilles Frapper gilles.frapper%x%univ-poitiers.fr wrote: >Sent to CCL by: Gilles Frapper [gilles.frapper+*+univ-poitiers.fr] >Hello, > >Do you know a free (opensource ?) software like "Chem3D" ( "easy build" >3D molecules + semi-empirical methods - i.e. AM1/PM3/MNDO) ? >I need it for teaching (in french ;-)) > >Best regards. > >Gilles > > > -- ---------------------------- Mark Thompson mark,arguslab.com http://www.arguslab.com ---------------------------- From owner-chemistry@ccl.net Tue Dec 6 16:22:00 2005 From: "D. Afanasyev dafanasiev%a%ukr.net" To: CCL Subject: CCL: question on molecular orbitals in CO and NO Message-Id: <-30207-051206155343-6966-OoIpRCYDyQjqxEv0hjNetg .. server.ccl.net> X-Original-From: "D. Afanasyev" Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=windows-1251 Date: Tue, 06 Dec 2005 22:13:41 +0200 Mime-Version: 1.0 Sent to CCL by: "D. Afanasyev" [dafanasiev _ ukr.net] -----Original Message----- ... > The second thought puzzles me since I studied Bader's theory of atoms in > molecules. Bader prefers to use only the electron density without > referring to orbitals. He shows that the electron density of ethylene > and perpendicular ethylene accounts for the pi-bond breaking upon > twisting the molecule. I am wondering, however, why the pi-bond breaks. > If orbitals are just constructs without reality, why can there be no > double bond in ethylene when the methyl groups are at 90 degree angles? > If there is an explanation without invoking the symmetry of orbitals, > which I am not aware of, I would like to learn about it. > I hope nobody feels offended if we continue the interesting discussion. In my opinion it is not very correct to talk about "pi-", "sigma-" or "delta-bond" in molecules in spite of the quantum chemical topology (QT-AIM) at all. Yes, electron density distribution changes on going from planar to perpendicular ethylene but it doesn't account for the "pi-bond" breaking because of lack of concept "pi-bond" in the QT-AIM. One may consider only some changes in one-electron orbitals, which the total density of ethylene molecule is built from (or in the total density itself). There NO "double-bond" in ethylene molecule either in planar or in perpendicular conformation. Where do you see "double-bond" in ethylene when you consider MOs or when you see molecular graph of this molecule? The main problem is that classical chemistry concepts are frequently inserted in quantum mechanics instead of their explanation on the basis of quantum mechanics as the concept of what we call "bond" is. For ethylene molecule it is energetically favourable to be planar and it's the only reason for its planarity! Dmitriy -- Dmitriy Afanasyev Ukrainian State Chemical Technology University, 49005 Dnepropetrovsk, Ukraine > Ulrike > -- > Ulrike Salzner > Associate Professor > Department of Chemistry > Bilkent University > 06800 Bilkent, Ankara > Turkey > From owner-chemistry@ccl.net Tue Dec 6 21:00:01 2005 From: "Mark Zottola mzottola*gmail.com" To: CCL Subject: CCL: question on molecular orbitals in CO and NO Message-Id: <-30208-051206204619-27932-z9GOtyN/8wSI7Bj5em5zEQ^_^server.ccl.net> X-Original-From: Mark Zottola Content-Type: multipart/alternative; boundary="----=_Part_690_28586346.1133916412318" Date: Tue, 6 Dec 2005 19:46:52 -0500 MIME-Version: 1.0 Sent to CCL by: Mark Zottola [mzottola%gmail.com] ------=_Part_690_28586346.1133916412318 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Several thoughts on the electron density topology vs MO discussion: Electron density is, beyond any argument, a physical observable. Using topology to further analyze that density and the tools of AIM are the next generation of concepts in computational chemistry. Molecular orbitals are a mathematical construct. Clearly one does not "need" orbitals to do quantum chemistry. As was noted earlier in this discussion, this is the genesis of DFT. Are MO's a physical observable? I tend to think no. Electron density defines everything in the molecule. However, our understanding of electron density need to improve. As an example, DFT still is hard pressed to handl= e hydrogen bonding and van derwaals complexes in a totally satisfactory manner. MO theory does provide a common vocabulary for understanding the and describing electron density. Our ability to understand electron density is in its infancy. We need common ideas to express our conclusions about the electron density in a molecule. So, for now, tools like NBO analysis provide a powerful insight into molecules. But these tools and the relianc= e on MO theory will eventually diminish. Eventually MO theory will become a historical fact much as now the Bohr model of the atom holds a place in our scientific history. Please feel free to flame me personally and allow the list to stay flame free! :) Mark Zottola On 12/6/05, hu hujia hujia02*_*gmail.com wrote: > > Sent to CCL by: hu hujia [hujia02 . gmail.com] > ------=3D_Part_4471_20877290.1133871422119 > Content-Type: text/plain; charset=3DISO-8859-1 > Content-Transfer-Encoding: quoted-printable > Content-Disposition: inline > > Let me add some brick: > M.O. theory is at least partially right, in that they have proving PES > data=3D > , > but note PES is NOT a bunch of lines, it HAS its width, that means one M.= O > . > orbital does not just have one single energy, above or below this energy > there IS some posibility, which will decrease in exponential scales, like > this: . . . . . > .................. > ------------------ Traditional M.O.orbital > .................. > . . . . . > This is crucial important in Conical Intersections, Funnels or > Landau-Zener > rules. > > 2005/12/6, Alan Shusterman alan_._reed.edu : > > > > ------=_Part_690_28586346.1133916412318 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
Several thoughts on the electron density topology vs MO discussion:
 
Electron density is, beyond any argument, a physical observable. = Using topology to further analyze that density and the tools of AIM are th= e next generation of concepts in computational chemistry. 
 
Molecular orbitals are a mathematical construct.  Clearly one doe= s not "need" orbitals to do quantum chemistry.  As was noted= earlier in this discussion, this is the genesis of DFT.
 
Are MO's a physical observable?  I tend to think no.  Electr= on density defines everything in the molecule.  However, our understan= ding of electron density need to improve.  As an example, DFT still is= hard pressed to handle hydrogen bonding and van derwaals complexes in= a totally satisfactory manner. 
 
MO theory does provide a common vocabulary for understanding the = and describing electron density.  Our ability to understand electron d= ensity is in its infancy.  We need common ideas to express our conclus= ions about the electron density in a molecule.  So, for now, tools lik= e NBO analysis provide a powerful insight into molecules.  But these t= ools and the reliance on MO theory will eventually diminish.  Eve= ntually MO theory will become a historical fact much as now the Bohr model = of the atom holds a place in our scientific history.=20
 
 
Please feel free to flame me personally and allow the list to stay fla= me free! :)
 
 
Mark Zottola
 
On 12/6/05, = hu hujia hujia02*_*gmail.com <owner-chemistry+*+ccl.net> wrote= :
Sent to CCL by: hu hujia [hujia0= 2 . gmail.com]
------=3D_Part_4471_2087= 7290.1133871422119
Content-Type: text/plain; charset=3DISO-8859-1
Content-Transfer-Enco= ding: quoted-printable
Content-Disposition: inline

Let me add som= e brick:
M.O. theory is at least partially right, in that they have prov= ing PES data=3D
,
but note PES is NOT a bunch of lines, it HAS its width, that means= one M.O.
orbital does not just have one single energy, above or below t= his energy
there IS some posibility, which will decrease in exponential = scales, like
this:   .   .   .   . &nbs= p;  .
        ........= ..........
        -------------= -----     Traditional M.O.orbital
   =      ..................
    = ;    .   .   .   . &= nbsp; .
This is crucial important in Conical Intersections, Funnels or L= andau-Zener
rules.

2005/12/6, Alan Shusterman alan_._reed.edu <owner-chem= istry(-)ccl.net>:
>
>
 

 
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