From owner-chemistry@ccl.net Wed Sep 8 00:08:00 2010 From: "neeraj m neerajmisra..hotmail.com" To: CCL Subject: CCL: DFT maths Message-Id: <-42712-100908000639-6400-6gpIHVizq3OVeiXPdN9D2Q---server.ccl.net> X-Original-From: "neeraj m" Date: Wed, 8 Sep 2010 00:06:38 -0400 Sent to CCL by: "neeraj m" [neerajmisra]_[hotmail.com] I shall very appreciate if any of you all could suggest me the real stuff(mathematics) of Density functional theory.Where can i get the complete.... From owner-chemistry@ccl.net Wed Sep 8 02:39:00 2010 From: "Marcel Swart marcel.swart::icrea.es" To: CCL Subject: CCL: DFT maths Message-Id: <-42713-100908023503-6266-NDaxASCS/q4W9rW4NM6U1Q|,|server.ccl.net> X-Original-From: Marcel Swart Content-Type: multipart/alternative; boundary=Apple-Mail-3-677810201 Date: Wed, 8 Sep 2010 08:34:48 +0200 Mime-Version: 1.0 (Apple Message framework v1081) Sent to CCL by: Marcel Swart [marcel.swart(_)icrea.es] --Apple-Mail-3-677810201 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=iso-8859-1 Please have a look at the CCL archives. There are several good books on density functional theory, the classics are: Parr, Yang, "Density functional theory of atoms and molecules", Oxford = Univ. Press, 1989 Dreizler, Gross, "Density Functional Theory", Plenum Press, 1995 Koch, Holthausen, "A Chemist's Guide to Density Functional Theory", = Wiley-VCH, 2000 On Sep 8, 2010, at 6:06 AM, neeraj m neerajmisra..hotmail.com wrote: >=20 > Sent to CCL by: "neeraj m" [neerajmisra]_[hotmail.com] > I shall very appreciate if any of you all could suggest me the real = stuff(mathematics) of Density functional theory.Where can i get the = complete.... >=20 > -=3D This is automatically added to each message by the mailing script = =3D- >=20>=20=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D dr. Marcel Swart ICREA Research Professor at Institut de Qu=EDmica Computacional Universitat de Girona Parc Cient=EDfic i Tecnol=F2gic Edifici Jaume Casademont (despatx A-27) Pic de Peguera 15 17003 Girona Catalunya (Spain) tel +34-972-183240 fax +34-972-183241 e-mail marcel.swart..icrea.es marcel.swart..udg.edu web http://www.marcelswart.eu =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --Apple-Mail-3-677810201 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=iso-8859-1

Dreizler, = Gross, "Density Functional Theory", Plenum Press, 1995

Koch, = Holthausen, "A Chemist's Guide to Density Functional Theory", Wiley-VCH, = 2000

On Sep 8, 2010, at 6:06 AM, = neeraj m neerajmisra..hotmail.com wrote:

Sent to CCL by: "neeraj m" = [neerajmisra]_[hotmail.com]
I shall very appreciate if any of you all = could suggest me the real stuff(mathematics) of Density functional = theory.Where can i get the complete....

-=3D This is = automatically added to each message by the mailing script = =3D-

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= --Apple-Mail-3-677810201-- From owner-chemistry@ccl.net Wed Sep 8 04:56:00 2010 From: "William Flak williamflak|,|yahoo.com" To: CCL Subject: CCL:G: Gsolv - pKa - Frequency Message-Id: <-42714-100907165912-12193-Nf7/pSDarmhUDSuEnDy/OQ_-_server.ccl.net> X-Original-From: William Flak Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=iso-8859-1 Date: Tue, 7 Sep 2010 13:59:01 -0700 (PDT) MIME-Version: 1.0 Sent to CCL by: William Flak [williamflak=-=yahoo.com] Dear All Thanks so much for your reply. I was studying each word in your replies, it was really helpful. I read more on this topic in physical chemistry textbooks. I still have some questions, and sorry if I am going to take more from your time. * Implicit solvation models account for entropy term. But entropy is not accounted in gas calculation (sure). But how Gaussian calculates delta G(solv) using SCFVAC keyword. As I know, this keyword does SCF in gas phase in addition to that one in solvent. I am a little bit confused, sorry, it means: delta G(solv) = Gsolution - Ggas (original equation) delta G(solv) = Epcm - Egas (from Gaussian website) I mean, in Gaussian, entroy is accounted ONLY in PCM but not in gas phase. It is wrong, am I right? or Gaussian does computes entropy in gas phase as well (I can't see it in the output). * As well, if I calculated Epcm and Egas and used delta G(solv) = Epcm - Egas equation, I would get different answer from delta G(solv) calculated using SCFVAC keyword. what is the source of this difference, am I missing something? Thanks in advance W. Flak --- On Mon, 9/6/10, Michael K. Gilson mgilson-#-ucsd.edu wrote: > From: Michael K. Gilson mgilson-#-ucsd.edu > Subject: CCL:G: Gsolv - pKa - Frequency > To: "Flak, William " > Date: Monday, September 6, 2010, 2:53 PM > > Sent to CCL by: "Michael K. Gilson" [mgilson_-_ucsd.edu] > I agree with Andreas that, if an implicit solvent > model already > implicitly accounts for changes in vibrational entropy on > solvation, one > needs to be careful about double-counting this > contribution. just for > completeness, I'd mention that, when the solute is really > flexible, as > for a peptide, one would still want to think about possible > changes in > entropy due to shifts in conformational distributions due > to solvation. > > Regards, > Mike > > On 9/6/2010 12:07 AM, Andreas Klamt klamt**cosmologic.de > wrote: > > Sent to CCL by: Andreas Klamt [klamt,+,cosmologic.de] > > Hi all together, > > > > I think that Chris is quite right in most of his > arguments, and > > definitely Mike is right as well in saying that the > partial molar > > entropy is thermodynamically well defined and that it > can be > > considerably different in solution compared to the > ideal gas. > > > > But this difference is to first order already > implicitly parameterized > > into every continuum solvation model that is > parameterized versus exp. > > dG_solv. data. Since these data do include the entropy > change, the > > latter is also implicitly included into the > parameterized solvation > > models, not based on a frequency change, but via > surface proportional > > corrections. > > > > If you try to add the same via frequency based > corrections (which are > > not well defined, as I mentioned earlier and as Chris > mentioned in > > detail), you can only make things worse! > > > > In a solvation model which takes into account > temperature dependence, as > > in COSMO-RS, you can quantify the included partial > molar entropy of > > solvation based on the temperature derivative of > dG_solv. > > > > If you would like to develop a solvation model which > is open for the > > explicit addition of solvation entropy, you would have > to do that based > > on the the enthalpy (heat) of solvation, but there are > much less exp. > > data available for dH-solv than for dG_solv, and few > people are > > interested in dH_solv. The only situation for which > lots of well measure > > dG_solv ad dH_solv data are available, is > self-solvation, which is > > nothing else than free energy of vaporization (i.e. > ln(vapor pressure) > > and heat of vaporization). It should be noted that > COSMO-RS describes > > dG_vap and dH_vap consistently as self-solvation. > > > > Regarding your pKa problem (as for any reaction > calculation) this means: > > - Do the best gas phase calculation as you can afford, > incl. gas-phase > > entropy change, and then add the solvation free > energies of educts and > > products (with the right sign). > > - Or use a parameterized pKa model directly based on > the solution phase > > energy difference of protonated and deprotonated > species. > > > > Hope this helps. > > > > Andreas > > > > > > > > > > > > Am 05.09.2010 14:57, schrieb W Flak williamflak- > -yahoo.com: > >> Sent to CCL by: "W Flak" > [williamflak]![yahoo.com] > >> Dear CCL > >> I got some questions about pKa calculation hoping > to get a help here. > >> * First of all, on G03 help page, it says > Gsolvation=EPCMEgas, but if I > >> compared delta Gsolv obtained by SCFVAC with those > obtained by carrying out two > >> separate jobs, I'd get difference. Why? > >> Example: > >> by SCFVAC > >> DeltaG (solv) (kcal/mol) = -10.26 > >> By two separated jobs: > >> deta Gsolv = Epcm - Egas = -15.49 > >> > >> * Is the entropy of a molecule in gas phase > different from that in a solution? > >> if yes, please direct me to the undergraduate book > I should read > >> > >> * I read many posts on pKa calculation and found > some people (as Andreas > >> Klamt,2006) recommended not to include frequency > in pKa calculation, and the > >> others include it. What do you recommend? > >> > >> * In G.A.A. Saracino et al. / Chemical Physics > Letters 373 (2003) 411415 > >> Gibbs energies have been estimated by single point > HF/6-31+G(d,p) calculations > >> at geometries optimised in aqueous solution at the > PBE0/6-31+G(d,p) level. How > >> they calculated frequency at level differs from > the optimization level? > >> > >> Any kind of help would be appreciated > >> W. Flak> > >> > >> > > > > > -- > Michael K. Gilson, M.D., Ph.D. > Professor > Skaggs School of Pharm. and Pharm. Sci. > University of California San Diego > 9500 Gilman Drive, MC 0736 > La Jolla, California, 92093-0736 > Office: 858-822-0622 > http://pharmacy.ucsd.edu/faculty/Gilson.shtml > > > > -= This is automatically added to each message by the > mailing script =- > To recover the email address of the author of the message, > please change > the strange characters on the top line to the ]~[ sign. You > can also> > E-mail to subscribers: CHEMISTRY]~[ccl.net > or use: > > > E-mail to administrators: CHEMISTRY-REQUEST]~[ccl.net > or use > > > > > > From owner-chemistry@ccl.net Wed Sep 8 08:27:00 2010 From: "david.anick*|*rcn.com" To: CCL Subject: CCL: 6 degree of freedom for linear molecule ?????? Message-Id: <-42715-100907021535-12361-NUhZQ6ttpDQC1FhrZ1KKkA,,server.ccl.net> X-Original-From: Content-Type: multipart/alternative; boundary="-----f35fb9952ca352b9b4822b40f81341e7" Date: Mon, 6 Sep 2010 19:42:32 -0400 (EDT) MIME-Version: 1.0 Sent to CCL by: [david.anick .. rcn.com] -------f35fb9952ca352b9b4822b40f81341e7 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit -------f35fb9952ca352b9b4822b40f81341e7 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit Dear ABHISHEK SHAHI

Looking at your negative frequencies, I see two that are nearly identical (-378.71 and -378.71) and another pair that are nearly identical (-215.19 and -215.19). This is a priori extremely unlikely UNLESS your molecule possesses 4-fold or greater symmetry. You say it is linear, so obviously it has a lot of symmetry.

You ran the optimization using the 'nosymm' keyword, but that does NOT guarantee that optimization won't get stuck in a symmetrical saddle point. Gradients can be so small near such a saddle that optimization might not find the eigenvector that actually points downhill.

What has happened is this: the true minimum for your molecule is NOT linear, but optimization is stuck in a linear geometry because you started with a linear geometry.

To solve the problem, perturb the molecule by in the direction of the eigenvector associated with one of the 'negative' modes. How much to perturb? -- I can't say exactly, but make the angle(s) 165 degrees or less, rather than 180 degrees. And if there are four or more atoms, make it non-planar too, with torsional angles between 15 and 165 degrees. Then restart optimization from this emphatically non-symmetric geometry and see what happens.

Peace,
David Anick PhD MD

---- Original message ----

Date: Mon, 06 Sep 2010 08:33:21 +0200
From: "Dr.Wolfgang Quapp quapp]~[rz.uni-leipzig.de" <owner-chemistry]=[ccl.net>
Subject: CCL: 6 degree of freedom for linear molecule ??????
To: "Anick, David " <david.anick]=[rcn.com>
>
>Sent to CCL by: "Dr.Wolfgang Quapp" [quapp{}rz.uni-leipzig.de]
>Zitat von "ABHISHEK SHAHI shahi.abhishek1984!A!gmail.com"
><owner-chemistry=-=ccl.net>:
>> Dear All
>> Here optimization give a linear geometry but on frequency calculation,
>> Job gives 6(translational+rotational) frequencies and they are negative
>> enough to make any sense.My route section is "# MP2=full/aug-cc-PVTZ
>> opt=(verytight,maxcycle=100) nosymm freq=noraman
>> scf=(xqc,vshift=150,tight)".And same problem is faced by me several other
>> complexes.Please help me in this problem.your suggestions are valuable for
>> me.
>>
>> Full mass-weighted force constant matrix:
>> Low frequencies -378.7133 -378.7122 -215.1945 -215.1944 0.0043 0.0046
>> Low frequencies 0.0060 714.7626 2094.2659
>> Molecule is linear but NTrRo=6.
>> Error termination via Lnk1e in /home/pkg/lic/g09/em64t/g09/l716.exe at Fri
>> Sep 3 19:32:28 2010.
>> Job cpu time: 0 days 3 hours 7 minutes 24.7 seconds.
>>
>
>Dear ABHISHEK SHAHI,
>
>first of all, there are 7 interesting frequencies.
>Three zeros for translation are o.k.
>My be that the 2 lowest are from a saddle of index 2?
>But opt searches for a minimum?
>
>Dr.Wolfgang Quapp
>
>
>----------------------------------------------------------------
>This message was sent using IMP, the Internet Messaging Program.
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-------f35fb9952ca352b9b4822b40f81341e7-- From owner-chemistry@ccl.net Wed Sep 8 09:02:00 2010 From: "Dr Ponnadurai Ramasami ramchemi+/-intnet.mu" To: CCL Subject: CCL: ECSOC 2011 Message-Id: <-42716-100908062608-11864-KCVdPvWNKxrzHwq8SOACIw a server.ccl.net> X-Original-From: "Dr Ponnadurai Ramasami" Content-Type: multipart/alternative; boundary="----=_NextPart_000_0080_01CB4F61.BDF56870" Date: Wed, 8 Sep 2010 14:25:52 +0400 MIME-Version: 1.0 Sent to CCL by: "Dr Ponnadurai Ramasami" [ramchemi-*-intnet.mu] This is a multi-part message in MIME format. ------=_NextPart_000_0080_01CB4F61.BDF56870 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Dear All Greetings Kindly be informed about computational chemistry in ECSOC 2010. http://www.usc.es/congresos/ecsoc/14/index.htm Regards Ramasami ------=_NextPart_000_0080_01CB4F61.BDF56870 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Dear All

Greetings

Kindly be informed about computational = chemistry in=20 ECSOC 2010.

http://www.usc.es= /congresos/ecsoc/14/index.htm

Regards

Ramasami

------=_NextPart_000_0080_01CB4F61.BDF56870-- From owner-chemistry@ccl.net Wed Sep 8 20:16:01 2010 From: "Haibin Scopus lihb734\a/yahoo.com" To: CCL Subject: CCL:G: Transition dipole moment Gaussian03 Message-Id: <-42717-100907012732-24469-djmwCRIMSd5pTKUG1kYUhg[*]server.ccl.net> X-Original-From: Haibin Scopus Content-Type: multipart/alternative; boundary="0-357487427-1283817643=:28626" Date: Mon, 6 Sep 2010 17:00:43 -0700 (PDT) MIME-Version: 1.0 Sent to CCL by: Haibin Scopus [lihb734(0)yahoo.com] --0-357487427-1283817643=:28626 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Dear Sir,=20 =A0=A0 You can obtain this quality from a TDDFT or CIS calculation: =A0# B3LYP/6-31G* TD(direct,singlet,nstates=3D30) test =A0 Haibin Li Institute of Functional Material Chemistry, Faculty of Chemistry Northeast Normal University=20 changchun, Jilin, 130024 PR CHINA E-mail: lihb734()nenu.edu.cn; lihb734()yahoo.com http://www.nenu.edu.cn --- On Mon, 9/6/10, Jon Mikel Azpiroz jmkimteo|hotmail.com wrote: > From: Jon Mikel Azpiroz jmkimteo|hotmail.com Subject: CCL:G: Transition dipole moment Gaussian03 To: "Li, Hai-Bin " Date: Monday, September 6, 2010, 10:06 AM Sent to CCL by: "Jon Mikel=A0 Azpiroz" [jmkimteo*hotmail.com] Dear CCL, I would like to calculate transition dipole moments between pair of molecul= ar orbitals , where 'phi_k' and 'phi_l' are the molecular o= rbitals and 'mu' is the dipole moment operator. Does anyone know how can I = get this quantities in Gaussian 03? Thank you in advance for your attention. Jon Mikel Azpiroz University of the Basque Country -=3D This is automatically added to each message by the mailing script =3D-=A0 =A0 =A0=A0 =A0 =A0Subscribe/Unsubscribe:=20 =A0 =A0 =A0Job: http://www.ccl.net/jobs=20=A0 =A0 =A0=0A=0A=0A --0-357487427-1283817643=:28626 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable

Dear Sir,

You can obtain this quality from a TDDFT or CIS calculati= on:

# B3LYP/6-31G* TD(direct,singlet,nstates=3D30) test

Haibin Li

Institute of Functional Material Chemistry, Faculty of Chemistry
Northeast Normal University
changchun, Jilin, 130024 PR = CHINA

E-mail: lihb734()nenu.edu.cn; lihb734()yahoo.com
http://www.n= enu.edu.cn

--- On Mon, 9/6/10, Jon Mikel Azpiroz jmkimteo|h= otmail.com <owner-chemistry()ccl.net> wrote:

From: Jon Mikel Azpiroz jmkimteo|hotmail.com <= owner-chemistry()ccl.net>
Subject: CCL:G: Transition dipole moment Gau= ssian03
To: "Li, Hai-Bin " <lihb734()yahoo.com>
Date: Mo= nday, September 6, 2010, 10:06 AM

Sent to CCL by: "Jon Mikel Azpiroz" [jmkim= teo*hotmail.com]
Dear CCL,

I would like to calculate transition d= ipole moments between pair of molecular orbitals <phi_k|mu|phi_l>, wh= ere 'phi_k' and 'phi_l' are the molecular orbitals and 'mu' is the dipole m= oment operator. Does anyone know how can I get this quantities in Gaussian = 03?

Thank you in advance for your attention.

Jon Mikel Azpiro= z
University of the Basque Country

-=3D This is automatic= ally added to each message by the mailing script =3D-
To recover the ema= il address of the author of the message, please change
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=0A=0A --0-357487427-1283817643=:28626-- From owner-chemistry@ccl.net Wed Sep 8 22:45:00 2010 From: "Andreas Klamt klamt[*]cosmologic.de" To: CCL Subject: CCL:G: Gsolv - pKa - Frequency Message-Id: <-42718-100908223404-21184-weik1fAThZGYFFhPG6tFKA]-[server.ccl.net> X-Original-From: Andreas Klamt Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=ISO-8859-1; format=flowed Date: Thu, 09 Sep 2010 04:33:53 +0200 MIME-Version: 1.0 Sent to CCL by: Andreas Klamt [klamt|,|cosmologic.de] Dear William, I do not know the details of Gaussian. In general the entropy change of solvation will be hidden in the non-electrostatic contibutions to Epcm. This is already the difference to the gasphase. Hence it is o.k. if you use the gasphase energy Egas Andreas Am 07.09.2010 22:59, schrieb William Flak williamflak|,|yahoo.com: > Sent to CCL by: William Flak [williamflak=-=yahoo.com] > Dear All > Thanks so much for your reply. > I was studying each word in your replies, it was really helpful. I read more on this topic in physical chemistry textbooks. > I still have some questions, and sorry if I am going to take more from your time. > * Implicit solvation models account for entropy term. But entropy is not accounted in gas calculation (sure). But how Gaussian calculates delta G(solv) using SCFVAC keyword. As I know, this keyword does SCF in gas phase in addition to that one in solvent. I am a little bit confused, sorry, it means: > delta G(solv) = Gsolution - Ggas (original equation) > delta G(solv) = Epcm - Egas (from Gaussian website) > I mean, in Gaussian, entroy is accounted ONLY in PCM but not in gas phase. It is wrong, am I right? or Gaussian does computes entropy in gas phase as well (I can't see it in the output). > * As well, if I calculated Epcm and Egas and used delta G(solv) = Epcm - Egas equation, I would get different answer from delta G(solv) calculated using SCFVAC keyword. what is the source of this difference, am I missing something? > Thanks in advance > W. Flak > > > --- On Mon, 9/6/10, Michael K. Gilson mgilson-#-ucsd.edu wrote: > >> From: Michael K. Gilson mgilson-#-ucsd.edu >> Subject: CCL:G: Gsolv - pKa - Frequency >> To: "Flak, William " >> Date: Monday, September 6, 2010, 2:53 PM >> >> Sent to CCL by: "Michael K. Gilson" [mgilson_-_ucsd.edu] >> I agree with Andreas that, if an implicit solvent >> model already >> implicitly accounts for changes in vibrational entropy on >> solvation, one >> needs to be careful about double-counting this >> contribution. just for >> completeness, I'd mention that, when the solute is really >> flexible, as >> for a peptide, one would still want to think about possible >> changes in >> entropy due to shifts in conformational distributions due >> to solvation. >> >> Regards, >> Mike >> >> On 9/6/2010 12:07 AM, Andreas Klamt klamt**cosmologic.de >> wrote: >>> Sent to CCL by: Andreas Klamt [klamt,+,cosmologic.de] >>> Hi all together, >>> >>> I think that Chris is quite right in most of his >> arguments, and >>> definitely Mike is right as well in saying that the >> partial molar >>> entropy is thermodynamically well defined and that it >> can be >>> considerably different in solution compared to the >> ideal gas. >>> But this difference is to first order already >> implicitly parameterized >>> into every continuum solvation model that is >> parameterized versus exp. >>> dG_solv. data. Since these data do include the entropy >> change, the >>> latter is also implicitly included into the >> parameterized solvation >>> models, not based on a frequency change, but via >> surface proportional >>> corrections. >>> >>> If you try to add the same via frequency based >> corrections (which are >>> not well defined, as I mentioned earlier and as Chris >> mentioned in >>> detail), you can only make things worse! >>> >>> In a solvation model which takes into account >> temperature dependence, as >>> in COSMO-RS, you can quantify the included partial >> molar entropy of >>> solvation based on the temperature derivative of >> dG_solv. >>> If you would like to develop a solvation model which >> is open for the >>> explicit addition of solvation entropy, you would have >> to do that based >>> on the the enthalpy (heat) of solvation, but there are >> much less exp. >>> data available for dH-solv than for dG_solv, and few >> people are >>> interested in dH_solv. The only situation for which >> lots of well measure >>> dG_solv ad dH_solv data are available, is >> self-solvation, which is >>> nothing else than free energy of vaporization (i.e. >> ln(vapor pressure) >>> and heat of vaporization). It should be noted that >> COSMO-RS describes >>> dG_vap and dH_vap consistently as self-solvation. >>> >>> Regarding your pKa problem (as for any reaction >> calculation) this means: >>> - Do the best gas phase calculation as you can afford, >> incl. gas-phase >>> entropy change, and then add the solvation free >> energies of educts and >>> products (with the right sign). >>> - Or use a parameterized pKa model directly based on >> the solution phase >>> energy difference of protonated and deprotonated >> species. >>> Hope this helps. >>> >>> Andreas >>> >>> >>> >>> >>> >>> Am 05.09.2010 14:57, schrieb W Flak williamflak- >> -yahoo.com: >>>> Sent to CCL by: "W Flak" >> [williamflak]![yahoo.com] >>>> Dear CCL >>>> I got some questions about pKa calculation hoping >> to get a help here. >>>> * First of all, on G03 help page, it says >> Gsolvation=EPCMEgas, but if I >>>> compared delta Gsolv obtained by SCFVAC with those >> obtained by carrying out two >>>> separate jobs, I'd get difference. Why? >>>> Example: >>>> by SCFVAC >>>> DeltaG (solv) (kcal/mol) = -10.26 >>>> By two separated jobs: >>>> deta Gsolv = Epcm - Egas = -15.49 >>>> >>>> * Is the entropy of a molecule in gas phase >> different from that in a solution? >>>> if yes, please direct me to the undergraduate book >> I should read >>>> * I read many posts on pKa calculation and found >> some people (as Andreas >>>> Klamt,2006) recommended not to include frequency >> in pKa calculation, and the >>>> others include it. What do you recommend? >>>> >>>> * In G.A.A. Saracino et al. / Chemical Physics >> Letters 373 (2003) 411415 >>>> Gibbs energies have been estimated by single point >> HF/6-31+G(d,p) calculations >>>> at geometries optimised in aqueous solution at the >> PBE0/6-31+G(d,p) level. How >>>> they calculated frequency at level differs from >> the optimization level? >>>> Any kind of help would be appreciated >>>> W. Flak> >>>> >>>> >> >> -- >> Michael K. Gilson, M.D., Ph.D. >> Professor >> Skaggs School of Pharm. and Pharm. Sci. >> University of California San Diego >> 9500 Gilman Drive, MC 0736 >> La Jolla, California, 92093-0736 >> Office: 858-822-0622 >> http://pharmacy.ucsd.edu/faculty/Gilson.shtml >> >> >> >> -= This is automatically added to each message by the >> mailing script =- >> To recover the email address of the author of the message, >> please change >> the strange characters on the top line to the () sign. You >> can also> >> E-mail to subscribers: CHEMISTRY() ccl.net >> or use: >> > >> E-mail to administrators: CHEMISTRY-REQUEST() ccl.net >> or use> > > -- PD. Dr. Andreas Klamt CEO / Geschäftsführer COSMOlogic GmbH& Co. KG Burscheider Strasse 515 D-51381 Leverkusen, Germany phone +49-2171-731681 fax +49-2171-731689 e-mail klamt*cosmologic.de web www.cosmologic.de HRA 20653 Amtsgericht Koeln, GF: Dr. Andreas Klamt Komplementaer: COSMOlogic Verwaltungs GmbH HRB 49501 Amtsgericht Koeln, GF: Dr. Andreas Klamt