From owner-chemistry@ccl.net Sun May 31 11:19:01 2015 From: "Kaushik Hatua kaushikhatua-x-yahoo.in" To: CCL Subject: CCL: Best DFT for transition elements Message-Id: <-51409-150531111535-7235-cAxdac+z2cmC44+ppphDfg|a|server.ccl.net> X-Original-From: Kaushik Hatua Content-Type: multipart/alternative; boundary="_D77CAB14-4B53-4BC4-9440-062B8131DD9D_" Date: Sun, 31 May 2015 20:44:58 +0530 MIME-Version: 1.0 Sent to CCL by: Kaushik Hatua [kaushikhatua-*-yahoo.in] --_D77CAB14-4B53-4BC4-9440-062B8131DD9D_ Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="Windows-1252" Can anybody suggest me for following 1. Best DFT for optimization of transition (1st and 2nd) row elements organ= ometallic compounds. 2. property evaluation such as dipole moment, magnetic moment, excited stat= e character, thermochemistry etc. 3. Whether we need all electron basis or ECP for property evaluation 4. Whether we need relativistic correction or not Any help would be appreciated. Thanks in advance. Sent from Nokia Lumia = --_D77CAB14-4B53-4BC4-9440-062B8131DD9D_ Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="Windows-1252"
Can anybody suggest me for following
1. Best DF= T for optimization of transition (1st and 2nd) row elements organometallic = compounds.
2. property evaluation such as dipole moment, magnetic moment= , excited state character, thermochemistry etc.
3. Whether we need all e= lectron basis or ECP for property evaluation
4. Whether we need relativi= stic correction or not

Any help would be appreciated. Thanks in adva= nce.

Sent from Nokia Lumia
= --_D77CAB14-4B53-4BC4-9440-062B8131DD9D_-- From owner-chemistry@ccl.net Sun May 31 11:54:00 2015 From: "Billy McCann thebillywayne-,-gmail.com" To: CCL Subject: CCL: Measuring Instantaneous Correlation of Individual Orbitals Message-Id: <-51410-150531111630-7338-zqPgfuMhpMuKJf8sZD/mkA__server.ccl.net> X-Original-From: Billy McCann Content-Type: text/plain; charset=UTF-8 Date: Sun, 31 May 2015 11:16:09 -0400 MIME-Version: 1.0 Sent to CCL by: Billy McCann [thebillywayne{=}gmail.com] Greetings All. This is a subject I've been considering for a while, but it seems I haven't a) found a way to express the problem to myself so that it becomes more clear to me and b) come across literature that deals with my line of questioning. If anyone can offer insight into this, it would be very much appreciated. As a background, I have some training in chemical physics, but am far from expert. So please bear with me if I expose my ignorance. :) I'd like to frame the discussion within the wavefunction interpretation of QM and canonical Hatree-Fock atomic orbitals and LCAO-MO level of theory. I'd like to, for now, leave aside density functional theory because I don't have much experience or insight into the nature of the exchange-correlation operators; I can't seem to get a systematic understanding of that particular operator in its various formulations. And it's this correlation energy which I'm curious about. That the operator contains both exchange, correlation, plus a correction to the kinetic energies of the Kohn-Sham orbitals confounds me even more when trying to understand it, not even mentioning double-hybrid DFA's. I know that brilliant scientists have worked on various density functional approximations, and I do not at all want to belittle their work. DFA is a great tools for physicists and chemists. Now, on to my questions. Regarding instantaneous, dynamical electron correlation, I understand that there are many ab initio methods which begin at the Hatree-Fock approximation, starting with a Slater determinant expanded to various numbers of basis functions, and then account for dynamical electron correlation in different ways, typically, from what I can understand, by the admixture of electronic states wherein n number of electrons have been promoted to higher energy orbitals. If I understand correctly, all methods begin from the HF approximation and correct for dynamical correlation by making a linear combination of Slater determinants by different methods. (Perhaps the electron propagator method and the use of Dyson orbitals represents an alternative approach that doesn't combine Slater determinants, but I'm unsure. I've read Ortiz's review and let's just say it's a little out of my depth. ;)) All of these methods measure the correlation energy of the entire system in question, i.e. the atom or molecule in question. But what I'm wondering about is the correlation energy of a *single* atomic or molecular orbital. Is it that comparing the HF orbital energy to, say, a corresponding orbital resulting from a CCSD(T) calculation would yield such an energy? I've pondered this question, but I've read others who say that this isn't entirely the case because HF does indeed account for some small degree of electron correlation, but only in an averaged way. (I think I remember reading this in Cramer's text.) Perhaps MC-SCF may provide such an answer, by measuring the coefficients of each determinant? So my question is two-fold: 1. How can the dynamical electron correlation energy of a single atomic or molecular orbital be measured? Can it even be done? 2. Is it possible to make a generalized statement such as, "Core electrons experience a greater degree of correlation because they are surrounded by more electrons," or "Valence electrons experience a greater degree of electron correlation because they are bound more loosely to the system, allowing their wavefunctions to fluctuate more freely,"? I'd appreciate any insight that anyone has or any references to the literature or textbooks. Also, if someone would like to reframe this question in terms of non-canonicalized HF orbitals or from a NAO/NBO viewpoint, that would be great as well. I hope I haven't embarrassed myself. Thanks for your attention, Billy Wayne -- Billy Wayne McCann, Ph.D. http://bwayne.sdf.org irc://irc.freenode.net:bwayne "There is nothing new under the sun." ~ Solomon From owner-chemistry@ccl.net Sun May 31 13:10:01 2015 From: "Marcel Swart marcel.swart++icrea.cat" To: CCL Subject: CCL: Best DFT for transition elements Message-Id: <-51411-150531130923-31908-9hPHMW+QA8/i/01J/WeMKw{=}server.ccl.net> X-Original-From: Marcel Swart Content-Type: multipart/alternative; boundary="Apple-Mail=_292937D3-DE45-4D15-A218-E600F9404FC1" Date: Sun, 31 May 2015 19:09:14 +0200 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\)) Sent to CCL by: Marcel Swart [marcel.swart||icrea.cat] --Apple-Mail=_292937D3-DE45-4D15-A218-E600F9404FC1 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 Have a look at Cramer and Truhlar=92s review in Phys. Chem. Chem. Phys., 2009,11, 10757-10816 http://dx.doi.org/10.1039/B907148B Spin states are tricky and only few can be trusted (Chem. Phys. Lett. = 2013, 580, 166-171) http://dx.doi.org/10.1016/j.cplett.2013.06.045 ECPs can not be used for nuclear properties (NMR etc.) nor spin states (http://dx.doi.org/10.1002/qua.24255). Relativistic corrections are small for first row = (http://dx.doi.org/10.1021/jp803441m), more important for second row. Marcel > On 2015-05-31, at 17:14, Kaushik Hatua kaushikhatua-x-yahoo.in = wrote: >=20 > Can anybody suggest me for following > 1. Best DFT for optimization of transition (1st and 2nd) row elements = organometallic compounds. > 2. property evaluation such as dipole moment, magnetic moment, excited = state character, thermochemistry etc. > 3. Whether we need all electron basis or ECP for property evaluation > 4. Whether we need relativistic correction or not >=20 > Any help would be appreciated. Thanks in advance. >=20 > Sent from Nokia Lumia _______________________________________________________ Prof. Marcel Swart ICREA Research Professor at Inst. Comput. Chem. Catal. (IQCC) Univ. Girona (Spain) Member of Young Academy of Europe www.yacadeuro.org Chair COST Action CM1305 (ECOSTBio) www.ecostbio.eu Organizer Girona Seminar 2016 www.gironaseminar.com web http://www.marcelswart.eu vCard addressbook://www.marcelswart.eu/MSwart.vcf --Apple-Mail=_292937D3-DE45-4D15-A218-E600F9404FC1 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 Have a look at Cramer and Truhlar=92s review in
Phys. Chem. Chem. Phys., 2009,11, 10757-10816
http://dx.doi.org/10.1039/B907148B

Spin states are tricky and = only few can be trusted (Chem. Phys. Lett. 2013, 580, = 166-171)
http://dx.doi.org/10.1016/j.cplett.2013.06.045

ECPs can not be used for = nuclear properties (NMR etc.)
nor spin states = (http://dx.doi.org/10.1002/qua.24255).

Relativistic corrections are small for = first row (http://dx.doi.org/10.1021/jp803441m),
more= important for second row.

Marcel

On = 2015-05-31, at 17:14, Kaushik Hatua kaushikhatua-x-yahoo.in = <owner-chemistry(0)ccl.net> wrote:

Can anybody suggest me = for following
1. Best DFT for optimization of transition = (1st and 2nd) row elements organometallic compounds.
2. = property evaluation such as dipole moment, magnetic moment, excited = state character, thermochemistry etc.
3. Whether we need = all electron basis or ECP for property evaluation
4. = Whether we need relativistic correction or not

Any help would be appreciated. Thanks in advance.

Sent from Nokia Lumia =

=
_______________________________________________________
Prof. Marcel Swart

ICREA = Research Professor at
Inst. Comput. Chem. Catal. (IQCC)
Univ. Girona (Spain)

Member of = Young Academy of Europe
www.yacadeuro.org
Chair COST Action CM1305 (ECOSTBio)
www.ecostbio.eu
Organizer Girona Seminar = 2016
www.gironaseminar.com

web
http://www.marcelswart.eu
vCard
addressbook://www.marcelswart.eu/MSwart.vcf






= --Apple-Mail=_292937D3-DE45-4D15-A218-E600F9404FC1-- From owner-chemistry@ccl.net Sun May 31 13:44:01 2015 From: "Robert Molt r.molt.chemical.physics---gmail.com" To: CCL Subject: CCL: Measuring Instantaneous Correlation of Individual Orbitals Message-Id: <-51412-150531133205-10810-C7G1mouVDJFEnY6ldvvgjg-x-server.ccl.net> X-Original-From: Robert Molt Content-Type: multipart/alternative; boundary="------------040202020605040904060807" Date: Sun, 31 May 2015 13:31:57 -0400 MIME-Version: 1.0 Sent to CCL by: Robert Molt [r.molt.chemical.physics|-|gmail.com] This is a multi-part message in MIME format. --------------040202020605040904060807 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit "Correlation" cannot be measured because "correlation" is not a "thing." A mistake often made is to say " Hartree-Fock *lacks *correlation." or "What's missing from Hartree-Fock? Correlation!" 1.) Correlation is sometimes operationally defined as the difference between the right energy and the HF energy (such that HF does not *lack *correlation; it's not a thing, it's the difference needed to get the right answer). 2.) The more theoretical definition of "correlation," (and more useful, IMO) is based on statistics. If P(AB)/P(A)/P(B)=1, then A and B are uncorrelated (I am speaking quickly and roughly here, see a statistics book for specifics). We can express the probability in terms of wavefunction, for our purposes. If we just have a single-determinant expression with orthogonal orbitals, the P(AB)/P(A)/P(B), where A and B are the orbitals, this equals 1. Thus, because of having a single-determinant expression with orthogonal orbitals, the probability function of electron 1 is not correlated with 2 (again, I am speaking quickly to get the essential idea across). 3.) Which thus leads to the union of both above logical points: correlation is adding more determinants to a reference wavefunction. #1 told us "You need to be better than HF" which logically means to complete the mathematical space of the solution set (more than one determinant); #2 said "You have to have the dependence of probability of measuring an electron be dependent on other electrons" which means you need a mathematical form greater than one determinant for the correlation to be non-existent. On 5/31/15 11:16 AM, Billy McCann thebillywayne-,-gmail.com wrote: > Sent to CCL by: Billy McCann [thebillywayne{=}gmail.com] > Greetings All. > > This is a subject I've been considering for a while, but it seems I > haven't a) found a way to express the problem to myself so that it > becomes more clear to me and b) come across literature that deals with > my line of questioning. > > If anyone can offer insight into this, it would be very much > appreciated. As a background, I have some training in chemical > physics, but am far from expert. So please bear with me if I expose my > ignorance. :) I'd like to frame the discussion within the wavefunction > interpretation of QM and canonical Hatree-Fock atomic orbitals and > LCAO-MO level of theory. > > I'd like to, for now, leave aside density functional theory because I > don't have much experience or insight into the nature of the > exchange-correlation operators; I can't seem to get a systematic > understanding of that particular operator in its various formulations. > And it's this correlation energy which I'm curious about. That the > operator contains both exchange, correlation, plus a correction to the > kinetic energies of the Kohn-Sham orbitals confounds me even more when > trying to understand it, not even mentioning double-hybrid DFA's. I > know that brilliant scientists have worked on various density > functional approximations, and I do not at all want to belittle their > work. DFA is a great tools for physicists and chemists. > > Now, on to my questions. > > Regarding instantaneous, dynamical electron correlation, I understand > that there are many ab initio methods which begin at the Hatree-Fock > approximation, starting with a Slater determinant expanded to various > numbers of basis functions, and then account for dynamical electron > correlation in different ways, typically, from what I can understand, > by the admixture of electronic states wherein n number of electrons > have been promoted to higher energy orbitals. If I understand > correctly, all methods begin from the HF approximation and correct for > dynamical correlation by making a linear combination of Slater > determinants by different methods. (Perhaps the electron propagator > method and the use of Dyson orbitals represents an alternative > approach that doesn't combine Slater determinants, but I'm unsure. > I've read Ortiz's review and let's just say it's a little out of my > depth. ;)) > > All of these methods measure the correlation energy of the entire > system in question, i.e. the atom or molecule in question. > > But what I'm wondering about is the correlation energy of a *single* > atomic or molecular orbital. Is it that comparing the HF orbital > energy to, say, a corresponding orbital resulting from a CCSD(T) > calculation would yield such an energy? I've pondered this question, > but I've read others who say that this isn't entirely the case because > HF does indeed account for some small degree of electron correlation, > but only in an averaged way. (I think I remember reading this in > Cramer's text.) Perhaps MC-SCF may provide such an answer, by > measuring the coefficients of each determinant? > > So my question is two-fold: > > 1. How can the dynamical electron correlation energy of a single > atomic or molecular orbital be measured? Can it even be done? > > 2. Is it possible to make a generalized statement such as, "Core > electrons experience a greater degree of correlation because they are > surrounded by more electrons," or "Valence electrons experience a > greater degree of electron correlation because they are bound more > loosely to the system, allowing their wavefunctions to fluctuate more > freely,"? > > I'd appreciate any insight that anyone has or any references to the > literature or textbooks. > > Also, if someone would like to reframe this question in terms of > non-canonicalized HF orbitals or from a NAO/NBO viewpoint, that would > be great as well. > > I hope I haven't embarrassed myself. > > Thanks for your attention, > Billy Wayne > > -- > Billy Wayne McCann, Ph.D. > http://bwayne.sdf.org > irc://irc.freenode.net:bwayne > > "There is nothing new under the sun." ~ Solomon> > -- Dr. Robert Molt Jr. r.molt.chemical.physics(-)gmail.com Nigel Richards Research Group Department of Chemistry & Chemical Biology Indiana University-Purdue University Indianapolis LD 326 402 N. Blackford St. Indianapolis, IN 46202 --------------040202020605040904060807 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit "Correlation" cannot be measured because "correlation" is not a "thing."

A mistake often made is to say " Hartree-Fock lacks correlation." or "What's missing from Hartree-Fock? Correlation!"

1.) Correlation is sometimes operationally defined as the difference between the right energy and the HF energy (such that HF does not lack correlation; it's not a thing, it's the difference needed to get the right answer).

2.) The more theoretical definition of "correlation," (and more useful, IMO) is based on statistics. If P(AB)/P(A)/P(B)=1, then A and B are uncorrelated (I am speaking quickly and roughly here, see a statistics book for specifics). We can express the probability in terms of wavefunction, for our purposes. If we just have a single-determinant expression with orthogonal orbitals, the P(AB)/P(A)/P(B), where A and B are the orbitals, this equals 1. Thus, because of having a single-determinant expression with orthogonal orbitals, the probability function of electron 1 is not correlated with 2 (again, I am speaking quickly to get the essential idea across).

3.) Which thus leads to the union of both above logical points: correlation is adding more determinants to a reference wavefunction. #1 told us "You need to be better than HF" which logically means to complete the mathematical space of the solution set (more than one determinant); #2 said "You have to have the dependence of probability of measuring an electron be dependent on other electrons" which means you need a mathematical form greater than one determinant for the correlation to be non-existent.

On 5/31/15 11:16 AM, Billy McCann thebillywayne-,-gmail.com wrote:
Sent to CCL by: Billy McCann [thebillywayne{=}gmail.com]
Greetings All.

This is a subject I've been considering for a while, but it seems I
haven't a) found a way to express the problem to myself so that it
becomes more clear to me and b) come across literature that deals with
my line of questioning.

If anyone can offer insight into this, it would be very much
appreciated. As a background, I have some training in chemical
physics, but am far from expert. So please bear with me if I expose my
ignorance. :) I'd like to frame the discussion within the wavefunction
interpretation of QM and canonical Hatree-Fock atomic orbitals and
LCAO-MO level of theory.

I'd like to, for now, leave aside density functional theory because I
don't have much experience or insight into the nature of the
exchange-correlation operators; I can't seem to get a systematic
understanding of that particular operator in its various formulations.
And it's this correlation energy which I'm curious about. That the
operator contains both exchange, correlation, plus a correction to the
kinetic energies of the Kohn-Sham orbitals confounds me even more when
trying to understand it, not even mentioning double-hybrid DFA's. I
know that brilliant scientists have worked on various density
functional approximations, and I do not at all want to belittle their
work. DFA is a great tools for physicists and chemists.

Now, on to my questions.

Regarding instantaneous, dynamical electron correlation, I understand
that there are many ab initio methods which begin at the Hatree-Fock
approximation, starting with a Slater determinant expanded to various
numbers of basis functions, and then account for dynamical electron
correlation in different ways, typically, from what I can understand,
by the admixture of electronic states wherein n number of electrons
have been promoted to higher energy orbitals. If I understand
correctly, all methods begin from the HF approximation and correct for
dynamical correlation by making a linear combination of Slater
determinants by different methods. (Perhaps the electron propagator
method and the use of Dyson orbitals represents an alternative
approach that doesn't combine Slater determinants, but I'm unsure.
I've read Ortiz's review and let's just say it's a little out of my
depth. ;))

All of these methods measure the correlation energy of the entire
system in question, i.e. the atom or molecule in question.

But what I'm wondering about is the correlation energy of a *single*
atomic or molecular orbital.  Is it that comparing the HF orbital
energy to, say, a corresponding orbital resulting from a CCSD(T)
calculation would yield such an energy?  I've pondered this question,
but I've read others who say that this isn't entirely the case because
HF does indeed account for some small degree of electron correlation,
but only in an averaged way. (I think I remember reading this in
Cramer's text.) Perhaps MC-SCF may provide such an answer, by
measuring the coefficients of each determinant?

So my question is two-fold:

1. How can the dynamical electron correlation energy of a single
atomic or molecular orbital be measured? Can it even be done?

2. Is it possible to make a generalized statement such as, "Core
electrons experience a greater degree of correlation because they are
surrounded by more electrons," or "Valence electrons experience a
greater degree of electron correlation because they are bound more
loosely to the system, allowing their wavefunctions to fluctuate more
freely,"?

I'd appreciate any insight that anyone has or any references to the
literature or textbooks.

Also, if someone would like to reframe this question in terms of
non-canonicalized HF orbitals or from a NAO/NBO viewpoint, that would
be great as well.

I hope I haven't embarrassed myself.

Thanks for your attention,
Billy Wayne

--
Billy Wayne McCann, Ph.D.
http://bwayne.sdf.org
irc://irc.freenode.net:bwayne

"There is nothing new under the sun." ~ SolomonE-mail to subscribers: CHEMISTRY(-)ccl.net or use:
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-- 
Dr. Robert Molt Jr.
r.molt.chemical.physics(-)gmail.com
Nigel Richards Research Group
Department of Chemistry & Chemical Biology
Indiana University-Purdue University Indianapolis
LD 326
402 N. Blackford St.
Indianapolis, IN 46202
--------------040202020605040904060807-- From owner-chemistry@ccl.net Sun May 31 15:56:01 2015 From: "JC Womack jw5533 ~ my.bristol.ac.uk" To: CCL Subject: CCL: Measuring Instantaneous Correlation of Individual Orbitals Message-Id: <-51413-150531155427-29789-MFJMLIE0JeZ4Gww3QtcZSg-#-server.ccl.net> X-Original-From: JC Womack Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=utf-8 Date: Sun, 31 May 2015 20:54:15 +0100 MIME-Version: 1.0 Sent to CCL by: JC Womack [jw5533]=[my.bristol.ac.uk] These are interesting thoughts! You asked for some literature references. I would suggest looking at this excellent review: Hättig, C., Klopper, W., Köhn, A. & Tew, D. P. Explicitly Correlated Electrons in Molecules. Chem. Rev. 112, 4–74 (2012). http://pubs.acs.org/doi/abs/10.1021/cr200168z The review is about explicitly correlated electronic structure methods, but the introduction gives some useful insights into the nature of electron correlation. On 31/05/15 16:16, Billy McCann thebillywayne-,-gmail.com wrote: > > Sent to CCL by: Billy McCann [thebillywayne{=}gmail.com] > Greetings All. > > This is a subject I've been considering for a while, but it seems I > haven't a) found a way to express the problem to myself so that it > becomes more clear to me and b) come across literature that deals with > my line of questioning. > > If anyone can offer insight into this, it would be very much > appreciated. As a background, I have some training in chemical > physics, but am far from expert. So please bear with me if I expose my > ignorance. :) I'd like to frame the discussion within the wavefunction > interpretation of QM and canonical Hatree-Fock atomic orbitals and > LCAO-MO level of theory. > > I'd like to, for now, leave aside density functional theory because I > don't have much experience or insight into the nature of the > exchange-correlation operators; I can't seem to get a systematic > understanding of that particular operator in its various formulations. > And it's this correlation energy which I'm curious about. That the > operator contains both exchange, correlation, plus a correction to the > kinetic energies of the Kohn-Sham orbitals confounds me even more when > trying to understand it, not even mentioning double-hybrid DFA's. I > know that brilliant scientists have worked on various density > functional approximations, and I do not at all want to belittle their > work. DFA is a great tools for physicists and chemists. > > Now, on to my questions. > > Regarding instantaneous, dynamical electron correlation, I understand > that there are many ab initio methods which begin at the Hatree-Fock > approximation, starting with a Slater determinant expanded to various > numbers of basis functions, and then account for dynamical electron > correlation in different ways, typically, from what I can understand, > by the admixture of electronic states wherein n number of electrons > have been promoted to higher energy orbitals. If I understand > correctly, all methods begin from the HF approximation and correct for > dynamical correlation by making a linear combination of Slater > determinants by different methods. (Perhaps the electron propagator > method and the use of Dyson orbitals represents an alternative > approach that doesn't combine Slater determinants, but I'm unsure. > I've read Ortiz's review and let's just say it's a little out of my > depth. ;)) > > All of these methods measure the correlation energy of the entire > system in question, i.e. the atom or molecule in question. > > But what I'm wondering about is the correlation energy of a *single* > atomic or molecular orbital. Is it that comparing the HF orbital > energy to, say, a corresponding orbital resulting from a CCSD(T) > calculation would yield such an energy? I've pondered this question, > but I've read others who say that this isn't entirely the case because > HF does indeed account for some small degree of electron correlation, > but only in an averaged way. (I think I remember reading this in > Cramer's text.) Perhaps MC-SCF may provide such an answer, by > measuring the coefficients of each determinant? > > So my question is two-fold: > > 1. How can the dynamical electron correlation energy of a single > atomic or molecular orbital be measured? Can it even be done? > > 2. Is it possible to make a generalized statement such as, "Core > electrons experience a greater degree of correlation because they are > surrounded by more electrons," or "Valence electrons experience a > greater degree of electron correlation because they are bound more > loosely to the system, allowing their wavefunctions to fluctuate more > freely,"? > > I'd appreciate any insight that anyone has or any references to the > literature or textbooks. > > Also, if someone would like to reframe this question in terms of > non-canonicalized HF orbitals or from a NAO/NBO viewpoint, that would > be great as well. > > I hope I haven't embarrassed myself. > > Thanks for your attention, > Billy Wayne > > -- > Billy Wayne McCann, Ph.D. > http://bwayne.sdf.org > irc://irc.freenode.net:bwayne > > "There is nothing new under the sun." ~ Solomon> > -- James C. Womack PhD research student Centre for Computational Chemistry School of Chemistry University of Bristol BRISTOL BS8 1TS Email: jw5533-x-my.bristol.ac.uk Web: http://jcwomack.uk From owner-chemistry@ccl.net Sun May 31 17:20:00 2015 From: "Xing Yin xiy726_-_gmail.com" To: CCL Subject: CCL:G: transition density file generation Message-Id: <-51414-150531145520-27619-QO7nW/TN2E2pZaIukKysoQ||server.ccl.net> X-Original-From: Xing Yin Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=utf-8; format=flowed Date: Sun, 31 May 2015 14:55:07 -0400 MIME-Version: 1.0 Sent to CCL by: Xing Yin [xiy726[-]gmail.com] Hi Abbey, I was doing some related research. Just curious how did you make Gaussian generate the transition density files? The "cubegen" in G09 won't work with any density=transition keywords, If I simply use the "cube" keyword in g09, what I obtained is nothing but total SCF density. The output of density=scf and density=transition=1 is exactly the same. Thanks! On 5/30/2015 8:54 AM, Abbey Meprathu Philip abbeyphilip88 . gmail.com wrote: > Sent to CCL by: "Abbey Meprathu Philip" [abbeyphilip88[-]gmail.com] > Dear CCL members, > I am trying to calculate the transition density of a molecule. Using > Gaussian I am trying to generate the .cube file which could be used for > further calculation. I have input the co-ordinates of the molecule from the > crystal structure of the molecule and am using the following command to > generate the .cube file. > > %chk=NI-absorption_cube.chk > %mem=1GB > # td=(singlets,nstates=12) b3lyp/6-311++g(2d,2p) scrf= > (solvent=acetonitrile,pcm) geom=connectivity > scf=(convergence=6,maxcycle=512) > > As I am new to this type of calculation I am not much aware of the > commands to use. I want to calculate the transition density from the solid- > state crystal co-ordinates and don't want to use the solvent model. So what > command should I be using in order to calculate the transition density in > the solid state? Should I leave the scrf= (solvent= ) blank? > > Thank and regards, > Abbey> > -- Best Wishes, Xing From owner-chemistry@ccl.net Sun May 31 17:55:00 2015 From: "Marcel Swart marcel.swart---icrea.cat" To: CCL Subject: CCL: [DFT15poll] Annual popularity poll has started Message-Id: <-51415-150531170856-27087-yhMhXan0Z7OkL5HckAucvA*|*server.ccl.net> X-Original-From: Marcel Swart Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=utf-8 Date: Sun, 31 May 2015 23:08:47 +0200 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\)) Sent to CCL by: Marcel Swart [marcel.swart-x-icrea.cat] The 2015 edition of the Annual DFT Popularity Poll HAS STARTED. Your preferences for the poll can be entered at www.marcelswart.eu/dft-poll! This year's edition will mark a change with respect to the previous editions: a THIRD question is now added where participants can indicate for each functional on the list (both Primera and Segona Divisió 2015), what is their preference for a total of 11 properties (see also Rule #8): • Reaction barriers • Vibrational frequencies, Normal modes, Thermodynamics • Dispersion energy, π-π stacking • Hydrogen bonds • Excitation energies and chiroptical properties • Main group elements • Transition metals • Relativistic elements • NMR shieldings, NMR couplings • Geometries • Spin-state splittings For each of these properties one can choose between the following five preferences: ++ Love it ; + Like it ; 0 Neutral ; - Dislike it ; -- Hate it (only for the THIRD question) Best regards, Marcel Swart Matthias Bickelhaupt Miquel Duran _______________________________________________________ Prof. Marcel Swart ICREA Research Professor at Inst. Comput. Chem. Catal. (IQCC) Univ. Girona (Spain) Member of Young Academy of Europe www.yacadeuro.org Chair COST Action CM1305 (ECOSTBio) www.ecostbio.eu Organizer Girona Seminar 2016 www.gironaseminar.com web http://www.marcelswart.eu vCard addressbook://www.marcelswart.eu/MSwart.vcf