From owner-chemistry@ccl.net Thu Aug 20 00:52:01 2015 From: "Kaushik Hatua kaushikhatua#,#yahoo.in" To: CCL Subject: CCL: Excited state polarizability Message-Id: <-51600-150820004819-32518-K60LMPSn8lFDUXg2n9RhDA(-)server.ccl.net> X-Original-From: Kaushik Hatua Content-Type: multipart/alternative; boundary="_534FFA4B-DB46-4DB2-AE8B-39E6A22D0023_" Date: Thu, 20 Aug 2015 10:18:07 +0530 MIME-Version: 1.0 Sent to CCL by: Kaushik Hatua [kaushikhatua]=[yahoo.in] --_534FFA4B-DB46-4DB2-AE8B-39E6A22D0023_ Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="Windows-1252" Is it possible to calculate excited state polarizability in g09 Sent from Nokia Lumia = --_534FFA4B-DB46-4DB2-AE8B-39E6A22D0023_ Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="Windows-1252"
Is it possible to calculate excited state  po= larizability in g09

Sent from Nokia Lumia
= --_534FFA4B-DB46-4DB2-AE8B-39E6A22D0023_-- From owner-chemistry@ccl.net Thu Aug 20 06:02:00 2015 From: "Robert Molt r.molt.chemical.physics]^[gmail.com" To: CCL Subject: CCL:G: UV-Visible spectrum Message-Id: <-51601-150820001454-26705-4FCZf+o18et87gL/qlDHkQ[#]server.ccl.net> X-Original-From: Robert Molt Content-Type: multipart/alternative; boundary="------------050709080909040702020203" Date: Thu, 20 Aug 2015 00:14:46 -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. --------------050709080909040702020203 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit There are many ways to calculated electronic spectra. CIS is a very cheap, reasonable wavefunction methodology. You can also use TD-DFT (someone stated that range-separated functionals are better; this is not true for excited states, as the ground and excited states will have the same error and it will be subtracted off very commonly). As DFT is is often heavily parameterized, it will fail in some cases, but not others. Hence, sometimes people encourage comparing to experiment (although this somewhat defeats the point). The best methods are EOM-CCSD or MR-CI excited state calculations, depending on if dynamic or static correlation is expected to be the greater issue. These methods have the advantage is that they do not require any notion of comparing to experiment; they have no parameters, and are thus equally likely to do well on any system (aside the issue of static vs. dynamic correlation) because they are based on systematically moving to the exact wavefunction answer. Given that you are doing benzene, a highly symmetric molecule with few atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish to. Remember to use diffuse functions in your basis set, always, to describe excited states. On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com wrote: > Try TDDFT. Several functionals may do an excellent job for benzene, > especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. > Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may > also do a good job for benzene. The basis set you used may be too > small, but acceptable. Your really need an assessment for the > functionals, basis set etc, using the experimental spectra as the > reference. > ----From my experience in TDDFT calculations of the benzoic acid > derivatives (JPCA 2012). Hao-Bo Guo > > On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou > kaci.tiziouzou/./gmail.com > > wrote: > > Hi all, > > Can anyone share with me the procedure that I can use to get a > UV-VIS spectrum for Benzene. I am currently using the TD-SCF in > gaussian 09 with a 6-31G basis set (Hartree Fock) and my value is > way below the experimental. > > I must be doing something wrong!! > > Thanks in advance > > K.T > > -- 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 --------------050709080909040702020203 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit There are many ways to calculated electronic spectra.

CIS is a very cheap, reasonable wavefunction methodology.

You can also use TD-DFT (someone stated that range-separated functionals are better; this is not true for excited states, as the ground and excited states will have the same error and it will be subtracted off very commonly). As DFT is is often heavily parameterized, it will fail in some cases, but not others. Hence, sometimes people encourage comparing to experiment (although this somewhat defeats the point).

The best methods are EOM-CCSD or MR-CI excited state calculations, depending on if dynamic or static correlation is expected to be the greater issue. These methods have the advantage is that they do not require any notion of comparing to experiment; they have no parameters, and are thus equally likely to do well on any system (aside the issue of static vs. dynamic correlation) because they are based on systematically moving to the exact wavefunction answer.

Given that you are doing benzene, a highly symmetric molecule with few atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish to.

Remember to use diffuse functions in your basis set, always, to describe excited states.

On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com wrote:
Try TDDFT. Several functionals may do an excellent job for benzene, especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may also do a good job for benzene. The basis set you used may be too small, but acceptable. Your really need an assessment for the functionals, basis set etc, using the experimental spectra as the reference.
----From my experience in TDDFT calculations of the benzoic acid derivatives (JPCA 2012). Hao-Bo Guo

On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou kaci.tiziouzou/./gmail.com <owner-chemistry()ccl.net> wrote:
Hi all,

Can anyone share with me the procedure that I can use to get a UV-VIS spectrum for Benzene. I am currently using the TD-SCF in gaussian 09 with a 6-31G basis set (Hartree Fock) and my value is way below the experimental.

I must be doing something wrong!!

Thanks in advance

K.T


-- 
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
--------------050709080909040702020203-- From owner-chemistry@ccl.net Thu Aug 20 11:46:01 2015 From: "Hao-Bo Guo guohaobo!^!gmail.com" To: CCL Subject: CCL:G: UV-Visible spectrum Message-Id: <-51602-150820114416-9237-l3HXqVfz85jSYuyRUniL6g(-)server.ccl.net> X-Original-From: Hao-Bo Guo Content-Type: multipart/alternative; boundary=001a113a765cc1d6eb051dc00546 Date: Thu, 20 Aug 2015 11:44:11 -0400 MIME-Version: 1.0 Sent to CCL by: Hao-Bo Guo [guohaobo:-:gmail.com] --001a113a765cc1d6eb051dc00546 Content-Type: text/plain; charset=UTF-8 Hi Mr. Robert Molt, That's the reason I said an assessment of the functionals, basis sets etc is needed for TDDFT... I did not claim what is true or false, but based on my previous assessment the range-separated functionals that I used did show better results compared to others. In the assessment I also chose EOM-CCSD results as the gas-phase references; however, the spectra may typically be measured in solution(s) and the solvation effect must be taken into account. You can check this publication if interested: http://pubs.acs.org/doi/abs/10.1021/jp3084293 On Thu, Aug 20, 2015 at 12:14 AM, Robert Molt r.molt.chemical.physics]^[ gmail.com wrote: > There are many ways to calculated electronic spectra. > > CIS is a very cheap, reasonable wavefunction methodology. > > You can also use TD-DFT (someone stated that range-separated functionals > are better; this is not true for excited states, as the ground and excited > states will have the same error and it will be subtracted off very > commonly). As DFT is is often heavily parameterized, it will fail in some > cases, but not others. Hence, sometimes people encourage comparing to > experiment (although this somewhat defeats the point). > > The best methods are EOM-CCSD or MR-CI excited state calculations, > depending on if dynamic or static correlation is expected to be the greater > issue. These methods have the advantage is that they do not require any > notion of comparing to experiment; they have no parameters, and are thus > equally likely to do well on any system (aside the issue of static vs. > dynamic correlation) because they are based on systematically moving to the > exact wavefunction answer. > > Given that you are doing benzene, a highly symmetric molecule with few > atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish to. > > Remember to use diffuse functions in your basis set, always, to describe > excited states. > > > On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com wrote: > > Try TDDFT. Several functionals may do an excellent job for benzene, > especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. > Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may also > do a good job for benzene. The basis set you used may be too small, but > acceptable. Your really need an assessment for the functionals, basis set > etc, using the experimental spectra as the reference. > ----From my experience in TDDFT calculations of the benzoic acid > derivatives (JPCA 2012). Hao-Bo Guo > > On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou kaci.tiziouzou/./gmail.com > wrote: > >> Hi all, >> >> Can anyone share with me the procedure that I can use to get a UV-VIS >> spectrum for Benzene. I am currently using the TD-SCF in gaussian 09 with a >> 6-31G basis set (Hartree Fock) and my value is way below the experimental. >> >> I must be doing something wrong!! >> >> Thanks in advance >> >> K.T >> > > > -- > Dr. Robert Molt Jr.r.molt.chemical.physics/a\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 > > --001a113a765cc1d6eb051dc00546 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hi Mr. Robert Molt,
That's the reason I said an ass= essment of the functionals, basis sets etc is needed for TDDFT... I did not= claim what is true or false, but based on my previous assessment the range= -separated functionals that I used did show better results compared to othe= rs. In the assessment I also chose EOM-CCSD results as the gas-phase refere= nces; however, the spectra may typically be measured in solution(s) and the= solvation effect must be taken into account. You can check this publicatio= n if interested:
http://pubs.acs.org/doi/abs/10.1021/jp3084293

On Thu, Aug 20, 2015 at 12:14 = AM, Robert Molt r.molt.chemical.physics]^[gmai= l.com <owner-chemistry .. ccl.net> wrote:
=20 =20 =20
There are many ways to calculated electronic spectra.

CIS is a very cheap, reasonable wavefunction methodology.

You can also use TD-DFT (someone stated that range-separated functionals are better; this is not true for excited states, as the ground and excited states will have the same error and it will be subtracted off very commonly). As DFT is is often heavily parameterized, it will fail in some cases, but not others. Hence, sometimes people encourage comparing to experiment (although this somewhat defeats the point).

The best methods are EOM-CCSD or MR-CI excited state calculations, depending on if dynamic or static correlation is expected to be the greater issue. These methods have the advantage is that they do not require any notion of comparing to experiment; they have no parameters, and are thus equally likely to do well on any system (aside the issue of static vs. dynamic correlation) because they are based on systematically moving to the exact wavefunction answer.

Given that you are doing benzene, a highly symmetric molecule with few atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish to.

Remember to use diffuse functions in your basis set, always, to describe excited states.


On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com wrote:
Try TDDFT. Several functionals may do an excellent job for benzene, especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may also do a good job for benzene. The basis set you used may be too small, but acceptable. Your really need an assessment for the functionals, basis set etc, using the experimental spectra as the reference.
----From my experience in TDDFT calculations of the benzoic acid derivatives (JPCA 2012). Hao-Bo Guo

On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou kaci.tiziouzou/./gmail.com <owner-chemistry()ccl.net> wrote:
Hi all,

Can anyone share with me the procedure that I can use to get a UV-VIS spectrum for Benzene. I am currently using the TD-SCF in gaussian 09 with a 6-31G basis set (Hartree Fock) and my value is way below the experimental.

I must be doing something wrong!!

Thanks in advance

K.T


--=20
Dr. Robert Molt Jr.
=
r.molt.chemical.physics/a\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

--001a113a765cc1d6eb051dc00546-- From owner-chemistry@ccl.net Thu Aug 20 16:09:01 2015 From: "Robert Molt r.molt.chemical.physics!^!gmail.com" To: CCL Subject: CCL:G: UV-Visible spectrum Message-Id: <-51603-150820142127-16007-hUf/xn1d7Drf0aZ6EbEGzA:_:server.ccl.net> X-Original-From: Robert Molt Content-Type: multipart/alternative; boundary="------------060307010704010003030503" Date: Thu, 20 Aug 2015 14:21:19 -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. --------------060307010704010003030503 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Excited state energies subtract off the energies of the ground state. A bias in the ground state that is also present in the excited state is therefore not a problem; it's the same error on both sides. See the work of leaders in the field of DFT for numerical examples (Perdew, Head-Gordon, Truhlar, Trickey). It is not true that solvation effect *must *be taken into account. It is certainly nice to do so, but sometimes the solution effect is trivial or a constant bias. People have been publishing gas phase spectra for decades getting good results. It is nice to take into account the solvation effects...assuming one can. It is important not to trivialize how hard it is to get solvation effects *accurately*, rather than just pick a solvation model. On 8/20/15 11:44 AM, Hao-Bo Guo guohaobo!^!gmail.com wrote: > Hi Mr. Robert Molt, > That's the reason I said an assessment of the functionals, basis sets > etc is needed for TDDFT... I did not claim what is true or false, but > based on my previous assessment the range-separated functionals that I > used did show better results compared to others. In the assessment I > also chose EOM-CCSD results as the gas-phase references; however, the > spectra may typically be measured in solution(s) and the solvation > effect must be taken into account. You can check this publication if > interested: > http://pubs.acs.org/doi/abs/10.1021/jp3084293 > > On Thu, Aug 20, 2015 at 12:14 AM, Robert Molt > r.molt.chemical.physics]^[gmail.com > > wrote: > > There are many ways to calculated electronic spectra. > > CIS is a very cheap, reasonable wavefunction methodology. > > You can also use TD-DFT (someone stated that range-separated > functionals are better; this is not true for excited states, as > the ground and excited states will have the same error and it will > be subtracted off very commonly). As DFT is is often heavily > parameterized, it will fail in some cases, but not others. Hence, > sometimes people encourage comparing to experiment (although this > somewhat defeats the point). > > The best methods are EOM-CCSD or MR-CI excited state calculations, > depending on if dynamic or static correlation is expected to be > the greater issue. These methods have the advantage is that they > do not require any notion of comparing to experiment; they have no > parameters, and are thus equally likely to do well on any system > (aside the issue of static vs. dynamic correlation) because they > are based on systematically moving to the exact wavefunction answer. > > Given that you are doing benzene, a highly symmetric molecule with > few atoms, you could easily afford to do EOM-CCSD or MR-CI if you > wish to. > > Remember to use diffuse functions in your basis set, always, to > describe excited states. > > > On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com > wrote: >> Try TDDFT. Several functionals may do an excellent job for >> benzene, especially the range-separated functionals CAM-B3LYP, >> wB97XD, LC-wPBE. Others such as doubly hybrid B2PLYPD, and >> meta-GGA hybrid M06-2X, may also do a good job for benzene. The >> basis set you used may be too small, but acceptable. Your really >> need an assessment for the functionals, basis set etc, using the >> experimental spectra as the reference. >> ----From my experience in TDDFT calculations of the benzoic acid >> derivatives (JPCA 2012). Hao-Bo Guo >> >> On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou >> kaci.tiziouzou/./gmail.com >> > >> wrote: >> >> Hi all, >> >> Can anyone share with me the procedure that I can use to get >> a UV-VIS spectrum for Benzene. I am currently using the >> TD-SCF in gaussian 09 with a 6-31G basis set (Hartree Fock) >> and my value is way below the experimental. >> >> I must be doing something wrong!! >> >> Thanks in advance >> >> K.T >> >> > > -- > Dr. Robert Molt Jr. > r.molt.chemical.physics/a\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 > > -- 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 --------------060307010704010003030503 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit Excited state energies subtract off the energies of the ground state. A bias in the ground state that is also present in the excited state is therefore not a problem; it's the same error on both sides. See the work of leaders in the field of DFT for numerical examples (Perdew, Head-Gordon, Truhlar, Trickey).

It is not true that solvation effect must be taken into account. It is certainly nice to do so, but sometimes the solution effect is trivial or a constant bias. People have been publishing gas phase spectra for decades getting good results.

It is nice to take into account the solvation effects...assuming one can. It is important not to trivialize how hard it is to get solvation effects accurately, rather than just pick a solvation model.

On 8/20/15 11:44 AM, Hao-Bo Guo guohaobo!^!gmail.com wrote:
Hi Mr. Robert Molt,
That's the reason I said an assessment of the functionals, basis sets etc is needed for TDDFT... I did not claim what is true or false, but based on my previous assessment the range-separated functionals that I used did show better results compared to others. In the assessment I also chose EOM-CCSD results as the gas-phase references; however, the spectra may typically be measured in solution(s) and the solvation effect must be taken into account. You can check this publication if interested:
http://pubs.acs.org/doi/abs/10.1021/jp3084293

On Thu, Aug 20, 2015 at 12:14 AM, Robert Molt r.molt.chemical.physics]^[gmail.com <owner-chemistry-.-ccl.net> wrote:
There are many ways to calculated electronic spectra.

CIS is a very cheap, reasonable wavefunction methodology.

You can also use TD-DFT (someone stated that range-separated functionals are better; this is not true for excited states, as the ground and excited states will have the same error and it will be subtracted off very commonly). As DFT is is often heavily parameterized, it will fail in some cases, but not others. Hence, sometimes people encourage comparing to experiment (although this somewhat defeats the point).

The best methods are EOM-CCSD or MR-CI excited state calculations, depending on if dynamic or static correlation is expected to be the greater issue. These methods have the advantage is that they do not require any notion of comparing to experiment; they have no parameters, and are thus equally likely to do well on any system (aside the issue of static vs. dynamic correlation) because they are based on systematically moving to the exact wavefunction answer.

Given that you are doing benzene, a highly symmetric molecule with few atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish to.

Remember to use diffuse functions in your basis set, always, to describe excited states.


On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com wrote:
Try TDDFT. Several functionals may do an excellent job for benzene, especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may also do a good job for benzene. The basis set you used may be too small, but acceptable. Your really need an assessment for the functionals, basis set etc, using the experimental spectra as the reference.
----From my experience in TDDFT calculations of the benzoic acid derivatives (JPCA 2012). Hao-Bo Guo

On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou kaci.tiziouzou/./gmail.com <owner-chemistry()ccl.net> wrote:
Hi all,

Can anyone share with me the procedure that I can use to get a UV-VIS spectrum for Benzene. I am currently using the TD-SCF in gaussian 09 with a 6-31G basis set (Hartree Fock) and my value is way below the experimental.

I must be doing something wrong!!

Thanks in advance

K.T


-- 
Dr. Robert Molt Jr.
r.molt.chemical.physics/a\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


-- 
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
--------------060307010704010003030503-- From owner-chemistry@ccl.net Thu Aug 20 17:06:01 2015 From: "Marcel Swart marcel.swart],[icrea.cat" To: CCL Subject: CCL:G: UV-Visible spectrum Message-Id: <-51604-150820170447-11878-ViYhs617jaNeakZnzoInLw%a%server.ccl.net> X-Original-From: Marcel Swart Content-Type: multipart/alternative; boundary="Apple-Mail=_30BE8A70-72DE-4618-A2E5-8B99953CB5A8" Date: Thu, 20 Aug 2015 23:04:09 +0200 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2104\)) Sent to CCL by: Marcel Swart [marcel.swart^icrea.cat] --Apple-Mail=_30BE8A70-72DE-4618-A2E5-8B99953CB5A8 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 For Charge-Transfer states the range-separated functionals DO work = better. See e.g. the work of leaders in the field like Tozer, Kronik. See e.g.: Excited state surfaces in density functional theory: A new twist on an = old problem=20 P. Wiggins, J. A. G. Williams, and D. J. Tozer, J. Chem. Phys. 131 = 091101(1-4) (2009) TDDFT diagnostic testing and functional assessment for triazene = chromophores =20 M. J. G. Peach, C. R. Le Sueur, K. Ruud, M. Guillaume, and D. J. Tozer, = Phys. Chem. Chem. Phys. 11 4465-4470 (2009) =E2=80=9CExcitation Gaps of Finite-Sized Systems from Optimally-Tuned = Range-Separated Hybrid Functionals=E2=80=9D L. Kronik, T. Stein, S. Refaely-Abramson, R. Baer, J. Chem. Theo. Comp. = (Perspectives Article) 8, 1515 (2012) "Prediction of charge-transfer excitations in coumarin-based dyes using = a range-separated functional tuned from first principles=E2=80=9D T. Stein, L. Kronik, and R. Baer, J. Chem. Phys. 131, 244119 (2009) Comparing gas-phase computational results with experimental liquid-phase results is of course comparing apples with pears. This has been = demonstrated by many people working in the field of solvation, such as van Duijnen, = Tomasi, Jensen, Mikkelsen, Astrand, Kongsted, and many many more. Talking of van Duijnen, have you tried ZINDO for your excited state = energies? Especially with a polarizable force field for solvation (ZINDRF) this = can give you excellent results for organic molecules. Marcel > On 2015-08-20, at 20:21, Robert Molt = r.molt.chemical.physics!^!gmail.com wrote: >=20 > Excited state energies subtract off the energies of the ground state. = A bias in the ground state that is also present in the excited state is = therefore not a problem; it's the same error on both sides. See the work = of leaders in the field of DFT for numerical examples (Perdew, = Head-Gordon, Truhlar, Trickey). >=20 > It is not true that solvation effect must be taken into account. It is = certainly nice to do so, but sometimes the solution effect is trivial or = a constant bias. People have been publishing gas phase spectra for = decades getting good results. >=20 > It is nice to take into account the solvation effects...assuming one = can. It is important not to trivialize how hard it is to get solvation = effects accurately, rather than just pick a solvation model. >=20 > On 8/20/15 11:44 AM, Hao-Bo Guo guohaobo!^!gmail.com wrote: >> Hi Mr. Robert Molt, >> That's the reason I said an assessment of the functionals, basis sets = etc is needed for TDDFT... I did not claim what is true or false, but = based on my previous assessment the range-separated functionals that I = used did show better results compared to others. In the assessment I = also chose EOM-CCSD results as the gas-phase references; however, the = spectra may typically be measured in solution(s) and the solvation = effect must be taken into account. You can check this publication if = interested: >> http://pubs.acs.org/doi/abs/10.1021/jp3084293 = >>=20 >> On Thu, Aug 20, 2015 at 12:14 AM, Robert Molt = r.molt.chemical.physics]^[gmail.com = > wrote: >> There are many ways to calculated electronic spectra. >>=20 >> CIS is a very cheap, reasonable wavefunction methodology. >>=20 >> You can also use TD-DFT (someone stated that range-separated = functionals are better; this is not true for excited states, as the = ground and excited states will have the same error and it will be = subtracted off very commonly). As DFT is is often heavily parameterized, = it will fail in some cases, but not others. Hence, sometimes people = encourage comparing to experiment (although this somewhat defeats the = point). >>=20 >> The best methods are EOM-CCSD or MR-CI excited state calculations, = depending on if dynamic or static correlation is expected to be the = greater issue. These methods have the advantage is that they do not = require any notion of comparing to experiment; they have no parameters, = and are thus equally likely to do well on any system (aside the issue of = static vs. dynamic correlation) because they are based on systematically = moving to the exact wavefunction answer. >>=20 >> Given that you are doing benzene, a highly symmetric molecule with = few atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish = to. >>=20 >> Remember to use diffuse functions in your basis set, always, to = describe excited states. >>=20 >>=20 >> On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com = wrote: >>> Try TDDFT. Several functionals may do an excellent job for benzene, = especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. = Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may = also do a good job for benzene. The basis set you used may be too small, = but acceptable. Your really need an assessment for the functionals, = basis set etc, using the experimental spectra as the reference.=20 >>> ----=46rom my experience in TDDFT calculations of the benzoic acid = derivatives (JPCA 2012). Hao-Bo Guo >>>=20 >>> On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou = kaci.tiziouzou/./gmail.com > wrote: >>> Hi all, >>>=20 >>> Can anyone share with me the procedure that I can use to get a = UV-VIS spectrum for Benzene. I am currently using the TD-SCF in gaussian = 09 with a 6-31G basis set (Hartree Fock) and my value is way below the = experimental. >>>=20 >>> I must be doing something wrong!! >>>=20 >>> Thanks in advance >>>=20 >>> K.T >>>=20 >>=20 >> --=20 >> Dr. Robert Molt Jr. >> r.molt.chemical.physics/a\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 >>=20 >=20 > --=20 > Dr. Robert Molt Jr. > r.molt.chemical.physics a 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 _______________________________________________________ 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=_30BE8A70-72DE-4618-A2E5-8B99953CB5A8 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8 For Charge-Transfer states the range-separated functionals DO = work better.
See e.g. the work of leaders in the field = like Tozer, Kronik. See e.g.:

Excited state surfaces in density = functional theory: A new twist on an old problem 
P. = Wiggins, J. A. G. Williams, and D. J. Tozer, J. Chem. Phys. 131 = 091101(1-4) (2009)
TDDFT diagnostic testing and = functional assessment for triazene chromophores  
M. J. G. Peach, C. R. Le Sueur, K. Ruud, M. Guillaume, and D. = J. Tozer, Phys. Chem. Chem. Phys. 11 4465-4470 (2009)
=E2=80=9CExcitation Gaps of Finite-Sized = Systems from Optimally-Tuned Range-Separated Hybrid = Functionals=E2=80=9D
L. Kronik, T. Stein, S. = Refaely-Abramson, R. Baer, J. Chem. Theo. Comp. (Perspectives = Article) 8, 1515 (2012)
"Prediction of charge-transfer excitations in coumarin-based = dyes using a range-separated functional tuned from first = principles=E2=80=9D
T. Stein, L. Kronik, and R. = Baer, J. Chem. Phys. 131, 244119 (2009)

Comparing gas-phase = computational results with experimental liquid-phase
results is of course comparing apples with pears. This has = been demonstrated
by many people working in the = field of solvation, such as van Duijnen, Tomasi,
Jensen, Mikkelsen, Astrand, Kongsted, and many many = more.

Talking = of van Duijnen, have you tried ZINDO for your excited state = energies?
Especially with a polarizable force field = for solvation (ZINDRF) this can give you
excellent = results for organic molecules.

Marcel

On = 2015-08-20, at 20:21, Robert Molt r.molt.chemical.physics!^!gmail.com <owner-chemistry:ccl.net> wrote:

=20 =20
Excited state energies subtract off the energies of the ground state. A bias in the ground state that is also present in the excited state is therefore not a problem; it's the same error on both sides. See the work of leaders in the field of DFT for numerical examples (Perdew, Head-Gordon, Truhlar, Trickey).

It is not true that solvation effect must be taken = into account. It is certainly nice to do so, but sometimes the solution effect is trivial or a constant bias. People have been publishing gas phase spectra for decades getting good results.

It is nice to take into account the solvation effects...assuming one can. It is important not to trivialize how hard it is to get solvation effects accurately, rather than just = pick a solvation model.

On 8/20/15 11:44 AM, Hao-Bo Guo guohaobo!^!gmail.com = wrote:
Hi Mr. Robert Molt,
That's the reason I said an assessment of the functionals, basis sets etc is needed for TDDFT... I did not claim what is true or false, but based on my previous assessment the range-separated functionals that I used did show better results compared to others. In the assessment I also chose EOM-CCSD results as the gas-phase references; however, the spectra may typically be measured in solution(s) and the solvation effect must be taken into account. You can check this publication if interested:
http://pubs.acs.org/doi/abs/10.1021/jp3084293

On Thu, Aug 20, 2015 at 12:14 AM, Robert Molt r.molt.chemical.physics]^[gmail.com <owner-chemistry-.-ccl.net> wrote:
There = are many ways to calculated electronic spectra.

CIS is a very cheap, reasonable wavefunction = methodology.

You can also use TD-DFT (someone stated that range-separated functionals are better; this is not true for excited states, as the ground and excited states will have the same error and it will be subtracted off very commonly). As DFT is is often heavily parameterized, it will fail in some cases, but not others. Hence, sometimes people encourage comparing to experiment (although this somewhat defeats the point).

The best methods are EOM-CCSD or MR-CI excited state calculations, depending on if dynamic or static correlation is expected to be the greater issue. These methods have the advantage is that they do not require any notion of comparing to experiment; they have no parameters, and are thus equally likely to do well on any system (aside the issue of static vs. dynamic correlation) because they are based on systematically moving to the exact wavefunction answer.

Given that you are doing benzene, a highly symmetric molecule with few atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish to.

Remember to use diffuse functions in your basis set, always, to describe excited states.


On 8/19/15 10:45 PM, Hao-Bo Guo = guohaobo{:}gmail.com wrote:
Try TDDFT. Several functionals may = do an excellent job for benzene, especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may also do a good job for benzene. The basis set you used may be too small, but acceptable. Your really need an assessment for the functionals, basis set etc, using the experimental spectra as the reference.
----=46rom my experience in TDDFT calculations = of the benzoic acid derivatives (JPCA 2012). Hao-Bo Guo

On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou kaci.tiziouzou/./gmail.com <owner-chemistry()ccl.net> wrote:
Hi all,

Can anyone share with me the = procedure that I can use to get a UV-VIS spectrum for Benzene. I am currently using the TD-SCF in gaussian 09 with a 6-31G basis set (Hartree Fock) and my value is way below the experimental.

I must be doing something = wrong!!

Thanks in advance

K.T


--=20
Dr. Robert Molt Jr.
r.molt.chemical.physics/a\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


--=20
Dr. Robert Molt Jr.
r.molt.chemical.physics a 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


_______________________________________________________
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=_30BE8A70-72DE-4618-A2E5-8B99953CB5A8-- From owner-chemistry@ccl.net Thu Aug 20 23:17:01 2015 From: "Hao-Bo Guo guohaobo * gmail.com" To: CCL Subject: CCL:G: UV-Visible spectrum Message-Id: <-51605-150820213730-1328-CrBb7T2Hj1q2gv+hhBcqgg .. server.ccl.net> X-Original-From: Hao-Bo Guo Content-Type: multipart/alternative; boundary=001a11398aa04bad0c051dc84fcc Date: Thu, 20 Aug 2015 21:37:24 -0400 MIME-Version: 1.0 Sent to CCL by: Hao-Bo Guo [guohaobo!A!gmail.com] --001a11398aa04bad0c051dc84fcc Content-Type: text/plain; charset=UTF-8 Mr. Robert Molt, Thanks for telling me what is true and what is not. Nevertheless there are people studying how the solvents influence the electronic spectra, especially when the solvatochromic effect were involved. I know there is error cancellation for any selected functional, but this does not tell one which functional is good and which one is not, this is the reason for assessments. Hao-Bo On Thu, Aug 20, 2015 at 2:21 PM, Robert Molt r.molt.chemical.physics!^! gmail.com wrote: > Excited state energies subtract off the energies of the ground state. A > bias in the ground state that is also present in the excited state is > therefore not a problem; it's the same error on both sides. See the work of > leaders in the field of DFT for numerical examples (Perdew, Head-Gordon, > Truhlar, Trickey). > > It is not true that solvation effect *must *be taken into account. It is > certainly nice to do so, but sometimes the solution effect is trivial or a > constant bias. People have been publishing gas phase spectra for decades > getting good results. > > It is nice to take into account the solvation effects...assuming one can. > It is important not to trivialize how hard it is to get solvation effects > *accurately*, rather than just pick a solvation model. > > On 8/20/15 11:44 AM, Hao-Bo Guo guohaobo!^!gmail.com wrote: > > Hi Mr. Robert Molt, > That's the reason I said an assessment of the functionals, basis sets etc > is needed for TDDFT... I did not claim what is true or false, but based on > my previous assessment the range-separated functionals that I used did show > better results compared to others. In the assessment I also chose EOM-CCSD > results as the gas-phase references; however, the spectra may typically be > measured in solution(s) and the solvation effect must be taken into > account. You can check this publication if interested: > http://pubs.acs.org/doi/abs/10.1021/jp3084293 > > On Thu, Aug 20, 2015 at 12:14 AM, Robert Molt r.molt.chemical.physics]^[ > gmail.com wrote: > >> There are many ways to calculated electronic spectra. >> >> CIS is a very cheap, reasonable wavefunction methodology. >> >> You can also use TD-DFT (someone stated that range-separated functionals >> are better; this is not true for excited states, as the ground and excited >> states will have the same error and it will be subtracted off very >> commonly). As DFT is is often heavily parameterized, it will fail in some >> cases, but not others. Hence, sometimes people encourage comparing to >> experiment (although this somewhat defeats the point). >> >> The best methods are EOM-CCSD or MR-CI excited state calculations, >> depending on if dynamic or static correlation is expected to be the greater >> issue. These methods have the advantage is that they do not require any >> notion of comparing to experiment; they have no parameters, and are thus >> equally likely to do well on any system (aside the issue of static vs. >> dynamic correlation) because they are based on systematically moving to the >> exact wavefunction answer. >> >> Given that you are doing benzene, a highly symmetric molecule with few >> atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish to. >> >> Remember to use diffuse functions in your basis set, always, to describe >> excited states. >> >> >> On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com wrote: >> >> Try TDDFT. Several functionals may do an excellent job for benzene, >> especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. >> Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may also >> do a good job for benzene. The basis set you used may be too small, but >> acceptable. Your really need an assessment for the functionals, basis set >> etc, using the experimental spectra as the reference. >> ----From my experience in TDDFT calculations of the benzoic acid >> derivatives (JPCA 2012). Hao-Bo Guo >> >> On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou kaci.tiziouzou/./ >> gmail.com wrote: >> >>> Hi all, >>> >>> Can anyone share with me the procedure that I can use to get a UV-VIS >>> spectrum for Benzene. I am currently using the TD-SCF in gaussian 09 with a >>> 6-31G basis set (Hartree Fock) and my value is way below the experimental. >>> >>> I must be doing something wrong!! >>> >>> Thanks in advance >>> >>> K.T >>> >> >> >> -- >> Dr. Robert Molt Jr.r.molt.chemical.physics/a\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 >> >> > > -- > Dr. Robert Molt Jr.r.molt.chemical.physics a 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 > > --001a11398aa04bad0c051dc84fcc Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Mr. Robert Molt,

Thanks for telling= me what is true and what is not. Nevertheless there are people studying ho= w the solvents influence the electronic spectra, especially when the solvat= ochromic effect were involved. I know there is error cancellation for any s= elected functional, but this does not tell one which functional is good and= which one is not, this is the reason for assessments.

Hao-Bo<= br>

On Thu, = Aug 20, 2015 at 2:21 PM, Robert Molt r.molt.chemical.physics!^!gmail.com <owner-chemistry,,ccl.net> wrote:
=20 =20 =20
Excited state energies subtract off the energies of the ground state. A bias in the ground state that is also present in the excited state is therefore not a problem; it's the same error on both sides. See the work of leaders in the field of DFT for numerical examples (Perdew, Head-Gordon, Truhlar, Trickey).

It is not true that solvation effect must be taken into account. It is certainly nice to do so, but sometimes the solution effect is trivial or a constant bias. People have been publishing gas phase spectra for decades getting good results.

It is nice to take into account the solvation effects...assuming one can. It is important not to trivialize how hard it is to get solvation effects accurately, rather than just pick a solvation model.

On 8/20/15 11:44 AM, Hao-Bo Guo guohaobo!^!gmail.com wrote:

On Thu, Aug 20, 2015 at 12:14 AM, Robert Molt r.molt.chemical.physics]^[gmail.com <owner-chemistry-.-ccl.net> wrote:
There are many ways to calculated electronic spectra.

CIS is a very cheap, reasonable wavefunction methodology.

You can also use TD-DFT (someone stated that range-separated functionals are better; this is not true for excited states, as the ground and excited states will have the same error and it will be subtracted off very commonly). As DFT is is often heavily parameterized, it will fail in some cases, but not others. Hence, sometimes people encourage comparing to experiment (although this somewhat defeats the point).

The best methods are EOM-CCSD or MR-CI excited state calculations, depending on if dynamic or static correlation is expected to be the greater issue. These methods have the advantage is that they do not require any notion of comparing to experiment; they have no parameters, and are thus equally likely to do well on any system (aside the issue of static vs. dynamic correlation) because they are based on systematically moving to the exact wavefunction answer.

Given that you are doing benzene, a highly symmetric molecule with few atoms, you could easily afford to do EOM-CCSD or MR-CI if you wish to.

Remember to use diffuse functions in your basis set, always, to describe excited states.


On 8/19/15 10:45 PM, Hao-Bo Guo guohaobo{:}gmail.com wrote:
Try TDDFT. Several functionals may do an excellent job for benzene, especially the range-separated functionals CAM-B3LYP, wB97XD, LC-wPBE. Others such as doubly hybrid B2PLYPD, and meta-GGA hybrid M06-2X, may also do a good job for benzene. The basis set you used may be too small, but acceptable. Your really need an assessment for the functionals, basis set etc, using the experimental spectra as the reference.
----From my experience in TDDFT calculations of the benzoic acid derivatives (JPCA 2012). Hao-Bo Guo

On Wed, Aug 19, 2015 at 5:11 PM, Kaci Tiziouzou kaci.tiziouzou/./gmail.com <owner-chemi= stry()ccl.net> wrote:
Hi all,

Can anyone share with me the procedure that I can use to get a UV-VIS spectrum for Benzene. I am currently using the TD-SCF in gaussian 09 with a 6-31G basis set (Hartree Fock) and my value is way below the experimental.

I must be doing something wrong!!

Thanks in advance

K.T


--=20
Dr. Robert Molt Jr.
=
r.molt.chemical.physics/a\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


--=20
Dr. Robert Molt Jr.
r.=
molt.chemical.physics a 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

--001a11398aa04bad0c051dc84fcc--