This prob= lem comes up on CCL about once every month. The most likely cause is = the amount of scratch space needed in a frequency calculation. Are yo= u running on a 32 bit machine? If so you can only write 16 Gb of info= rmation in a scratch file. You have already mentioned that you have e= xtended the rwf space. Did you change the second line to something li= ke %rwf=3Da,1800mb,b,1800mb, c,1800mb etc. on out to h=3D1800mb? = ; If so you now are at the limit. So now look in the place where this= information is being stored. In about 10 minutes of execution time y= ou will see that the files a……h are now full. Type someth= ing like ls –l |more and you can read each files size. If they = are full there is not much else you can do other than find a 64 bit m= achine, or else use a program that doesn’t write scratch files in thi= s way.

Regards, Dave Close= .

From: owner-chemistry+closed=3D=3Detsu.edu::= ccl.net [mailto:owner-chemistry+closed=3D=3Detsu.edu::ccl.net] On Behalf = Of Jean Jules FIFEN julesfifen(_)gmail.com
Sent: Wednesday, M= arch 30, 2011 12:07 PM
To: Close, David M.
Subject: CCL= :G: Worries on gaussian calculations

Dear all,
I am = doing opt freq calculations on a molecule of 190 electrons, using the revis= ion B.01 of gaussian 03 software. The computation is done on a hexacore com= puter with 8GB of RAM memory. The first lines of my input look like:<= br>
%mem=3D2GB
%rwf=3Dmine.rwf
%nosave
%chk=3Dmine.chk
opt f= req b3lyp/6-31+g(d) test

The problem is that the job terminates unsu= ccessfully while computing frequencies with a message pasted below:
&nbs= p;There are 141 degrees of freedom in the 1st order CPHF.
   1= 38 vectors were produced by pass 0.
AX will form 138 AO Fock= derivatives at one time.
   138 vectors were produced by pass= 1.
   138 vectors were produced by pass 2.
&nb= sp; 138 vectors were produced by pass 3.
   138 ve= ctors were produced by pass 4.
   137 vectors were produ= ced by pass 5.
Erroneous write during file extend. write 32767 = instead of 4096
Probably out of disk space.
Write error in NtrExt1

Thereafter, I tried splitting my rwf file since the default.route = file is missing in this revision of gaussian 03. This does not solve the pr= oblem and lead to a problem of extending file.
I do not know what is wro= ng and, I would appreciate any help for solving this problem.

Many thanks in advance.
--

Jean Jules FIFEN,
PhD. = Student,
University of Douala,
Laboratory of fundamental Physics.

= --_000_9D6140C35ABD534F9C463F41FC3A9CC13E5D2E13etsums2etsuedu_-- From owner-chemistry@ccl.net Wed Mar 30 14:28:00 2011 From: "Wolf-D. Ihlenfeldt wdi=xemistry.com" To: CCL Subject: CCL: AW: 3D chemical coordinates to 2D image Message-Id: <-44249-110330134726-24427-pNyWC1sW9ima8J8Rp2H0kQ,+,server.ccl.net> X-Original-From: "Wolf-D. Ihlenfeldt" Content-Language: de Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii" Date: Wed, 30 Mar 2011 19:47:18 +0200 MIME-Version: 1.0 Sent to CCL by: "Wolf-D. Ihlenfeldt" [wdi=-=xemistry.com] The Cactvs toolkit (www.xemistry.com) can do it, too. It is for example used to generate the PubChem structure images. This is probably is quite similar to what you are planning to do. But it is not Open Source, either. However, I do not think you will find any such solution with capabilities (stereochemistry!) sufficient for a commercial or publishable academic project. More references: http://depth-first.com/articles/2008/03/26/five-open-tools-for-2d-structure- layout-aka-structure-diagram-generation/ And here a comparison with sobering results: http://baoilleach.webfactional.com/site_media/blog/sdg.html http://baoilleach.webfactional.com/site_media/blog/depict.html > > > Sent to CCL by: "Donald James Keidel" [dkeidel+*+emolecules.com] > Hi, > > I am looking for an open source software or API that will allow me to > convert 3D structures to 2D images (gif, png, jpg, etc.). I know I can > use Marvin molconvert, but I am looking for an open source equivalent > and could not find one searching the web. Any suggestion are welcome > and much appreciated. > > Thank you > > Don> To recover the email address of the author of the message, please > change From owner-chemistry@ccl.net Wed Mar 30 15:04:00 2011 From: "Miguel Quiliano Meza rifaximina^gmail.com" To: CCL Subject: CCL:G: resolving problems of "Exploring Chemistry with Electronic Structure Methods" page 168 Message-Id: <-44250-110330144035-30842-+bQAcghonfJT77YdtW2wWw-x-server.ccl.net> X-Original-From: Miguel Quiliano Meza Content-Type: multipart/alternative; boundary=002215048b97bb27f2049fb782ed Date: Wed, 30 Mar 2011 14:40:27 -0400 MIME-Version: 1.0 Sent to CCL by: Miguel Quiliano Meza [rifaximina:gmail.com] --002215048b97bb27f2049fb782ed Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Dear colleagues. Sorry If I disturb you again... with a simple question. Sincerely I don=B4t have much experience with Gaussian Because of your teachings I'm studying the cases in the book "Exploring Chemistry with Electronic Structure Methods". But I don=B4t know how to resolve the problem in the page 168 about computi= ng Enthalpies of reaction (chapter 8: Studying Chemical Reactions and Reactivity) The reaction is simple: H+ + H20 ----> H3O+ My doubts are: *How they got 0.02452 Hartees for H2O? I performed that calculations but only I obtained this: Linear equations converged to 9.666D-11 9.666D-10 after 5 iterations. SCF Done: E(RS-VWN) =3D -76.0950540648 a.u. after 6 cycles Convg =3D 0.2324D-09 28 Fock formations. S**2 =3D 0.0000 -V/T =3D 2.0058 E(RS-VWN) =3D -76.0950540648 This value is very near to the book for E, bu= t where is 0.02452??? Is always necessary perform single point calculations for these kind of calculations? why not geometry optimization? I say this because is the firs= t time that one works with one molecule. Is not it better to work with a stable molecule? Finally, Why the answer is -163.3 Kcal?? I have read this in the forum CCL: A + B ----> C C- (A+B) =3D enthalpy energy. If I perform the sum, the sum is not agree with the book. Because H+ =3D 0.0 H20 =3D -76.46241 H20+=3D -76.73422 I would be very grateful if someone can help me. Thank you in advance for your time and advices. M. --002215048b97bb27f2049fb782ed Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Dear colleagues.

Sorry If I disturb you again... with a simple quest= ion. Sincerely I don=B4t have much experience=A0 with Gaussian

Because of= your teachings I'm studying the cases in the book "= Exploring Chemistry with Electronic Structure Methods".

But I don=B4t know how to resolve the problem in the page 168 about com= puting Enthalpies of reaction (chapter 8: Studying Chemical Reactions and Reactivity)

The reaction is simple:

H+=A0=A0 += =A0 H20 ----> H3O+

My doubts are:

*How they got 0.02452 Ha= rtees for H2O? I performed that calculations but only I obtained=A0 this:
Linear equations conver= ged to 9.666D-11 9.666D-10 after=A0=A0=A0=A0 5 iterations.
=A0SCF Done:=A0 E(RS-VWN) =3D=A0 -76.0950540648=A0=A0=A0=A0 a.u. after=A0= =A0=A0 6 cycles
=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0 Convg=A0 =3D=A0=A0=A0 0.2324D-09=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 28 Foc= k formations.
=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0 S**2 =3D=A0 0.0000=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0 -V/T =3D=A0 2.0058

E(RS-VWN) =3D=A0 -76.0950540648 Thi= s value is very near to the book for E, but where is 0.02452= ???

Is always necessary perform single point calculations for these kind of=20 calculations? why not geometry optimization? I say this because is the=20 first time that one works with one molecule. Is not it better to work with a stable molecule?

Finally, Why the answer is -163.3 Kcal?? I have read this in the forum = CCL:

A + B ----> C
C- (A+B) =3D enthalpy energy.

If I p= erform the sum, the sum is not agree with the book. Because
H+ =3D 0.0<= br> H20 =3D -76.46241
H20+=3D -76.73422

I would be very grateful if = someone can help me.

Thank you in advance for your time and advices.=

M. --002215048b97bb27f2049fb782ed-- From owner-chemistry@ccl.net Wed Mar 30 17:07:00 2011 From: "Delwar Hossain hossaind2004^^yahoo.com" To: CCL Subject: CCL:G: resolving problems of "Exploring Chemistry with Electronic Structure Methods" page 168 Message-Id: <-44251-110330170422-26989-52JxvaxB5nO8We46dz3AnA|*|server.ccl.net> X-Original-From: Delwar Hossain Content-Type: multipart/alternative; boundary="0-627286374-1301519054=:82930" Date: Wed, 30 Mar 2011 14:04:14 -0700 (PDT) MIME-Version: 1.0 Sent to CCL by: Delwar Hossain [hossaind2004],[yahoo.com] --0-627286374-1301519054=:82930 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable You need to consider the following points: i) To get the value 0.02452=A0 for H20, please run the job for frequency ca= lculation.=20 ii) Even though for H+, the Ee=3D0, you need toconsider the translational e= nergy for H+ which is equal to 3/2RT. iii) You also need to run the job for H3O+ frequency calculation to obtain = the correction tem 0.03753. Include all these values to calculate the entalpy of reaction. Hope this may help. With regards, Delwar --- On Wed, 3/30/11, Miguel Quiliano Meza rifaximina^gmail.com wrote: > From: Miguel Quiliano Meza rifaximina^gmail.com Subject: CCL:G: resolving problems of "Exploring Chemistry with Electronic = Structure Methods" page 168 To: "Hossain, Delwar " Date: Wednesday, March 30, 2011, 1:40 PM Dear colleagues. Sorry If I disturb you again... with a simple question. Sincerely I don=B4t= have much experience=A0 with Gaussian Because of your teachings I'm studying the cases in the book "Exploring Che= mistry with Electronic Structure Methods". But I don=B4t know how to resolve the problem in the page 168 about computi= ng Enthalpies of reaction (chapter 8: Studying Chemical Reactions and React= ivity) The reaction is simple: H+=A0=A0 +=A0 H20 ----> H3O+ My doubts are: *How they got 0.02452 Hartees for H2O? I performed that calculations but on= ly I obtained=A0 this: Linear equations converged to 9.666D-11 9.666D-10 after=A0=A0=A0=A0 5 itera= tions. =A0SCF Done:=A0 E(RS-VWN) =3D=A0 -76.0950540648=A0=A0=A0=A0 a.u. after=A0= =A0=A0 6 cycles =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 Convg=A0 =3D=A0=A0=A0 0.2324D-09=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 28 Fock formations. =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 S**2 =3D=A0 0.0000=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 -V/T =3D=A0 2.0058 E(RS-VWN) =3D=A0 -76.0950540648 This value is very near to the book for E, = but where is 0.02452??? Is always necessary perform single point calculations for these kind of cal= culations? why not geometry optimization? I say this because is the first t= ime that one works with one molecule. Is not it better to work with a stabl= e molecule? Finally, Why the answer is -163.3 Kcal?? I have read this in the forum CCL: A + B ----> C C- (A+B) =3D enthalpy energy. If I perform the sum, the sum is not agree with the book. Because=20 H+ =3D 0.0 H20 =3D -76.46241 H20+=3D -76.73422=20 I would be very grateful if someone can help me. Thank you in advance for your time and advices. M. --0-627286374-1301519054=:82930 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
You need to consider the following point= s:

i) To get the value 0.02452 for H20, please run the job for freq= uency calculation.
ii) Even though for H+, the Ee=3D0, you need toconsi= der the translational energy for H+ which is equal to 3/2RT.

iii) You also need to run the job for H3O+ frequency calculation to ob= tain the correction tem 0.03753.

Include all these values to calculate the entalpy of reaction.

Hope this may help.

With regards,

Delwar

--- On Wed, 3/30/11, Miguel Quiliano Meza rifaximina^gmail.com = <owner-chemistry,,ccl.net> wrote:

From: Miguel Quiliano Meza rifaximina^gmail.com &= lt;owner-chemistry,,ccl.net>
Subject: CCL:G: resolving problems of "Ex= ploring Chemistry with Electronic Structure Methods" page 168
To: "Hossa= in, Delwar " <hossaind2004,,yahoo.com>
Date: Wednesday, Mar= ch 30, 2011, 1:40 PM

Dear colleagues.

Sorry If I disturb you again= ... with a simple question. Sincerely I don=B4t have much experience = with Gaussian

Because of your teachings I'm studying the cases in the book "Exploring Chemistry with Electronic Structure Methods".
But I don=B4t know how to resolve the problem in the page 168 about compu= ting Enthalpies of reaction (chapter 8: Studying Chemical Reactions and Rea= ctivity)

The reaction is simple:

H+   + H20 -= ---> H3O+

My doubts are:

*How they got 0.02452 Hartees for= H2O? I performed that calculations but only I obtained this:

= Linear equations converged= to 9.666D-11 9.666D-10 after     5 iterations.<= BR style=3D"BACKGROUND-COLOR: rgb(255,255,0)"> SCF Done: E(RS-VWN) =3D -76.0950540648   &nb= sp; a.u. after    6 cycles
=            Convg = =3D    0.2324D-09       &= nbsp;            28 = Fock formations.
     &= nbsp;        S**2 =3D 0.0000 =             &nb= sp;    -V/T =3D 2.0058

E(RS-VW= N) =3D -76.0950540648 This value is very near to the book for E, but = where is 0.02452???

Is always necessary perform single= point calculations for these kind of calculations? why not geometry optimi= zation? I say this because is the first time that one works with one molecu= le. Is not it better to wor= k with a stable molecule?

Finally, Why the answer is -= 163.3 Kcal?? I have read this in the forum CCL:

A + B ----> C
= C- (A+B) =3D enthalpy energy.

If I perform the sum, the sum is not a= gree with the book. Because
H+ =3D 0.0
H20 =3D -76.46241
H20+=3D = -76.73422

I would be very grateful if someone can help me.

T= hank you in advance for your time and advices.

M.
--0-627286374-1301519054=:82930-- From owner-chemistry@ccl.net Wed Mar 30 17:51:00 2011 From: "Jean Jules FIFEN julesfifen]_[gmail.com" To: CCL Subject: CCL:G: Worries on gaussian calculations Message-Id: <-44252-110330161541-1632-SrDyitp2sii3Q6yep9sacA~!~server.ccl.net> X-Original-From: Jean Jules FIFEN Content-Type: multipart/alternative; boundary=001636eefe15c8dbcb049fb8d6d4 Date: Wed, 30 Mar 2011 21:15:33 +0100 MIME-Version: 1.0 Sent to CCL by: Jean Jules FIFEN [julesfifen=-=gmail.com] --001636eefe15c8dbcb049fb8d6d4 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Dear Dave Close, Thank you so much for your kindly help. I am running on a 64 bit machine. Regarding the explanation you pointed out= , maybe the problem could be the installed version, since I installed a 32-bi= t g03 on a 64 bit computer by forcing. However, I will look carefully after what you said and will keep you in touch. Best regards, On 30 March 2011 18:45, Close, David M. CLOSED*mail.etsu.edu < owner-chemistry#,#ccl.net> wrote: > This problem comes up on CCL about once every month. The most likely cau= se > is the amount of scratch space needed in a frequency calculation. Are yo= u > running on a 32 bit machine? If so you can only write 16 Gb of informati= on > in a scratch file. You have already mentioned that you have extended the > rwf space. Did you change the second line to something like > %rwf=3Da,1800mb,b,1800mb, c,1800mb etc. on out to h=3D1800mb? If so you= now > are at the limit. So now look in the place where this information is bei= ng > stored. In about 10 minutes of execution time you will see that the file= s > a=85=85h are now full. Type something like ls =96l |more and you can rea= d each > files size. If they are full there is not much else you can do other th= an > find a 64 bit machine, or else use a program that doesn=92t write scratch > files in this way. > > Regards, Dave Close. > > > > *From:* owner-chemistry+closed=3D=3Detsu.edu##ccl.net[mailto: > owner-chemistry+closed=3D=3Detsu.edu##ccl.net ] *On > Behalf Of *Jean Jules FIFEN julesfifen(_)gmail.com > *Sent:* Wednesday, March 30, 2011 12:07 PM > *To:* Close, David M. > *Subject:* CCL:G: Worries on gaussian calculations > > > > Dear all, > I am doing opt freq calculations on a molecule of 190 electrons, using th= e > revision B.01 of gaussian 03 software. The computation is done on a hexac= ore > computer with 8GB of RAM memory. The first lines of my input look like: > > %mem=3D2GB > %rwf=3Dmine.rwf > %nosave > %chk=3Dmine.chk > opt freq b3lyp/6-31+g(d) test > > The problem is that the job terminates unsuccessfully while computing > frequencies with a message pasted below: > There are 141 degrees of freedom in the 1st order CPHF. > 138 vectors were produced by pass 0. > AX will form 138 AO Fock derivatives at one time. > 138 vectors were produced by pass 1. > 138 vectors were produced by pass 2. > 138 vectors were produced by pass 3. > 138 vectors were produced by pass 4. > 137 vectors were produced by pass 5. > *Erroneous write during file extend. write 32767 instead of 4096 > Probably out of disk space. > Write error in NtrExt1* > > Thereafter, I tried splitting my rwf file since the default.route file is > missing in this revision of gaussian 03. This does not solve the problem = and > lead to a problem of extending file. > I do not know what is wrong and, I would appreciate any help for solving > this problem. > > Many thanks in advance. > -- > > Jean Jules FIFEN, > PhD. Student, > University of Douala, > Laboratory of fundamental Physics. > > > --=20 Jules. --001636eefe15c8dbcb049fb8d6d4 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable
Dear Dave Close,
Thank you so much for your kindly help= .
I am running on a 64 bit machine. Regarding the explanation you pointe= d out, maybe the problem could be the installed version, since I installed = a 32-bit g03 on a 64 bit computer by forcing. However, I will look carefull= y after what you said and will keep you in touch.

Best regards,

On 30 March 2011 18:45= , Close, David M. CLOSED*mail.etsu.edu= <owner-che= mistry#,#ccl.net> wrote:

This problem comes up on CCL= about once every month.=A0 The most likely cause is the amount of scratch = space needed in a frequency calculation.=A0 Are you running on a 32 bit mac= hine?=A0 If so you can only write 16 Gb of information in a scratch file.= =A0 You have already mentioned that you have extended the rwf space.=A0 Did= you change the second line to something like %rwf=3Da,1800mb,b,1800mb, c,1= 800mb=A0 etc. on out to h=3D1800mb?=A0 If so you now are at the limit.=A0 S= o now look in the place where this information is being stored.=A0 In about= 10 minutes of execution time you will see that the files a=85=85h are now = full.=A0 Type something like ls =96l |more and you can read each files size= .=A0 If they are full=A0 there is not much else you can do other than find = a 64 bit machine, or else use a program that doesn=92t write scratch files = in this way.

Regards, Dave Close.
=A0

From:= owner-chemistry+closed=3D=3Detsu.edu##ccl.net [mailto:<= a href=3D"mailto:owner-chemistry%2Bclosed" target=3D"_blank">owner-chemistr= y+closed=3D=3D= etsu.edu##ccl.net] On Behalf Of Jean Jules FIFEN julesfifen(_)gmail.com
Sent: Wednesday, March 30, 2011 12:07 PM
To: Close, David = M.
Subject: CCL:G: Worries on gaussian calculations
=A0
Dear all,
I am doing opt freq calculations on a molecule of 190 electron= s, using the revision B.01 of gaussian 03 software. The computation is done= on a hexacore computer with=A0 8GB of RAM memory. The first lines of my in= put look like:

%mem=3D2GB
%rwf=3Dmine.rwf
%nosave
%chk=3Dmine.chk
opt freq= b3lyp/6-31+g(d) test

The problem is that the job terminates unsucce= ssfully while computing frequencies with a message pasted below:
=A0Ther= e are 141 degrees of freedom in the 1st order CPHF.
=A0=A0 138 vectors were produced by pass=A0 0.
=A0AX will form 138 AO Fo= ck derivatives at one time.
=A0=A0 138 vectors were produced by pass=A0 = 1.
=A0=A0 138 vectors were produced by pass=A0 2.
=A0=A0 138 vectors = were produced by pass=A0 3.
=A0=A0 138 vectors were produced by pass=A0 4.
=A0=A0 137 vectors were p= roduced by pass=A0 5.
Erroneous write during file extend. write 32767= instead of 4096
Probably out of disk space.
Write error in NtrExt1

Thereafter, I tried splitting my rwf file since the default.route file is m= issing in this revision of gaussian 03. This does not solve the problem and= lead to a problem of extending file.
I do not know what is wrong and, I= would appreciate any help for solving this problem.

Many thanks in advance.
--
Jean Jules FIFEN,
Ph= D. Student,
University of Douala,
Laboratory of fundamental Physics.<= /span>

=A0

--
Jules.

--001636eefe15c8dbcb049fb8d6d4-- From owner-chemistry@ccl.net Wed Mar 30 22:19:00 2011 From: "Kang Xiaohui huixiaokang328() 163.com" To: CCL Subject: CCL: absolute hardness Message-Id: <-44253-110330221659-26261-oB4mxsLHohZUVKDDCjYRGw|-|server.ccl.net> X-Original-From: "Kang Xiaohui" Date: Wed, 30 Mar 2011 22:16:57 -0400 Sent to CCL by: "Kang Xiaohui" [huixiaokang328!^!163.com] Dear all I need some information on the molecular absolute hardness in my study, but I don't know how to calculate it and which data I need to compute in gaussion 09. Therefore, I need a detail computational process, formulas or examples on gaining the molecular absolute hardness. Any help will be appreciated, I am looking forward to your timely reply Sincerely yours From owner-chemistry@ccl.net Wed Mar 30 22:59:00 2011 From: "Geoffrey Hutchison geoffh- -pitt.edu" To: CCL Subject: CCL: 3D chemical coordinates to 2D image Message-Id: <-44254-110330220022-19950-UgyBqxyIXXY+CHIIwqk8Cw-x-server.ccl.net> X-Original-From: Geoffrey Hutchison Content-Transfer-Encoding: 8bit Content-type: text/plain; charset=windows-1252 Date: Wed, 30 Mar 2011 22:00:14 -0400 MIME-version: 1.0 (Apple Message framework v1084) Sent to CCL by: Geoffrey Hutchison [geoffh . pitt.edu] > I am looking for an open source software or API that will allow me to convert 3D structures to 2D images (gif, png, jpg, etc.). If I understand the question, you *already* have 3D coordinates that you feel are accurate (stereochemistry, etc.) and you just want a JPEG of a ball-and-stick model. You don't need to do a 2D structural diagram (which was how Wolf interpreted your question), correct? If so, there are probably dozens of ways to do this, although depending on your application, you may not want to bother. For example, if these images are just going to stay in a browser window, you might as well use Jmol or ChemDoodle's JavaScript library to give you a rotatable view in HTML. Other alternatives which can display nice 3D images and can be scripted: * Avogadro * Jmol(!) * Pymol * VMD � Heck, if you're willing to run POVRay to do the render, even Open Babel can turn your 3D coordinates into a POV input suitable to generate a JPG. Cheers, -Geoff --- Prof. Geoffrey Hutchison Assistant Professor, Department of Chemistry University of Pittsburgh http://hutchison.chem.pitt.edu/ Office: (412) 648-0492 From owner-chemistry@ccl.net Wed Mar 30 23:33:00 2011 From: "Peng Yun ericyunp]*[gmail.com" To: CCL Subject: CCL:G: About antiferromagnetic coupling Message-Id: <-44255-110330225927-16569-xpAcpMC5XycubwQc4AChTg%x%server.ccl.net> X-Original-From: "Peng Yun" Date: Wed, 30 Mar 2011 22:59:25 -0400 Sent to CCL by: "Peng Yun" [ericyunp(_)gmail.com] Thanks for Dr.Gorelsky's suggestion,but the problem faced now is we only have Gaussian package&GaussView.Is there any other solution to this or some references which can be helpful? Many thanks in advance. > Dear CCLers: > I'm new to Gaussian,so I try to reproduce some example at Gaussian's > website.But I'm confused about one.In the "Antiferromagnetic coupling" > example of gauss03--www.gaussian.com/g_tech/antiferr_g03.htm--it tries to > reorder the orbitals,and choose some orbitals changed to .What I'm > confused is the criterion that it choose the orbitals to be reordered.Why >they choose these orbitals to be reordered. >yes, that's indeed a confusing method. A much better (simpler and 100% >reliable) method is to take fragment orbitals and generate an >appropriate guess wavefunction. See Appendix II of the AOMix manual >(http://www.sg-chem.net/aomix/AOMix-manual.pdf) for details. >Best regards, > Serge Gorelsky