From owner-chemistry@ccl.net Mon Nov 16 01:29:01 2009 From: "Abhishek DuttaChowdhury abhishekdc\a/chem.iitb.ac.in" To: CCL Subject: CCL: one OPT error Message-Id: <-40689-091116010255-465-Hn8UzV3N3uiBa2JvLbsOYA!=!server.ccl.net> X-Original-From: "Abhishek DuttaChowdhury" Date: Mon, 16 Nov 2009 01:02:51 -0500 Sent to CCL by: "Abhishek DuttaChowdhury" [abhishekdc a chem.iitb.ac.in] Dear All, I am optimizing one molecule which donot have any crystal structure. My input file: %chk=cd_opt.chk %mem=1000MB #B3LYP/gen opt Nosymm Pseudo=Read formcheck GFINPUT IOp(6/7=3) #P GFPRINT 1 3 corodinates .... .... .... ... C H N O 0 6-31G* **** Si 0 LanL2DZ **** Si O LanL2DZ But the job stops and following lines are written at the end of output file: Rare condition: small coef for last iteration: 0.000D+00 Rare condition: small coef for last iteration: 0.000D+00 Rare condition: small coef for last iteration: 0.000D+00 Rare condition: small coef for last iteration: 0.000D+00 Restarting incremental Fock formation. What is reason behind it? Please help me in that regard. Many thanks in advance. Abhishek From owner-chemistry@ccl.net Mon Nov 16 02:53:01 2009 From: "Mahmoud A. A. Ibrahim m.ibrahim1982{:}yahoo.com" To: CCL Subject: CCL: one OPT error Message-Id: <-40690-091116025156-4095-uW/xQ0noPpIXXjXpDupVCA|server.ccl.net> X-Original-From: "Mahmoud A. A. Ibrahim" Content-Type: multipart/alternative; boundary="0-874985970-1258357899=:91396" Date: Sun, 15 Nov 2009 23:51:39 -0800 (PST) MIME-Version: 1.0 Sent to CCL by: "Mahmoud A. A. Ibrahim" [m.ibrahim1982:yahoo.com] --0-874985970-1258357899=:91396 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Dear Abhishek=20 I don't know the exact answer of your question, but I would like to pay you= r attention to onething, the next to last line: Si 0 LanL2DZ **** Si O LanL2DZ this should be 0 (zero) not O. Check it and run it again. I am not sure, bu= t at the same, your job terminated without any error, as I see. Do it and i= f you got the problem again, please send the complet input file. Sorry, one more thing, in your job, you asked for 1000MB, try to decrease t= he allocated memory size to 10MB for example, and see if it would solve the= prolbem. Send back Sincerely; M. Ibrahim=20 Mahmoud A. A. Ibrahim Current Address School of Chemistry, University of Manchester,=20 Oxford Road, Manchester, M13 9PL, United Kingdom. =20 Home Address =20 Chemistry Department, Faculty of Science,=20 Minia University,=20 Minia 61519,Egypt. Contact Information Email: m.ibrahim*_*compchem.net Email: m.ibrahim1982*_*yahoo.com Website: www.compchem.net Fax No.: +20862342601 =20 --- On Mon, 11/16/09, Abhishek DuttaChowdhury abhishekdca/chem.iitb.ac.in <= owner-chemistry*_*ccl.net> wrote: > From: Abhishek DuttaChowdhury abhishekdca/chem.iitb.ac.in Subject: CCL: one OPT error To: "Ibrahim, Mahmoud A. A. " Date: Monday, November 16, 2009, 6:02 AM Sent to CCL by: "Abhishek=A0 DuttaChowdhury" [abhishekdc a chem.iitb.ac.in] Dear All, I am optimizing one molecule which donot have any crystal structure. My in= put file: %chk=3Dcd_opt.chk %mem=3D1000MB =A0 #B3LYP/gen opt Nosymm Pseudo=3DRead formcheck GFINPUT IOp(6/7=3D3) #P GFPRINT 1 3 corodinates .... .... .... ... C H N O 0 6-31G* **** Si 0 LanL2DZ **** Si O LanL2DZ But the job stops and following lines are written at the end of output file= : Rare condition: small coef for last iteration:=A0 0.000D+00 Rare condition: small coef for last iteration:=A0 0.000D+00 Rare condition: small coef for last iteration:=A0 0.000D+00 Rare condition: small coef for last iteration:=A0 0.000D+00 Restarting incremental Fock formation. What is reason behind it? Please help me in that regard. Many thanks in adv= ance. Abhishek -=3D This is automatically added to each message by the mailing script =3D-=A0 =A0 =A0=A0 =A0 =A0Subscribe/Unsubscribe:=20 =A0 =A0 =A0Job: http://www.ccl.net/jobs=20=A0 =A0 =A0=0A=0A=0A --0-874985970-1258357899=:91396 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
Dear Abhishek
I don't know the exact answ= er of your question, but I would like to pay your attention to onething, th= e next to last line:
Si 0
LanL2DZ
****

Si O
LanL2DZ

this should= be 0 (zero) not O. Check it and run it again. I am not sure, but at the sa= me, your job terminated without any error, as I see. Do it and if you got t= he problem again, please send the complet input file.
Sorry, one more th= ing, in your job, you asked for 1000MB, try to decrease the allocated memor= y size to 10MB for example, and see if it would solve the prolbem.
Send = back
Sincerely;
M. Ibrahim

Mahmoud A. A. Ibrah= im
Current Address
School of Chemistry, University of Manchester, <= br>Oxford Road, Manchester, M13 9PL, United Kingdom.

= Home Address
Chemistry Department, Facul= ty of Science,
Minia University,
Minia 6= 1519,Egypt.

Contact Information
Email: m.ibrahim*_*compchem.net
Email: m.ibrahim1982*_*yahoo.comWebsite: www.compchem.net
Fax No.: +20862342601
=


--- On Mon, 11/16/09, Abhishek DuttaChowdhury abhis= hekdca/chem.iitb.ac.in <owner-chemistry*_*ccl.net> wrote:

From: Abhishek DuttaChowdhury abhis= hekdca/chem.iitb.ac.in <owner-chemistry*_*ccl.net>
Subject: CCL: one= OPT error
To: "Ibrahim, Mahmoud A. A. " <m.ibrahim1982*_*yahoo= .com>
Date: Monday, November 16, 2009, 6:02 AM


Sent to CCL by: "Abhishek  DuttaChowdhury" [abhishekdc a= chem.iitb.ac.in]
Dear All,
I am optimizing one molecule which donot= have any crystal structure. My input file:
%chk=3Dcd_opt.chk
%mem= =3D1000MB
  #B3LYP/gen opt Nosymm Pseudo=3DRead formcheck GFINPUT I= Op(6/7=3D3)
#P GFPRINT

1 3
corodinates
....
....
...= .
...

C H N O 0
6-31G*
****
Si 0
LanL2DZ
****
<= br>Si O
LanL2DZ



But the job stops and following lines are= written at the end of output file:
Rare condition: small coef for last iteration:  0.000D+00
Rare condition: small coef for last iterati= on:  0.000D+00
Rare condition: small coef for last iteration: = ; 0.000D+00
Rare condition: small coef for last iteration:  0.000D= +00
Restarting incremental Fock formation.



What is reaso= n behind it? Please help me in that regard. Many thanks in advance.

=



Abhishek



-=3D This is automatically added to= each message by the mailing script =3D-
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=0A= =0A=0A=0A --0-874985970-1258357899=:91396-- From owner-chemistry@ccl.net Mon Nov 16 04:05:01 2009 From: "Truong Tai truong.batai[#]chem.kuleuven.be" To: CCL Subject: CCL: Calculation of CMO-NICS Message-Id: <-40691-091116035830-21273-rj5zPdTk2MIxX34XXBHuwg ~~ server.ccl.net> X-Original-From: "Truong Tai" Date: Mon, 16 Nov 2009 03:58:26 -0500 Sent to CCL by: "Truong Tai" [truong.batai(-)chem.kuleuven.be] Dear CCL I am trying to calculate the CMO-NICS by using NBO progarmme. However, I do not know how to put a ghost atom in center position of my compound. When I put a ghost atom in my compound, NBO analysis can not be performed. There is a error in output file that NBO can not analyze because cannot determine AOs of ghost atom. Could you tell me how to fix this problem? Thank you very much for your help. From owner-chemistry@ccl.net Mon Nov 16 05:09:01 2009 From: "Pedro Silva pedros()ufp.edu.pt" To: CCL Subject: CCL:G: Mechanical and Electronic Embeddings Message-Id: <-40692-091116044837-12106-We1rYj/i04ZyQm/C9uFP7g]-[server.ccl.net> X-Original-From: Pedro Silva Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=ISO-8859-1 Date: Mon, 16 Nov 2009 09:48:24 +0000 MIME-Version: 1.0 Sent to CCL by: Pedro Silva [pedros{}ufp.edu.pt] > From what I have been told, ONIOM with electronic embedding takes for ever to complete, so that it will be more economical to use mechanic embedding oonly in the first stages of the geometry optimization (just like it is cheaper to perform initial QM optimization with a smallish, rather than large basis set) On Sun, Nov 15, 2009 at 1:40 PM, Morad El-Hendawy M80elhendawy|a|yahoo.com wrote: > > Sent to CCL by: "Morad =A0El-Hendawy" [M80elhendawy##yahoo.com] > Hey every body! > During my perusal to ONIOM pages on Gaussian website, http://www.gaussian= .com/g_tech/g_ur/k_oniom.htm, I found this statement: > > "For both minima and transition structures, it is usually more efficient = to first optimize using mechanical embedding and then perform a second opti= mization with electronic embedding starting from the resulting structure (r= ather than trying to use electronic embedding from the beginning)" > > I wonder if an expertise body tells us why it is preferred to start with = mechanical embedding then electronic embedding? Detailed answer with eviden= ces (i.e. published papers)is preferred and more appreciated. > Thanks a mil > Morad El-Hendawy > Ireland > > > > -=3D This is automatically added to each message by the mailing script = =3D-> =A0 =A0 =A0http://www.ccl.net/cgi-bin/ccl/send_ccl_message> =A0 =A0 =A0http://www.ccl.net/cgi-bin/ccl/send_ccl_message> =A0 =A0 =A0http://www.ccl.net/chemistry/sub_unsub.shtml> =A0 =A0 =A0http://www.ccl.net/spammers.txt> > > --=20 Pedro J. Silva Assistant Professor Universidade Fernando Pessoa Porto - Portugal http://www2.ufp.pt/~pedros/science/science.htm From owner-chemistry@ccl.net Mon Nov 16 08:07:01 2009 From: "Nuno A. G. Bandeira nuno.bandeira~!~ist.utl.pt" To: CCL Subject: CCL:G: Calculation of CMO-NICS Message-Id: <-40693-091116080519-4133-if+RSbH7qB7SYBxlZB+1eQ*|*server.ccl.net> X-Original-From: "Nuno A. G. Bandeira" Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Date: Mon, 16 Nov 2009 14:03:33 +0100 MIME-Version: 1.0 Sent to CCL by: "Nuno A. G. Bandeira" [nuno.bandeira _ ist.utl.pt] Em 16-11-2009 9:58, Truong Tai truong.batai[#]chem.kuleuven.be escreveu: > Sent to CCL by: "Truong Tai" [truong.batai(-)chem.kuleuven.be] > Dear CCL > > I am trying to calculate the CMO-NICS by using NBO progarmme. However, I do not know how to put a ghost atom in center position of my compound. When I put a ghost atom in my compound, NBO analysis can not be performed. There is a error in output file that NBO can not analyze because cannot determine AOs of ghost atom. > > Could you tell me how to fix this problem? > I have successfully used a combination of G98+NBO 5 in order to run it successfully with Gaussian a few years ago. I assume you could do it with G03/NBO5.G but I'm not sure. The essential commands are as follows: Specify these cards in the route section : Pop=(Full,NBORead) NMR IOP(10/46=1) (keep in mind that some IOP cards have changed since the G03 release) Signal your ring centre in the coordinates section like this: ... Cl -1.543657796 -1.377469902 -2.513209793 Cl -1.546420990 -1.382708299 2.511894719 Bq 0.0 0.0 0.0 After the basis sets/pseudopotential data, if any, you need to write this $NBO CMO NCS=0.001 $END Hope this will help you. -- Nuno A. G. Bandeira, AMRSC Laboratoire de Chimie LR6 Ecole Normale Superieure de Lyon 46, Allee d'Italie 69364 Lyon Cedex 07 - France http://cqb.fc.ul.pt/intheochem/nuno.html -- From owner-chemistry@ccl.net Mon Nov 16 10:24:01 2009 From: "Ba Tai Truong Truong.BaTai^^chem.kuleuven.be" To: CCL Subject: CCL:G: Calculation of CMO-NICS Message-Id: <-40694-091116102027-8662-DyARyF9wu2A/rYqfyJCU/A[#]server.ccl.net> X-Original-From: Ba Tai Truong Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=ISO-8859-1; DelSp="Yes"; format="flowed" Date: Mon, 16 Nov 2009 15:35:57 +0100 MIME-Version: 1.0 Sent to CCL by: Ba Tai Truong [Truong.BaTai^chem.kuleuven.be] Dear Bandeira Thank you very much for your help. I tried your guide, but it is impossible. I only try to calculate with benzen, as followed: *********** #n B3LYP/6-31+G* NMR pop=3Dnboread IOp(10/46=3D1) C6H6 benzene D6h //B3LYP/6-31+G* 0 1 C -0.69729405 1.20774583 0.00000000 C 0.69729107 1.20774832 0.00000000 C 1.39458646 0.00000000 0.00000000 C 0.69729377 -1.20774678 0.00000000 C -0.69729174 -1.20774707 0.00000000 C -1.39458675 -0.00000096 0.00000000 H -1.23949525 2.14686504 0.00000000 H 1.23949176 2.14686622 0.00000000 H 2.47898701 0.00000118 0.00000000 H 1.23949525 -2.14686504 0.00000000 H -1.23949176 -2.14686622 0.00000000 H -2.47898701 -0.00000118 0.00000000 Bq 0.00000000 0.00000000 0.00000000 Bq 0.00000000 0.00000000 1.00000000 $NBO CMO NCS=3D0.001 $END ************** But output file still has error as follow ******** Analyzing the SCF density Job title: C6H6 benzene D6h //B3LYP/6-31+G* Storage needed: 80004 in NPA, 64097 in NBO, 64330 in NLMO ( 190054400 available) Subroutine NAOANL could not find a s-type valence orbital on atom gh 13. IVAL : 1 0 0 0 M : 1 LA : 1 Missing valence orbital in SR NAOANL. Error: NBHALT ******** I will appreciate very much if you can give me more advices Thanks a lot. Quoting "Nuno A. G. Bandeira nuno.bandeira~!~ist.utl.pt" =20 : > > Sent to CCL by: "Nuno A. G. Bandeira" [nuno.bandeira _ ist.utl.pt] > Em 16-11-2009 9:58, Truong Tai truong.batai[#]chem.kuleuven.be escreveu: >> Sent to CCL by: "Truong Tai" [truong.batai(-)chem.kuleuven.be] >> Dear CCL >> >> I am trying to calculate the CMO-NICS by using NBO progarmme. =20 >> However, I do not know how to put a ghost atom in center position =20 >> of my compound. When I put a ghost atom in my compound, NBO =20 >> analysis can not be performed. There is a error in output file that =20 >> NBO can not analyze because cannot determine AOs of ghost atom. >> >> Could you tell me how to fix this problem? >> > > I have successfully used a combination of G98+NBO 5 in order to run it > successfully with Gaussian a few years ago. > > I assume you could do it with G03/NBO5.G but I'm not sure. > > The essential commands are as follows: > > Specify these cards in the route section : Pop=3D(Full,NBORead) NMR > IOP(10/46=3D1) > (keep in mind that some IOP cards have changed since the G03 release) > > Signal your ring centre in the coordinates section like this: > ... > Cl -1.543657796 -1.377469902 -2.513209793 > Cl -1.546420990 -1.382708299 2.511894719 > Bq 0.0 0.0 0.0 > > After the basis sets/pseudopotential data, if any, you need to write this > > $NBO CMO NCS=3D0.001 $END > > Hope this will help you. > > > -- > Nuno A. G. Bandeira, AMRSC > Laboratoire de Chimie LR6 > Ecole Normale Superieure de Lyon > 46, Allee d'Italie > 69364 Lyon Cedex 07 - France > http://cqb.fc.ul.pt/intheochem/nuno.html > -- > > > > -=3D This is automatically added to each message by the mailing script =3D= -> > > Truong Ba Tai Afdeling Kwantumchemie en Fysicochemie Celestijnenlaan 200F - bus 2404 3001 Heverlee, Belgium From owner-chemistry@ccl.net Mon Nov 16 12:51:00 2009 From: "Nuno A. G. Bandeira nuno.bandeira**ist.utl.pt" To: CCL Subject: CCL:G: Calculation of CMO-NICS Message-Id: <-40695-091116124930-14349-giQin7GEz65XNRzxVM89Pg~~server.ccl.net> X-Original-From: "Nuno A. G. Bandeira" Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Date: Mon, 16 Nov 2009 18:48:40 +0100 MIME-Version: 1.0 Sent to CCL by: "Nuno A. G. Bandeira" [nuno.bandeira^ist.utl.pt] Dear Truong, Like I said what works is the G98/NBO5.0 combination. I've never computed CMO-NICS values with G03 but you can however obtain NICS dissected per NLMO just by using the embedded NBO 3.1 in G03. All you need is to leave the NMR key in the route input and the NBO routines will pick up on that and list all the NLMO contributions for every chemical shielding including the ghost you specified. Otherwise if you really need the CMO-NICS values and use NBO 5.G I'd suggest you contact the NBO group to obtain support. My guess is you may have to modify their code and recompile. 16-11-2009 15:35, Ba Tai Truong Truong.BaTai^^chem.kuleuven.be : > > Sent to CCL by: Ba Tai Truong [Truong.BaTai^chem.kuleuven.be] > Dear Bandeira > > Thank you very much for your help. I tried your guide, but it is > impossible. > > I only try to calculate with benzen, as followed: > > *********** > #n B3LYP/6-31+G* NMR pop=nboread IOp(10/46=1) > > C6H6 benzene D6h //B3LYP/6-31+G* > > 0 1 > C -0.69729405 1.20774583 0.00000000 > C 0.69729107 1.20774832 0.00000000 > C 1.39458646 0.00000000 0.00000000 > C 0.69729377 -1.20774678 0.00000000 > C -0.69729174 -1.20774707 0.00000000 > C -1.39458675 -0.00000096 0.00000000 > H -1.23949525 2.14686504 0.00000000 > H 1.23949176 2.14686622 0.00000000 > H 2.47898701 0.00000118 0.00000000 > H 1.23949525 -2.14686504 0.00000000 > H -1.23949176 -2.14686622 0.00000000 > H -2.47898701 -0.00000118 0.00000000 > Bq 0.00000000 0.00000000 0.00000000 > Bq 0.00000000 0.00000000 1.00000000 > > $NBO CMO NCS=0.001 $END > > ************** > > But output file still has error as follow > ******** > Analyzing the SCF density > > Job title: C6H6 benzene D6h //B3LYP/6-31+G* > > Storage needed: 80004 in NPA, 64097 in NBO, > 64330 in NLMO ( 190054400 available) > > Subroutine NAOANL could not find a s-type valence orbital on atom gh 13. > IVAL : 1 0 0 0 M : 1 LA : 1 > > Missing valence orbital in SR NAOANL. > Error: NBHALT > ******** > > > I will appreciate very much if you can give me more advices > > Thanks a lot. > > > Quoting "Nuno A. G. Bandeira nuno.bandeira~!~ist.utl.pt" > : > >> >> Sent to CCL by: "Nuno A. G. Bandeira" [nuno.bandeira _ ist.utl.pt] >> Em 16-11-2009 9:58, Truong Tai truong.batai[#]chem.kuleuven.be escreveu: >>> Sent to CCL by: "Truong Tai" [truong.batai(-)chem.kuleuven.be] >>> Dear CCL >>> >>> I am trying to calculate the CMO-NICS by using NBO progarmme. >>> However, I do not know how to put a ghost atom in center position of >>> my compound. When I put a ghost atom in my compound, NBO analysis can >>> not be performed. There is a error in output file that NBO can not >>> analyze because cannot determine AOs of ghost atom. >>> >>> Could you tell me how to fix this problem? >>> >> >> I have successfully used a combination of G98+NBO 5 in order to run it >> successfully with Gaussian a few years ago. >> >> I assume you could do it with G03/NBO5.G but I'm not sure. >> >> The essential commands are as follows: >> >> Specify these cards in the route section : Pop=(Full,NBORead) NMR >> IOP(10/46=1) >> (keep in mind that some IOP cards have changed since the G03 release) >> >> Signal your ring centre in the coordinates section like this: >> ... >> Cl -1.543657796 -1.377469902 -2.513209793 >> Cl -1.546420990 -1.382708299 2.511894719 >> Bq 0.0 0.0 0.0 >> >> After the basis sets/pseudopotential data, if any, you need to write this >> >> $NBO CMO NCS=0.001 $END >> >> Hope this will help you. >> >> >> -- >> Nuno A. G. Bandeira, AMRSC >> Laboratoire de Chimie LR6 >> Ecole Normale Superieure de Lyon >> 46, Allee d'Italie >> 69364 Lyon Cedex 07 - France >> http://cqb.fc.ul.pt/intheochem/nuno.html >> --> >> >> > > > > Truong Ba Tai > Afdeling Kwantumchemie en Fysicochemie > Celestijnenlaan 200F - bus 2404 > 3001 Heverlee, Belgium > > > > -=his is automatically added to each message by the mailing script =-http://www.ccl.net/chemistry/sub_unsub.shtml> > Job: http://www.ccl.net/jobsConferences: > http://server.ccl.net/chemistry/announcements/conferences/> > > -- Nuno A. G. Bandeira, AMRSC Laboratoire de Chimie LR6 Ecole Normale Superieure de Lyon 46, Allee d'Italie 69364 Lyon Cedex 07 - France http://cqb.fc.ul.pt/intheochem/nuno.html -- From owner-chemistry@ccl.net Mon Nov 16 17:44:00 2009 From: "Soaring Bear soaringbear:+:yahoo.com" To: CCL Subject: CCL:G: Mechanical and Electronic Embeddings Message-Id: <-40696-091116021359-25637-n00+Rkv0puiljsa5u3KXIw(0)server.ccl.net> X-Original-From: Soaring Bear Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=iso-8859-1 Date: Sun, 15 Nov 2009 22:13:45 -0800 (PST) MIME-Version: 1.0 Sent to CCL by: Soaring Bear [soaringbear[a]yahoo.com] that makes sense because steric is more blunt of a force than electrostatic= =0A=0ASoaring Bear Ph.D. Pharmacology soaringbear at yahoo.com=0Ahttp://so= aringbear.com/nature/WeedsforNeeds.html=0Ahttp://www.nlm.nih.gov/mesh/prese= ntations/bear_2005_aug/index.htm=0Aauthor of http://HerbMed.org & http://He= rbInsight.com=0A=0A=0A--- On Sun, 11/15/09, Morad El-Hendawy M80elhendawy|a= |yahoo.com wrote:=0A=0A> Sent to CCL by: "Morad= =A0 El-Hendawy"=0A> [M80elhendawy##yahoo.com]=0A> Hey every body!=0A> Durin= g my perusal to ONIOM pages on Gaussian website, http://www.gaussian.com/g_= tech/g_ur/k_oniom.htm, I=0A> found this statement: =0A> =0A> "For both mini= ma and transition structures, it is usually=0A> more efficient to first opt= imize using mechanical embedding=0A> and then perform a second optimization= with electronic=0A> embedding starting from the resulting structure (rathe= r than=0A> trying to use electronic embedding from the beginning)"=0A> =0A>= I wonder if an expertise body tells us why it is preferred=0A> to start wi= th mechanical embedding then electronic=0A> embedding? Detailed answer with= evidences (i.e. published=0A> papers)is preferred and more appreciated.=0A= > Thanks a mil=0A> Morad El-Hendawy=0A> Ireland=0A> =0A> =0A> =0A> -=3D Thi= s is automatically added to each message by the=0A> mailing script =3D-=0A>= To recover the email address of the author of the message,=0A> please chan= ge=0A> the strange characters on the top line to the -$- sign. You=0A> can al= so=0A=0A> =0A> E-mai= l to subscribers: CHEMISTRY-$-ccl.net=0A> or use:=0A> =A0 =A0 =A0 http://www.= ccl.net/cgi-bin/ccl/send_ccl_message=0A> =0A> E-mail to administrators: CHE= MISTRY-REQUEST-$-ccl.net=0A> or use=0A> =A0 =A0 =A0 http://www.ccl.net/cgi-bi= n/ccl/send_ccl_message=0A> =0A=0A> =A0 =A0 =A0 htt= p://www.ccl.net/chemistry/sub_unsub.shtml=0A> =0A> Before posting, check wa= it time at: http://www.ccl.net=0A> =0A=0A> C= onferences: http://server.ccl.net/chemistry/announcements/conferences/=0A> = =0A=0A= > =0A=0A> =A0 =A0 = =A0=0A> =0A> RTFI: http://www.ccl.net/chemi= stry/aboutccl/instructions/=0A> =0A> =0A>