From chemistry-request@ccl.net Fri Jul 2 09:06:42 2004 Received: from mx4.trentu.ca (mx4.trentu.ca [192.75.12.5]) by server.ccl.net (8.12.8/8.12.8) with SMTP id i62E6eFY028667 for ; Fri, 2 Jul 2004 09:06:41 -0500 Received: (qmail 10619 invoked by uid 510); 2 Jul 2004 14:12:00 -0000 Received: from elewars!at!trentu.cA by mx4.trentu.ca by uid 501 with qmail-scanner-1.20rc3 (f-prot: 4.4.1/3.14.11. spamassassin: 2.62. Clear:RC:1:. Processed in 0.019618 secs); 02 Jul 2004 14:12:00 -0000 Received: from unknown (HELO trentu.cA) (209.42.102.47) by mx4.trentu.ca with SMTP; 2 Jul 2004 14:12:00 -0000 Message-ID: <40E56E3F.10400!at!trentu.cA> Date: Fri, 02 Jul 2004 10:16:31 -0400 From: Errol Lewars User-Agent: Mozilla/5.0 (Windows; U; WinNT4.0; en-US; rv:1.6) Gecko/20040113 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Yan Zhao , chemistry!at!ccl.net Subject: Re: CCL:gaussian03 optimization to transition state References: <200407012308.i61N818h020314!at!trojan.software.umn.edu> In-Reply-To: <200407012308.i61N818h020314!at!trojan.software.umn.edu> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, hits=0.0 required=7.5 tests=none autolearn=no version=2.61 X-Spam-Checker-Version: SpamAssassin 2.61 (1.212.2.1-2003-12-09-exp) on servernd.ccl.net 2004 July 2 People new to gaussian may wish to note that Gaussian *never* seems to find a transition state unless the NoEigentest (see below) keyword is included. I don't know why this is not the default. A good option is often Opt(TS, NoEigenTest, mndofc, MaxCycle=99). EL ===== Yan Zhao wrote: >Substitute "POpt=(Saddle=1)" for "opt=(ts,noeigentest,maxcycle=100)", then >it will not stop because the wrong number of Negaative eigenvalues, if the >optimization does not converge, you probably should try some better initial >guesses of the geometry or add "calcfc" in the opt keyword. > >Yan > >On 1 Jul 2004, Carsten Detering wrote: > > >>Hi all, >> >> I would like to optimize a complex involving a bifurcated hydrogen >>bond between three nitrogen atoms (trimethylamine and triazen) to a >>saddle point (which I know exists from previous Mopac calculations). >>Taking this header line in the input file >> >>B3LYP/6-31g* POpt=(Saddle=1) nosymmetry test >> >>the optimization finishes with an error >> >>optimization stopped >> --wrong number of Negative eigenvalues: Desired= 1 Actual= 2 >> --Flag reset to prevent archiving >> >>Then I get, at the bottom, the typical proverb that you see only when a >>calculation has successfully finished, and then >> >>Could anybody make some suggestions how to fix this? >> >>Thanks a lot in advance, >> >>Carsten >> >> >>To send e-mail to subscribers of CCL put the string CCL: on your Subject: >>line >> >>Send your subscription/unsubscription requests to: >> >> >CHEMISTRY-REQUEST!at!ccl.net > > >> >> >> >> >> >> >> >*************************************** >Yan Zhao yzhao!at!chem.umn.edu >Smith Hall 232 (612)-625-5311 >Department of Chemistry >University of Minnesota >207 Pleasant St SE >Minneapolis, MN 55455 >*************************************** > > > >-= This is automatically added to each message by the mailing script =- >To send e-mail to subscribers of CCL put the string CCL: on your Subject: line >and send your message to: CHEMISTRY!at!ccl.net > >Send your subscription/unsubscription requests to: CHEMISTRY-REQUEST!at!ccl.net >HOME Page: http://www.ccl.net | Jobs Page: http://www.ccl.net/jobs > >If your mail is bouncing from CCL.NET domain send it to the maintainer: >Jan Labanowski, jlabanow!at!nd.edu (read about it on CCL Home Page) >-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > > > > > >