From chemistry-request@server.ccl.net Fri May 9 10:40:34 2003 Received: from cirse.saclay.cea.fr ([132.166.192.127]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id h49EeYt29249 for ; Fri, 9 May 2003 10:40:34 -0400 Received: from argiope.saclay.cea.fr (argiope.saclay.cea.fr [132.166.192.108]) by cirse.saclay.cea.fr (8.12.9/CEAnet-Internet.1.0) with ESMTP id h49EeYvF025424 for ; Fri, 9 May 2003 16:40:34 +0200 (MEST) Received: from muguet.saclay.cea.fr (unverified) by argiope.saclay.cea.fr (Content Technologies SMTPRS 4.3.6) with ESMTP id for ; Fri, 9 May 2003 16:39:29 +0200 Received: from mirabeau.saclay.cea.fr (mirabeau.saclay.cea.fr [132.166.189.103]) by muguet.saclay.cea.fr (8.12.9/CEAnet-Interne.1.0) with ESMTP id h49EeYF7006272 for ; Fri, 9 May 2003 16:40:34 +0200 (MEST) Received: by mirabeau.saclay.cea.fr with Internet Mail Service (5.5.2653.19) id ; Fri, 9 May 2003 16:33:40 +0200 Message-ID: <3808A7D2DCEAD6118B6300902728726501476A@azurite.saclay.cea.fr> From: VITORGE Pierre 094605 To: chemistry@ccl.net Subject: RE: Gaussian Convergence failure! Date: Fri, 9 May 2003 16:40:29 +0200 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by server.ccl.net id h49EeZt29250 Yes, qc is often needed for such systems (namely S-Fe bonding). One usually starts with a HF calculation and a small basis, then increases the basis using options scf(qc,conver=8), then b3lyp calculation (with the same options) pierre.vitorge@cea.fr -----Message d'origine----- De: zborowsk@chemia.uj.edu.pl [mailto:zborowsk@chemia.uj.edu.pl] Date: vendredi 9 mai 2003 14:35 À: chemistry@ccl.net Objet: CCL:Gaussian Convergence failure! Dear WIlliam I am not sure where your problem is, because you did not attach your input gaussian file with the structure of the molecule. But, if I have a problem with convergence in Gaussian (it is true especially for metal complexes) I usually use the QC option in SCF calculations So, write "SCF=QC" in your input file. Unfortunately you will need more time for your calculations :-( Best regards Kzys > Dear CCLers, > > After several Convergence failure (I changed conformations), what others > I can do for it? My system is about 20 heavy atoms, include one benzal > group in the end, and one Fluorine one Sulfur. After B3LYP/3-21G > optimized, it can not convergence at B3LYP/6-31+G(D) level. Could > anybody give me suggestion. I will summarize the result. Thank you. > > Best > > ------------------------- > William Wei > Faculty of Pharmacy > 19 Russell Street > Toronto, ON. M5S 2S2 > Tel: 1-416-946-8469 > Fax: 1-416-978-8511 > Email: william@phm.utoronto.ca > william.wei@utoronto.ca > Http://phm.utoronto.ca/~william > > Krzysztof Zborowski Faculty of Chemistry Jagiellonian University 3 Ingardena Street 30-060 Krakow, Poland phone: +48(12)632-4888 ext. 2064 or 2067 fax: +48(12)634-05-15 -= This is automatically added to each message by mailing script =- CHEMISTRY@ccl.net -- To Everybody | CHEMISTRY-REQUEST@ccl.net -- To Admins Ftp: ftp.ccl.net | WWW: http://www.ccl.net/chemistry/ | Jan: jkl@ccl.net