From chemistry-request /at\ccl.net Mon Nov 3 06:27:41 2003 Received: from mail.uvigo.es (mail.uvigo.es [193.146.32.91]) by server.ccl.net (8.12.8/8.12.8) with ESMTP id hA3BR8hP008339 for >ccl.net>; Mon, 3 Nov 2003 06:27:09 -0500 Received: from mail.uvigo.es (localhost [127.0.0.1]) by mail.uvigo.es (8.12.9/8.12.1) with ESMTP id hA3BR7ck009117 for >ccl.net>; Mon, 3 Nov 2003 12:27:07 +0100 Received: from correo.uvigo.es (correo.uvigo.es [193.146.32.68]) by mail.uvigo.es (8.12.9/8.12.1) with ESMTP id hA3BR6uA009103 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NOT) for >ccl.net>; Mon, 3 Nov 2003 12:27:06 +0100 Received: from correo (correo [193.146.32.68]) by correo.uvigo.es (8.12.9/8.12.5) with ESMTP id hA3BR6Qk017438 for >ccl.net>; Mon, 3 Nov 2003 12:27:06 +0100 Date: Mon, 3 Nov 2003 12:27:06 +0100 (CET) From: Carlos Silva Lopez >uvigo.es> X-X-Sender: To: >ccl.net> Subject: Fractional Occupation Numbers Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 X-Spam-Status: No, hits=0.0 required=7.0 tests=USER_AGENT_PINE version=2.55 X-Spam-Checker-Version: SpamAssassin 2.55 (1.174.2.19-2003-05-19-exp) Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from QUOTED-PRINTABLE to 8bit by server.ccl.net id hA3BRfhP008360 Hello CCLers Thanks for these first suggestions, I think I should clarify my question since it seems it has led to some misunderstandings. I came across with a few papers from Goddard and Orlova such as: JChemPhys v111 n17 p7705 1999 JChemPhys v112 n23 p10085 2000 They use g98 and several functionals with partial occupation numbers to study concerted reactions and they report really nice results compared with MCSCF methods. I would like to use this approach but I don not find any documentation for g98. Someone suggested to try a fractional total charge for the system, this is not what I ment to do. Furthermore, gaussian will crash because the code is expecting an integer for that value, not a floating point. Thanks for your feedback _-_-_-_-_-_-_-_-_-_-_-_- Carlos Silva Lspez Dept. Qummica Organica Universidade de Vigo Phone:0034 986812226 -_-_-_-_-_-_-_-_-_-_-_-_