From chemistry-request@ccl.net Mon Mar 15 09:43:59 2004 Received: from caravelle.univ-lemans.fr (caravelle.univ-lemans.fr [195.221.244.4]) by server.ccl.net (8.12.8/8.12.8) with ESMTP id i2FEhwjs011935 for ; Mon, 15 Mar 2004 09:43:58 -0500 Received: from [193.52.30.144] (pascalgo-crihan.univ-lemans.fr [193.52.30.144]) by caravelle.univ-lemans.fr (8.12.10/8.12.10/(CeTIC - 18/09/03)) with ESMTP id i2FEjpR8022377 for ; Mon, 15 Mar 2004 15:45:59 +0100 (MET) Mime-Version: 1.0 (Apple Message framework v612) Message-Id: <565DAEDE-768F-11D8-A730-0003934391AA.-at-.univ-lemans.fr> Content-Type: text/plain; charset=ISO-8859-1; format=flowed To: chemistry.-at-.ccl.net From: Pascal Gosselin Subject: Spin Density vs SOMO surfaces Date: Mon, 15 Mar 2004 15:45:00 +0100 X-Mailer: Apple Mail (2.612) X-Spam-Status: No, hits=0.0 required=7.0 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 Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by server.ccl.net id i2FEhxjs011939 Dear all, I wanted to visualize the localization of the unpaired electron in radical-cations whose structures were optimized at the UB3LYP/6-31G* level in Gaussian98. For that purpose, I asked Gaussview to compute both Spin Density and SOMO surfaces. In most cases, both pictures were very similar. However, in some cases, I was surprised to observe two very different pictures, i.e. the surfaces were located over completely different regions of the radical-cation. In some cases, alphaSomo, alphaSomo-1 and betaSomo were found very close in energy. I tried to obtain a "mean view" of the system by adding the alphaSomo and alphaSomo-1 then subtracting betaSomo (with the cubman utility within g98 package). The resulting picture remained different of the Spin Density surface. Has somebody an explanation? All the Best ********************************************** Dr Pascal Gosselin Laboratoire de Synthhse Organique/UMR-CNRS-6011 Faculti des Sciences & Techniques Universiti du Maine Avenue Olivier Messiaen F-72085 Le Mans Cedex 9 France Tel: + 33 (0)2 43 83 33 71 Fax: + 33 (0)2 43 83 39 02 Email: Pascal.Gosselin.-at-.univ-lemans.fr ********************************************** Soutenez le mouvement SAUVONS LA RECHERCHE : http://recherche-en-danger.apinc.org/ **********************************************