From owner-chemistry /at\ccl.net Fri Dec 14 06:55:00 2007 From: "Andreas Klamt klamt^cosmologic.de" To: CCL Subject: CCL: solvent models in MOPAC Message-Id: <-35850-071214064921-31825-10fdlFQ+i4b0B7bW1+QFKQ(~)server.ccl.net> X-Original-From: Andreas Klamt Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=ISO-8859-1; format=flowed Date: Fri, 14 Dec 2007 12:49:07 +0100 MIME-Version: 1.0 Sent to CCL by: Andreas Klamt [klamt**cosmologic.de] Dear Andras, I am not absolutely sure, which kind of improvement you are looking for. = We at COSMOlogic are doing our conformational searches for low-energy=20 conformations in gas-phase and solution since long based on AM1-gasphase = and AM1/COSMO in a locally modified version of MOPAC7. Altogether we do=20 it in a sophisitcated procedure called COSMOconf , involving an initial = molecular perception for relevant flexible bonds, potential=20 intramolecular H-bonds, ... followed by multiple AM1/MOPAC runs with=20 constraints (which are enabled in our version) and subsequent=20 constraint-released optimizations, geometry clustering, AM1/COSMO runs=20 for the lowest energy cluster representatives, and final selection of=20 the lowest energy gasphase and COSMO conformations. On top of that,=20 COSMOconf can further reduce the conformations by sigma profile=20 similarity, it can submit DFT/COSMO jobs for the low-lying MOPAC=20 conformations, and several things more. We have just released COSMOconf as a product. For a test installation=20 please contact us. Andreas andras.borosy_-_givaudan.com schrieb: > > Dear Colleagues, > > Might conformer generation be improved (both HF and geometry) in=20 > MOPAC by adding a solvent model like Tomasi: > > http://cc-ipcp.icp.ac.ru/mopac93.pdf > > Or anything else? > > Regards, > > Dr. Andr=E1s P=E9ter Borosy > Scientific Modelling Expert > Fragrance Research > Givaudan Schweiz AG - Ueberlandstrasse 138 - CH-8600 - D=FCbendor= f=20 > - Switzerland > T:+41-44-824 2164 - F:+41-44-8242926 - http://www.givaudan.com=20 --=20 -------------------------------------------------------------------------= ---- Dr. habil. Andreas Klamt COSMOlogic GmbH&CoKG Burscheider Str. 515 51381 Leverkusen, Germany Tel.: +49-2171-73168-1 Fax: +49-2171-73168-9 e-mail: klamt|-|cosmologic.de web: www.cosmologic.de -------------------------------------------------------------------------= ---- COSMOlogic Your Competent Partner for Computational Chemistry and Fluid Thermodynamics -------------------------------------------------------------------------= ----