From owner-chemistry # - at - # ccl.net Thu Jun 10 14:39:00 2010 From: "Ol Ga eurisco1(0)pochta.ru" To: CCL Subject: CCL:G: PBC with gaussian Message-Id: <-42091-100610133953-15856-+vKDG2PZIwCkiMEd8kjubA^-^server.ccl.net> X-Original-From: "Ol Ga" Date: Thu, 10 Jun 2010 13:39:52 -0400 Sent to CCL by: "Ol Ga" [eurisco1-x-pochta.ru] Dear Upakarasamy Lourderaj, You can study periodic adsorption - optimize structures and find TS with QST2 (QST3) methods. Also You can study adsorption on a cluster (a molecular approach), I.e. without PBC conditions. An example for PBC calculations (one from gaussian example files) : #p lsda/sto-3g force geom=modred pbc=gammaonly 2d PBC, also test for addredundant with PBC C(H)NC(CN)C(H) - chain (C-N-C-N- core) 0,1 B 0.7260460000 -0.6287740000 0.0000000000 N -0.7260460000 -0.6287740000 0.0000000000 N 1.4520920000 0.6287740000 0.0000000000 B -1.4520920000 0.6287740000 0.0000000000 B 0.7260460000 1.8863230000 0.0000000000 N -0.7260460000 1.8863230000 0.0000000000 N 1.4520920000 3.1438710000 0.0000000000 B -1.4520920000 3.1438710000 0.0000000000 Tv 4.3562760000 0.0000000000 0.0000000000 Tv 0.0000000000 5.0301940000 0.0000000000 11 1 21 F * * * F * * * * F If you are planning to study adsorption on a metallic surface, I think it will be really difficult with Gaussian. Sincerely, Ol Ga PS: Possible you will need to play with IOPs to reduce time of calculations. -------------------------------------------------- > From: "Upakarasamy Lourderaj u.lourderaj^-^gmail.com" Sent: Thursday, June 10, 2010 4:01 PM To: "Ga, Ol " Subject: CCL:G: PBC with gaussian > > > Sent to CCL by: "Upakarasamy Lourderaj" [u.lourderaj!^!gmail.com] > I am studying interaction of organic molecules on surfaces. I would appreciate very much if you let me guide through as to how to give input for such calculations. I want to use periodic boundary condition(PBC) for the surface only, while the organic molecule should treated as a single molecule. Can we do such calculations using g03? > >