From chemistry-request@server.ccl.net Sun Aug 19 22:18:10 2001 Received: from power.curtin.edu.au ([134.7.118.91]) by server.ccl.net (8.11.0/8.11.0) with ESMTP id f7K2I8M22048 for ; Sun, 19 Aug 2001 22:18:09 -0400 Received: from [10.0.1.49] ([134.7.118.25]) by power.curtin.edu.au (8.10.2/8.10.2/SuSE Linux 8.10.0-0.3) with ESMTP id f7K2HtF21921; Mon, 20 Aug 2001 10:17:56 +0800 X-Authentication-Warning: power.curtin.edu.au: Host [134.7.118.25] claimed to be [10.0.1.49] Mime-Version: 1.0 Message-Id: In-Reply-To: <15228.64389.348325.335076@gargle.gargle.HOWL> References: <15228.64389.348325.335076@gargle.gargle.HOWL> Date: Mon, 20 Aug 2001 10:18:26 +0800 To: Keith Refson , CHEMISTRY@ccl.net From: Andrew Rohl Subject: Re: CCL:SUMMARY: Potential parameter fitting Content-Type: text/plain; charset="us-ascii" ; format="flowed" >2. A number of respondents pointed me to GULP by Julian Gale > http://www.ch.ic.ac.uk/gale/Research/gulp.html > which is slightly embarrassing since I thought I knew that program > fairly well :) It can indeed be used to fit to an energy hypersurface > (which I erroneously thought it wasn't well suited for). > > GULP uses a 3D periodic model, which isn't what I need for this > particular calculation, (A simple isolated moecular cluster), but > of course it's not to hard to achieve this by judicious use of a > large supercell and interaction cutoffs and turning off the > long-ranged part of coulomb interactions. Might I respectfully suggest that Keith take yet another look at the gulp manual :-). GULP handles 3-D and 0-D cases (with 2-D coming real soon now). So to do a molecular calculation just don't define a cell. I also believe that GULP is the superior tool for the fitting of hypersurfaces as I suspect that its range of potential types is unsurpassed... -- ------------------------------------------------------------------------------ Andrew Rohl Email: andrew@power.curtin.edu.au Senior Lecturer in Computational Chemistry Department of Applied Chemistry Phone: +61 8 9266 7317 (Office) Curtin University of Technology +61 8 9266 3780 (Lab) PO Box U 1987 Perth, 6845 FAX: +61 8 9266 2300 WESTERN AUSTRALIA WWW: http://chemistry.curtin.edu.au/staff/alr ------------------------------------------------------------------------------