From chemistry-request@server.ccl.net Sat Mar 17 01:03:49 2001 Received: from server3.safepages.com ([216.127.146.5]) by server.ccl.net (8.11.0/8.11.0) with ESMTP id f2H63nD30530 for ; Sat, 17 Mar 2001 01:03:49 -0500 Received: from quantumnt (5131-013-230.008.popsite.net [209.69.13.230]) by server3.safepages.com (Postfix) with SMTP id EBB7322F9F for ; Sat, 17 Mar 2001 06:01:50 +0000 (GMT) Message-ID: <001101c0aea7$c267d510$0300a8c0@quantumnt> From: "Jim Kress" To: "CCL" Subject: Universal Force Field Software Date: Sat, 17 Mar 2001 01:01:49 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Anybody know where I can get software (preferably free) that implements the Universal Force Field (for example, A. K. Rappe, C. J. Casewit, K. S. Colwell, W. A. Goddard III, and W. M. Skiff, J. Am. Chem. Soc. 114, 10024-10035 (1992)) ? Thanks. Jim From chemistry-request@server.ccl.net Sat Mar 17 01:06:25 2001 Received: from server3.safepages.com ([216.127.146.5]) by server.ccl.net (8.11.0/8.11.0) with ESMTP id f2H66PD30574 for ; Sat, 17 Mar 2001 01:06:25 -0500 Received: from quantumnt (5131-013-230.008.popsite.net [209.69.13.230]) by server3.safepages.com (Postfix) with SMTP id 3B07F22DCC for ; Sat, 17 Mar 2001 06:04:33 +0000 (GMT) Message-ID: <002d01c0aea8$2310b490$0300a8c0@quantumnt> From: "Jim Kress" To: "CCL" Subject: Universal Force Field Software Date: Sat, 17 Mar 2001 01:04:32 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Anybody know where I can get software (preferably free) that implements the Universal Force Field (for example, A. K. Rappe, C. J. Casewit, K. S. Colwell, W. A. Goddard III, and W. M. Skiff, J. Am. Chem. Soc. 114, 10024-10035 (1992)) ? Thanks. Jim From chemistry-request@server.ccl.net Sat Mar 17 10:31:53 2001 Received: from web12712.mail.yahoo.com ([216.136.174.59]) by server.ccl.net (8.11.0/8.11.0) with SMTP id f2HFVqD00563 for ; Sat, 17 Mar 2001 10:31:53 -0500 Message-ID: <20010317153152.13490.qmail@web12712.mail.yahoo.com> Received: from [65.6.48.45] by web12712.mail.yahoo.com; Sat, 17 Mar 2001 07:31:52 PST Date: Sat, 17 Mar 2001 07:31:52 -0800 (PST) From: water Miller Subject: Re: CCL:experiment of H-bond strength in solution To: mike smith , chemistry@ccl.net In-Reply-To: <20010314202839.82539.qmail@web13202.mail.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Hello everyone, It seems to me that the problem you mentioned should be kind of simple, by just perform accurate free energy calculations in solutions. For example, in order to get the H-bonding strangth of formamide dimer in water, just do two calculations: one free energy for the dimer, and one for the monomer. Without detail results on the surface, you should get an idea about the binding energy of such a H-bond in water(the difference between them)? So the main problem is the free energy calculations, or high accurate solvation model. Presumely, the solute (dimer or monomer for each case) and a few explicit water molecules should be included by QM as the "core", other parts for the system(more water) can be treated by continuum model(reaction field) or MM empirical force field. It seems to me that there are already many results on the free energies of H-bond complexes available, but I don't don't if they have been used to get the H-bond binding energies? Or it is just not so simple? I wish someone could prove or disprove "my" approach with examples. Thanks! Water --- mike smith wrote: > Dear all, > > Since it's well-known that the H-bond strength will > be > highly weaken in solution, compared with that in gap > phase, I am curious if there is any experimental > evidence or hint available. > > Also, I found two papers on the potential enrgy > curves > of H-bond in gas-phase and solution: > (1)Dang, L X; Kollman, P. A, > J Am Chem Soc, 1990, 112,503 > > AT base pair (H-bond & stacking) > from 12kcal/mol(gas) to 0.8kcal/mol > (solution) > > (2)Osapay, K; Young W S; Brooks C L; Case D A > J Phys Chem 1996, 100, 2698 > Updated in Annu Rev Phys Chem, 2000, 51, 129 > > formamide dimer > from 6.7 kcal/mol to 0.8 kcal/mol > > Here, I am wondering if any of you could provide me > more related reference. Also, any discussion on the > method to simulate this accurately would be highly > appreciated. > > Thanks for your attention! > > --Mike > > __________________________________________________ > Do You Yahoo!? > Yahoo! Auctions - Buy the things you want at great > prices. > http://auctions.yahoo.com/ > > > -= This is automatically added to each message by > mailing script =- > CHEMISTRY@ccl.net -- To Everybody | > CHEMISTRY-REQUEST@ccl.net -- To Admins > MAILSERV@ccl.net -- HELP CHEMISTRY or HELP SEARCH > CHEMISTRY-SEARCH@ccl.net -- archive search | > Gopher: gopher.ccl.net 70 > Ftp: ftp.ccl.net | WWW: > http://www.ccl.net/chemistry/ | Jan: jkl@ccl.net > > > > > __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ From chemistry-request@server.ccl.net Sat Mar 17 18:28:19 2001 Received: from lua.ifi.unicamp.br ([143.106.6.13]) by server.ccl.net (8.11.0/8.11.0) with ESMTP id f2HNSID02013 for ; Sat, 17 Mar 2001 18:28:18 -0500 Received: by lua.ifi.unicamp.br (Postfix, from userid 106) id 38D6EA91B; Sat, 17 Mar 2001 20:25:18 -0300 (BSC) Received: from ifi.unicamp.br (localhost [127.0.0.1]) by lua.ifi.unicamp.br (Postfix) with SMTP id E540D5515 for ; Sat, 17 Mar 2001 20:25:16 -0300 (BSC) Date: Sat, 17 Mar 2001 20:25:16 -0300 (BSC) To: Subject: DFT: COSMO vs G98 From: X-Mailer: TWIG 2.6.2 X-Client-IP: 128.196.86.125 Message-Id: <20010317232516.E540D5515@lua.ifi.unicamp.br> X-AntiVirus: scanned for viruses by AMaViS 0.2.1 (http://amavis.org/) Dear CCL'ers, I'm trying to reproduce some DFT calculations carried out with the DZP basis using the local density approximation (LDA) implemented in DMOL (MSI/Biosym, Inc). There is no additional information about the DFT method or functional used. I don't have access to such program and so I want to know if with those informations I can choose in G98 a functional and a basis set in order to reproduce those calculations. Can anybody help me with this? Thanks in advance, Demetrio Filho From chemistry-request@server.ccl.net Sat Mar 17 20:34:06 2001 Received: from keeper.ludwig.edu.au ([128.250.250.99]) by server.ccl.net (8.11.0/8.11.0) with ESMTP id f2I1Y3D03424 for ; Sat, 17 Mar 2001 20:34:05 -0500 Received: by keeper.ludwig.edu.au with Internet Mail Service (5.5.2653.19) id ; Sun, 18 Mar 2001 12:33:57 +1100 Message-ID: <805AD25D3702D311805900062B004E42BD0986@keeper.ludwig.edu.au> From: Robert Jorissen To: "'chemistry@ccl.net'" Subject: Re: MOPAC software - free versions for Windows Date: Sun, 18 Mar 2001 12:33:56 +1100 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain There are at least two versions of MOPAC 7 which have user interfaces. Winmopac7.21 from Roman Shchepin and Dmitriy Litvinov uses the publicly available programs MOPAC 7, the Rasmol molecular visualization program and the molecular coordinate format conversion program Babel and puts them together in a PC interface. You have to type in the Z-matrix but quick visualization using Rasmol greatly helps. The relevant Web pages are http://members.fortunecity.com/winmopac/ and http://winmopac.narod.ru/english.html. This program is free. The program Mopd from Peter Zhou also visualizes the molecules in MOPAC files. This program, as well as a compiled version of MOPAC 7 (for 60 heavy atoms and 60 hydrogens), can be downloaded at no cost from http://www.geocities.com/peterxz/. These programs require Windows 95 or Windows NT. Robert Jorissen Ludwig Insitute for Cancer Research, Melbourne branch