From zuilhof@Sg1.OC.WAU.NL Fri Jan 9 03:13:53 1998 Received: from net.wau.nl for zuilhof@Sg1.OC.WAU.NL by www.ccl.net (8.8.3/950822.1) id CAA03388; Fri, 9 Jan 1998 02:24:39 -0500 (EST) Received: from SG1.OC.WAU.NL by NET.WAU.NL (PMDF V5.1-9 #23446) with SMTP id <01IS605E62N0006NC4@NET.WAU.NL> for CHEMISTRY@www.ccl.net; Fri, 9 Jan 1998 08:25:29 GMT +0100 Received: from [137.224.136.38] by SG1.OC.WAU.NL via SMTP (931110.SGI/930416.SGI) for @Net.WAU.NL:CHEMISTRY@www.ccl.net id AA02431; Fri, 09 Jan 1998 08:24:38 +0100 Date: Fri, 09 Jan 1998 08:24:38 +0100 From: zuilhof@Sg1.OC.WAU.NL (Han Zuilhof) Subject: Re: CCL:question on irc To: Armando Juan Navarro Vazquez , CHEMISTRY@www.ccl.net Message-id: MIME-version: 1.0 Content-type: text/plain; charset="us-ascii" At 8:29 PM 1/8/98, Armando Juan Navarro Vazquez wrote: >Dear netters: >I have tried to perform a irc calculation on a system with a very flat >potential surface, but it could be only completed sucessfully on one side >of the potential, but only one point is located in the other side (program >considers is as a minimum). How can I calculate further points on this >side of the potential?. >Thanks in advance > Armando Navarro > Departamento de quimica Organica. Facultade de quimica. Universidade de > Santiago de Compostela. > e-mail:qoajnv@uscmail.usc.es > Dear Armando, Try bigger step size. This often helps to find points on the reaction coordinate which are indeed lower in energy than the TS; once you're going downhill, further IRC following becomes easier. I've bumbed into this situations myself several times, and this was the solution to at least my problems. Don't make the stepsize TOO big, as this might mean that you lose track of the IRC, and start to wander about on the potential energy surface. Finally, several questions and answers on problems with IRC are available in the CCL archives, which -with the new web search engine- is a really easy to use tool. Best regards, Han ______________________________________________________________________ Han Zuilhof | E-mail: ZUILHOF@SG1.OC.WAU.NL Laboratory of Organic Chemistry | FAX : 31-317-484914 Department of Biomolecular Sciences | phone : 31-317-482367 Wageningen Agricultural University | Dreijenplein 8 | 6703 HB Wageningen | "Excite a photochemist!" The Netherlands | From eloranta@voimax.voima.jkl.fi Fri Jan 9 05:13:53 1998 Received: from voimax.voima.jkl.fi for eloranta@voimax.voima.jkl.fi by www.ccl.net (8.8.3/950822.1) id EAA04395; Fri, 9 Jan 1998 04:48:53 -0500 (EST) Received: (from eloranta@localhost) by voimax.voima.jkl.fi (8.8.7/8.8.7) id LAA08113 for chemistry@www.ccl.net; Fri, 9 Jan 1998 11:47:56 +0200 From: Jussi Eloranta Message-Id: <199801090947.LAA08113@voimax.voima.jkl.fi> Subject: calculation of hyperfine coupling constants using molpro? To: chemistry@www.ccl.net Date: Fri, 9 Jan 1998 11:47:55 +0200 (EET) Content-Type: text Dear Netters, Does anyone know how to calculate isotropic (and possibly anisotropic) hyperfine coupling constants for radical molecules using MOLPRO? I have tried to look at the populations analysis module but have not found anything concerning spin densities. Thanks, Jussi Eloranta (eloranta@jyu.fi) From N.Goldberg@tu-bs.de Fri Jan 9 06:13:59 1998 Received: from rzcomm1.rz.tu-bs.de for N.Goldberg@tu-bs.de by www.ccl.net (8.8.3/950822.1) id FAA04567; Fri, 9 Jan 1998 05:51:52 -0500 (EST) Received: from tu-bs.de (bonding.org-chem.nat.tu-bs.de [134.169.19.161]) by rzcomm1.rz.tu-bs.de (8.8.6/8.8.6) with ESMTP id LAA07823 for ; Fri, 9 Jan 1998 11:51:22 +0100 (MET) Message-ID: <34B6027E.BE5D9C36@tu-bs.de> Date: Fri, 09 Jan 1998 11:57:03 +0100 From: Norman Goldberg Organization: TU-Braunschweig X-Mailer: Mozilla 4.03 [de] (Win95; I) MIME-Version: 1.0 To: Computational Chemistry Subject: hardware-dependent CCSD results Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Hi, I've been getting some strange results and was wondering if anybody out there has experienced s.th. similar - has an explanation: I ran CCSD(T)/6-31G* single point calculations (preoptimized at the B3LYP/6-311G** level) of several small unsaturated hydrocarbons on an SGI O2/R10000 (IRIX6.3/32 bit) and a SGI PowerChallenge (IRIX 6.2/64 bit) (identical Gaussian94 revisions on the machines). The results I get up to the MP4SDQ level are identical, but the CCSD and CCSD(T) results strongly depend on the hardware used. The CCSD(T) values I obtain on the O2 are always 8 +- 0.1 kcal/mol higher than the values from the 64 bit machine! Is this simply a numerical problem and/or is there a way around it? Greetings, Norman -- ______________________________________ Dr. Norman Goldberg (N.Goldberg@tu-bs.de) Technische Universitaet Braunschweig Institut fuer Organische Chemie Hagenring 30 D-38106 Braunschweig (FRG) Tel.: +(0)531-391-5312 Fax : +(0)531-391-5388 ______________________________________ From XIENING@MEENA.CC.UREGINA.CA Fri Jan 9 12:13:58 1998 Received: from veena.cc.uregina.ca for XIENING@MEENA.CC.UREGINA.CA by www.ccl.net (8.8.3/950822.1) id LAA06209; Fri, 9 Jan 1998 11:26:27 -0500 (EST) Received: from meena.cc.uregina.ca by meena.cc.uregina.ca (PMDF V5.1-9 #27364) id <01IS6433DO1IBESZ4U@meena.cc.uregina.ca> for chemistry@www.ccl.net; Fri, 9 Jan 1998 10:26:23 CST Date: Fri, 09 Jan 1998 10:26:22 -0600 (CST) From: "XIE, NING" Subject: molecule-drawing software ? To: chemistry@www.ccl.net Message-id: <01IS6433DO1KBESZ4U@meena.cc.uregina.ca> X-VMS-To: IN%"chemistry@www.ccl.net" MIME-version: 1.0 Content-type: TEXT/PLAIN; CHARSET=US-ASCII Hi, again, I'm wondering if anybody can tell me where I can find a free or shareware for molecule-drawing so that I can draw a molecule and save it as pdb file that can then be opened in Gaussian? I am currently using hyperchem for this purpose. I'm going to move to another institute where only Gaussian is available. It is too difficult to write z-matrix files by yourself for large molecules. Any suggestion is welcome and thank you for your help. ning From XIENING@MEENA.CC.UREGINA.CA Fri Jan 9 12:36:28 1998 Received: from veena.cc.uregina.ca for XIENING@MEENA.CC.UREGINA.CA by www.ccl.net (8.8.3/950822.1) id LAA06176; Fri, 9 Jan 1998 11:18:07 -0500 (EST) Received: from meena.cc.uregina.ca by meena.cc.uregina.ca (PMDF V5.1-9 #27364) id <01IS63LJ05VKBESZ4U@meena.cc.uregina.ca> for chemistry@www.ccl.net; Fri, 9 Jan 1998 10:18:00 CST Date: Fri, 09 Jan 1998 10:17:59 -0600 (CST) From: "XIE, NING" Subject: entropy & HOMO/LUMO energy To: chemistry@www.ccl.net Message-id: <01IS63LJ7EAQBESZ4U@meena.cc.uregina.ca> X-VMS-To: IN%"chemistry@www.ccl.net" MIME-version: 1.0 Content-type: TEXT/PLAIN; CHARSET=US-ASCII Hi, there, Good day! I'm using Gaussian to calculate HOMO/LUMO energies of some sulfur- containing compounds. When a molecule is optimized, we can get the heat of formation because the entropy effect is not taken into consideration. Here is my question: Is the HOMO/LUMO energy calculated this way related to entropy? In another word, does it matter with the value of HOMO/LUMO energy if the entropy effect is taken into consideration or not? If they are related, what should I do to include the entropy effect? Thank you for your time. ning From mem2!mem2.ilc.msu.su!mal@gw.ilc.msu.su Fri Jan 9 14:13:56 1998 Received: from gw.ilc.msu.su for mem2!mem2.ilc.msu.su!mal@gw.ilc.msu.su by www.ccl.net (8.8.3/950822.1) id NAA07051; Fri, 9 Jan 1998 13:59:27 -0500 (EST) Received: from mem2.UUCP (uumem2@localhost) by gw.ilc.msu.su (8.6.12/8.6.12) with UUCP id WAA17606 for chemistry@www.ccl.net; Fri, 9 Jan 1998 22:00:59 GMT Received: by mem2.ilc.msu.su (dMail for Windows v1.2P, 23Jul96); Fri, 9 Jan 1998 21:55:43 +0300 To: chemistry@www.ccl.net Organization: ILC MSU Message-Id: From: mal@mem2.ilc.msu.su (Dmitriy Malakhov) Date: Fri, 9 Jan 1998 21:55:43 +0300 (MSK) X-Mailer: dMail [Demos Mail for Windows v1.2 Professional] Return-Receipt-To: mal@mem2.ilc.msu.su Subject: MOPACK calculation Lines: 18 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Dear Chemists! I am newcomer in computation chemistry. I wish to calculate the structure of molecule in AM1 forcefield (simple geometry optimization) with some constrains. As I know these constraints can be done on internal coordinates by MOPACK program, but I need to constrain some angles and distances which are not internal coordinates. Is it possible to restrain not only internal coordinates in MOPACK or I have to choose internal coordinate properly? Thank you for answer! Best regards Phd. St. DmitryMalakhov Moscow State University, Moscow, Russia E-mail: mal@mem2.ilc.msu.su or malakhoff@hotmail.com From bruno@antas.agraria.uniss.it Fri Jan 9 18:14:00 1998 Received: from cinymp.cineca.it for bruno@antas.agraria.uniss.it by www.ccl.net (8.8.3/950822.1) id RAA08106; Fri, 9 Jan 1998 17:15:59 -0500 (EST) Received: from antas.agraria.uniss.it by cinymp.cineca.it (5.61/UNICOS-PP) id AA78321; Fri, 9 Jan 98 22:15:17 GMT Date: Fri, 9 Jan 1998 23:12:40 +0100 (NFT) From: "Dr. Bruno Manunza" To: "XIE, NING" Cc: chemistry@www.ccl.net Subject: Re: CCL:G:molecule-drawing software ? In-Reply-To: <01IS6433DO1KBESZ4U@meena.cc.uregina.ca> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII On Fri, 9 Jan 1998, XIE, NING wrote: > Hi, again, > I'm wondering if anybody can tell me where I can find a free or > shareware for molecule-drawing so that I can draw a molecule and > save it as pdb file that can then be opened in Gaussian? I am > currently using hyperchem for this purpose. I'm going to move to > another institute where only Gaussian is available. It is too > difficult to write z-matrix files by yourself for large molecules. > Any suggestion is welcome and thank you for your help. > ning > Dear Ning, you may try molgen for MSDOS it's free at: ftp://www.ccl.net/pub/chemistry/software/MS-DOS/molgen/ Hope it helps bye Bruno Dr Bruno Manunza DISAABA (Dept. of Agricultural Environm. Sci) University of Sassari V.le Italia 39 07100 Sassari, ITALY phone: 39 79 229215 fax: 39 79 229276 e-mail: bruno@antas.agraria.uniss.it e-mail: bruno@tharros.dipchim.uniss.it e-mail: gx6bot81@cray.cineca.it web: http://antas.agraria.uniss.it From editor@mactech.com Fri Jan 9 20:14:01 1998 Received: from neon.chem.ucla.edu for editor@mactech.com by www.ccl.net (8.8.3/950822.1) id TAA08508; Fri, 9 Jan 1998 19:16:16 -0500 (EST) Received: from [128.97.76.42] ([128.97.76.42]) by neon.chem.ucla.edu (8.8.0/8.8.0) with ESMTP id QAA13852 for ; Fri, 9 Jan 1998 16:18:44 -0800 (PST) X-Sender: nick@128.97.35.251 Message-Id: In-Reply-To: <01IS6433DO1KBESZ4U@meena.cc.uregina.ca> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Fri, 9 Jan 1998 16:20:40 -0700 To: chemistry@www.ccl.net From: Nick DeMello Subject: Re: CCL:G:molecule-drawing software ? It's not freeware/shareware, but I find the commercial product "Chem3D" from CamSoft is an excellant tool for this job. Basically, it's a swiss army knife for computational chemists--very flexible with a wealth of molecular structure reading, visualizing, manipulating, and saving tools. Hope this helps, ______________ >I'm wondering if anybody can tell me where I can find a free or >shareware for molecule-drawing so that I can draw a molecule and >save it as pdb file that can then be opened in Gaussian? I am >currently using hyperchem for this purpose. I'm going to move to >another institute where only Gaussian is available. It is too >difficult to write z-matrix files by yourself for large molecules. >Any suggestion is welcome and thank you for your help. >ning ____Nicholas C. DeMello, Ph.D.________________________________________ Editor of MacTech Magazine, for Mac OS Developers and Programmers http://www.MacTech.com/ _/ _/ _/ _/_/_/ _/ _/ Chemistry: nick@chem.ucla.edu _/_/ _/ _/ _/ _/ _/_/_/ MacTech: editor@MacTech.com _/ _/_/ _/ _/ _/ _/ http://www.chem.ucla.edu/~nick/ _/ _/ _/_/_/ _/ _/