From wsmith@sunstat1.exphysik.uni-leipzig.de Sat Jun 6 06:22:21 1998 Received: from hpkom22.mpgag.uni-leipzig.de (hpkom22.mpgag.uni-leipzig.de [139.18.81.1]) by www.ccl.net (8.8.3/8.8.6/OSC/CCL 1.0) with SMTP id GAA16979 Sat, 6 Jun 1998 06:22:16 -0400 (EDT) Received: from sunstat1.exphysik.uni-leipzig.de by hpkom22.mpgag.uni-leipzig.de with SMTP (1.38.193.4/15.6) id AA18444; Sat, 6 Jun 1998 12:22:05 +0200 Received: from localhost by sunstat1.exphysik.uni-leipzig.de (4.1/SMI-4.1) id AA08598; Sat, 6 Jun 98 12:20:55 +0200 Date: Sat, 6 Jun 1998 12:20:54 +0200 (MET DST) From: "William R. Smith" X-Sender: wsmith@sunstat1 To: chemistry@www.ccl.net Subject: Educational Web Site Announcement Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Hello, The following may be of interest to members of this list. We invite you to visit a new educational web site located at http://www.chemical-stoichiometry.net It contains: 1. a tutorial on the topic of "chemical reaction stoichiometry"; the tutorial also describes a simple computational method that uses only basic knowledge concerning solving sets of linear algebraic equations. 2. an interactive Java Applet that will balance any single chemical reaction, or find a complete set of chemical equations for any specified chemical system. 3. pointers to related software. 4. a list of literature sources of papers on the subject. The site is intended to be a resource for students, instructors, and practioners. We welcome feedback and suggestions for improvement, especially concerning points 3 and 4 above. Best Regards, W. R. Smith From Krys.Radacki@ac.rwth-aachen.de Sat Jun 6 14:54:35 1998 Received: from mail.rwth-aachen.de (mail.RWTH-Aachen.DE [137.226.144.9]) by www.ccl.net (8.8.3/8.8.6/OSC/CCL 1.0) with ESMTP id OAA17794 Sat, 6 Jun 1998 14:54:34 -0400 (EDT) Received: from Zosia (zosia.dorf.RWTH-Aachen.DE) by mail.rwth-aachen.de (PMDF V5.1-10 #30440) with SMTP id <01IXXHGI3WWA000A4K@mail.rwth-aachen.de> for chemistry@www.ccl.net; Sat, 6 Jun 1998 20:55:34 +0200 Date: Sat, 06 Jun 1998 20:54:28 +0200 From: Krzysztof Radacki Subject: G:Sn2-reaction X-Sender: kradacki@mail.rwth-aachen.de To: chemistry@www.ccl.net Message-id: <3.0.3.32.19980606205428.006a4dec@mail.rwth-aachen.de> MIME-version: 1.0 X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.3 (32) Content-type: text/plain; charset="us-ascii" Hi CCL'ers. I'm trying to calculate TS for one Sn2 reaction. As starting point I used A-B..C where A-B was optimised as adduct and C as pure substance. As I know product is A..B-C (known from molecular dynamics in best chemical computer called "Schlenk-flask with periodic-box 25 ml filled with n-pentan molecules, run time 5 min"). I've tried to change primary distance B...C but what I'm becoming is A-B..C with very big B..C distance or if B..C was short A..B-C with veeeery long A..B distance. What I've tried was three jobs: 1. opt=(z-matrix,TS) answer: -- Wrong number of Negative eigenvalues: Desired= 1 Actual= 0 2. opt=(z-matrix,Saddle=2) answer: -- Wrong number of Negative eigenvalues: Desired= 2 Actual= 0 3. opt=(z-matrix) answer: after useing all possible steps how I wrote above one of two A..B or B..C distances going in direction infinity Maximum Force 0.000143 0.000450 YES RMS Force 0.000076 0.000300 YES Maximum Displacement 0.248104 0.001800 NO RMS Displacement 0.044904 0.001200 NO Can somebody tell me how to make Gaussian to do it? thanks in advance Krzys Radacki _________________________---------------------------------------------------- ------------------------- e-mail: Krys.Radacki@ac.RWTH-Aachen.DE --- ---------------------------------------------------------------------------- -