From ccl@www.ccl.net Wed May 7 03:41:36 1997 Received: from bedrock.ccl.net for ccl@www.ccl.net by www.ccl.net (8.8.3/950822.1) id CAA18376; Wed, 7 May 1997 02:59:17 -0400 (EDT) Received: from f6.hotmail.com for vores@hotmail.com by bedrock.ccl.net (8.8.3/950822.1) id CAA09938; Wed, 7 May 1997 02:59:15 -0400 (EDT) Received: (from root@localhost) by f6.hotmail.com (8.7.5/8.7.3) id XAA13258; Tue, 6 May 1997 23:58:46 -0700 (PDT) Message-Id: <199705070658.XAA13258@f6.hotmail.com> Received: from 158.250.32.157 by www.hotmail.com with HTTP; Tue, 06 May 1997 23:58:45 PDT X-Originating-IP: [158.250.32.157] From: "Alexey Serov" To: chemistry@ccl.net Subject: Subscribe Content-Type: text/plain Date: Tue, 06 May 1997 23:58:45 PDT Subscribe chemistry computational list vores@hotmail.com --------------------------------------------------------- Get Your *Web-Based* Free Email at http://www.hotmail.com --------------------------------------------------------- From akutatel@du.edu Wed May 7 16:41:45 1997 Received: from odin.cair.du.edu for akutatel@du.edu by www.ccl.net (8.8.3/950822.1) id PAA01730; Wed, 7 May 1997 15:59:28 -0400 (EDT) Received: by odin.cair.du.edu; id AA32619; Wed, 7 May 1997 13:59:26 -0600 Received: by kizh.biochem.du.edu with Microsoft Mail id <01BC5AEE.60AB8120@kizh.biochem.du.edu>; Wed, 7 May 1997 13:55:53 -0600 Message-Id: <01BC5AEE.60AB8120@kizh.biochem.du.edu> From: Andrei Kutateladze To: "'CCL'" Cc: "'toukie@zui.unizh.ch'" Subject: CCL: SUMMARY: Torsional barriers for methyl group rotation Date: Wed, 7 May 1997 13:55:51 -0600 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit A couple of days ago I posted the following question: > A colleague of my is looking for reliable experimental data on >torsional barriers for methyl group rotation in various environments - >aromatic, n-alkyl, branched alkyl, ether etc. > Any references will be much appreciated. Many thanks to people who replied. Special thanks to Wolfgang Roth for quite a comprehensive refs list. Andrei Kutateladze University of Denver SUMMARY: =========================================== REPLY # 1 You may look at this http://www-public.rz.uni-duessledorf.de/~rothw/diplom/literatur.html part of my homepage where I placed the list of literature from my dissertation. Experimental methyl group torsion parameters of aromatic compounds are available fo the following molecules (to my knowledge): toluene (see Refs. 15, 29, 56 of the above mentioned website, see also J. Chem. Phys. 102 (1995) 6787, J. Chem. Phys. 102 (1995) 8718) 1-methyltetrazene (Refs. 44, 58) 3-fluortoluene (Ref. 27) 4-fluortoluene (Refs. 27, 44) (I wasn't interested in 2-fluortoluene) cis-3-cresol (Ref. 13) 3-methylindole (Ref. 59) 5-methylindole (Refs. 41, 59) 6-methylindole (Ref. 41) 3- and 4-methylbenzylradical (Ref. 28) 2-Methylpyrazine (Ref. 60) 2-Methylnaphthalene (Ref. 17) (data for 1-MN are also available) methylcyclopentadienylradical (Ref. 20) 4- and 5-methylpyrimidine (Ref. 38) 4-toluidine (Refs. 42, 54) Further molecules which have been investigated are xylenes acetone (lot of papers in J. Molec. Spect., maily from IR spectra for different torsional modes. methylglyoxale (Ref. 73) methanol (very early microwave papers in J. Chem. Phys.) CH3SH trans-beta-methylstyrene (J. Phys. Chem. 99 (1995) 4386 acetaldehyde (e.g. J. Mol. Struct. 350 (1995) 83) methyl-subtituted stilbenes (work of Spangler and coworkers, e.g. J. Phys. Chem. 99 (1995) 9316) methylacetylene ... I decided to cut the list here because I have approximately 100 to 150 references to experimental and theoretical papers dealing with internal rotation maily of the methyl group. I don't have informations about ether because this molecules are not accessible to medium or high resolution laser induced fluorescence. If You/Your colleague is interested in the whole list which is an Excel 4.0 file, please send me an email. Regards Wolfgang Roth ====================== REPLY # 2 Andrei, The following reference might be useful: Cohen, N.; Benson, S. W. In "The chemistry of Alkanes and Cycloalkanes"; Patai, S.; Rappoport, Z., Ed.; John Wiley, 1992; Chapter 6. Regards, Ashutosh (Misra Ashutosh, ashutosh@jove.acs.unt.edu) ======================= REPLY # 3 Dear Andrei Kutateladze, There is a table of about twenty or so methyl barriers in a book on thermodynamics: "Thermodynamics of Organic Compounds in the Gas State", Volume I, Michael Frenkel, K.N. Marsh, R. C. Wilhoit, G. J. Kabo, G. N. Roganov page 26. A recent paper in JCP deals with internal rotation treated by ab innitio methods, and some of references there may lead to experimental data. Russ Dr. Russell D. Johnson III Research Chemist Physical and Chemical Properties Division National Institute of Standards and Technology Gaithersburg, MD 20899 email: russell.johnson@nist.gov From huber@library.ucsb.edu Wed May 7 19:02:40 1997 Received: from ariz.library.ucsb.edu for huber@library.ucsb.edu by www.ccl.net (8.8.3/950822.1) id RAA17178; Wed, 7 May 1997 17:43:58 -0400 (EDT) Received: by ariz.library.ucsb.edu (5.65/DEC-Ultrix/4.3) id AA24882; Wed, 7 May 1997 14:43:55 -0700 Date: Wed, 7 May 1997 14:43:55 -0700 (PDT) From: Chuck Huber To: chemistry@www.ccl.net Subject: Chemical Structure Association Award (fwd) Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII The following message is being posted to multiple listservs; please pardon any duplication. ======================================================= CHEMICAL STRUCTURE ASSOCIATION AWARD FOR US STUDENT The Chemical Structure Association (CSA) is an international organisation which aims to bring together people whose work involves the handling of information about chemical structures. Members of the CSA are interested in all aspects of chemical structure information, including molecular modelling, combinatorial chemistry, computer systems for handling chemical structural information, chemical databases, online systems, use of the Internet to access chemical information, and manual and CD-ROM reference tools. The CSA is offering an Award of 210 US dollars to assist a US student to attend the Fall ACS meeting in Las Vegas. Students may be undergraduate or postgraduate, and should be specialising in some aspect of chemical structure information handling. Applicants must be students at the time of application for the award, but need not necessarily be a student at the time of the meeting. The value of the award is equivalent to the full registration fee for the meeting. Applications for the award should be sent, together with a supporting reference, by 1 June 1997 (deadline extended) to: Chuck Huber, Chairman of CINF Awards Committee, Davidson Library University of California Santa Barbara, CA 93106 e-mail: huber@ariz.library.ucsb.edu Chuck Huber Davidson Library University of California Santa Barbara huber@library.ucsb.edu