From brian@bert.chem.wsu.edu Fri Feb 7 04:21:41 1997 Received: from pegasus.it.wsu.edu for brian@bert.chem.wsu.edu by www.ccl.net (8.8.3/950822.1) id DAA07752; Fri, 7 Feb 1997 03:22:59 -0500 (EST) Received: from bert.chem.wsu.edu (bert.chem.wsu.edu [134.121.43.22]) by pegasus.it.wsu.edu (8.8.5/8.8.5) with SMTP id AAA09835 for ; Fri, 7 Feb 1997 00:22:53 -0800 (PST) Received: by bert.chem.wsu.edu (AIX 3.2/UCB 5.64/4.03) id AA13049; Fri, 7 Feb 1997 00:23:23 -0800 From: brian@bert.chem.wsu.edu (Brian W. Beck) Message-Id: <9702070823.AA13049@bert.chem.wsu.edu> Subject: CCL:ESP charges To: CHEMISTRY@www.ccl.net (Computational Chemistry List) Date: Fri, 7 Feb 1997 00:23:23 -0800 (PST) X-Mailer: ELM [version 2.4 PL24] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit What experimental techniques are available to correlate (or even verify, as the case may be) ESP derived partial charges? I realize that if there were a perfect technique there wouldn't be this running thread of Mulliken vs. ESP vs. NBO charges, but let's say I have two compounds with similar partial charges that I expected to be different. Is there an experimental technique that can be used to verify at least the relative magnitude of the charges between the two compounds? -Brian -- ============================================================================= | .---------.| Brian W. Beck | E-mail Addresses: | |/\ | || Biochem/Biophysics | brian@bert.chem.wsu.edu | || \\ WSU || Washington St. Univ| brian_beck@wsu.edu | |\ - *|| 639 Fulmer | URL http://elmo.chem.wsu.edu/~brian | | | || Pullman, WA, USA | VOICE (509) 335-4083 | | \___________|| 99164-4660 | FAX (509) 335-9688 | ============================================================================= From peon@medchem.dfh.dk Fri Feb 7 06:21:32 1997 Received: from danpost.uni-c.dk for peon@medchem.dfh.dk by www.ccl.net (8.8.3/950822.1) id FAA08291; Fri, 7 Feb 1997 05:51:09 -0500 (EST) Received: from medchem.dfh.dk (medchem.dfh.dk [130.225.177.15]) by danpost.uni-c.dk (8.7.5/8.6) with SMTP id LAA07982 for <@danpost.uni-c.dk:CHEMISTRY@www.ccl.net>; Fri, 7 Feb 1997 11:51:08 +0100 (MET) Received: from [130.225.177.59] (compmac2 [130.225.177.59]) by medchem.dfh.dk (950413.SGI.8.6.12/950213.SGI.AUTOCF) via SMTP id MAA24730 for ; Fri, 7 Feb 1997 12:21:51 +0100 Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Fri, 7 Feb 1997 11:51:07 +0100 To: CHEMISTRY@www.ccl.net From: peon@medchem.dfh.dk (Per-Ola Norrby) Subject: Re: CCL:ESP charges > What experimental techniques are available to correlate > (or even verify, as the case may be) ESP derived partial charges? The simplest would be the dipole. It can only be used for neutral molecules, and only gives an overall estimate. Specific charges could very well be "wrong", but still give a good dipole. This is especially true if a fit to the dipole has been used in deriving the charges. I have been wondering myself, could ESCA measurements be assumed to be correlated with "absolute charge"? It has often been assumed that 13C NMR shifts correlate with charge, but that approximation breaks down easily when you do large strucutral changes. Per-Ola Norrby ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * Per-Ola Norrby, Associate Professor * The Royal Danish School of Pharmacy, Dept. of Med. Chem. * Universitetsparken 2, DK 2100 Copenhagen, Denmark * tel. +45-35376777-506, +45-35370850 fax +45-35372209 * Internet: peon@medchem.dfh.dk, http://compchem.dfh.dk/ From Jeffrey.Gosper@brunel.ac.uk Fri Feb 7 08:21:35 1997 Received: from ceres.brunel.ac.uk for Jeffrey.Gosper@brunel.ac.uk by www.ccl.net (8.8.3/950822.1) id IAA08858; Fri, 7 Feb 1997 08:08:10 -0500 (EST) Received: from chem-pc-18 (actually chem-pc-18.brunel.ac.uk) by ceres.brunel.ac.uk with SMTP (PP); Fri, 7 Feb 1997 13:06:13 +0000 Date: Fri, 7 Feb 1997 13:06:10 GMT From: Jeffrey J Gosper Subject: Re: CCL:spectra visualization To: hassler cc: CHEMISTRY@www.ccl.net Message-ID: Priority: Normal MIME-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=US-ASCII Content-Transfer-Encoding: 8bit On Wed, 5 Feb 97 12:34:19 +0100 hassler wrote: > From: hassler > Date: Wed, 5 Feb 97 12:34:19 +0100 > Subject: CCL:spectra visualization > To: chemistry@ccl.net > > > Dear members of CCL! > > I am looking for a program that depicts and draws (visualizes) > IR spectra and Raman spectra > if you input calculated ab initio wavenumbers and relative (IR,Ra) intensities. > I guess there are programs that use an appropriate output of gamess or gaussian? > I hope you can help me! > Nice greetings to everyone > > K. Hassler (Department of inorganic chemistry, TU Graz, Austria) > present e-mail: > hassler@ftug01.tu-graz.ac.at > > > We are thinking of writing one. So if you find one please inform us. We did have a look at a demo of a program called AniMOL by Inivative Software Inc about a year ago. It displayed a type of I.R. spectrum from data from G80. It also animated the displacements (we didn't need this as we have Re_View2 for this). The cost of the program was it was around £300 per copy. One of the reasons I set up the 'standard vibration file' in Re_View2 was directed at spectral simulation. I included scaling factors, intensitieties, symmetries, etc such that good spectra could be simulated. From a users point of view what features would you like to see e.g. 1) A GAMESS, MOPAC, G94 interface 2) Specification on individual/global frequency scaling factors 3) Specification of the linewidth 4) The ability to expand/scroll thea spectrum. 5) A link tfrom the peak to an animations of vibration. 6) The ability to compare real spectra. What else? /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ Dr. Jeff Gosper Dept. of Chemistry BRUNEL University Uxbridge Middx UB8 3PH, UK voice: 01895 274000 x2187 facsim: 01895 256844 internet/email/work: Jeffrey.Gosper@brunel.ac.uk internet/WWW: http://www.brunel.ac.uk/~castjjg Re_View's Home page (A molecular display/animation/analysis program): http://www.brunel.ac.uk/depts/chem/ch241s/re_view/re_view.htm \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/