From dario@rs5.csrsrc.mi.cnr.it Wed Jan 22 06:18:00 1997 Received: from rs5.csrsrc.mi.cnr.it for dario@rs5.csrsrc.mi.cnr.it by www.ccl.net (8.8.3/950822.1) id FAA12344; Wed, 22 Jan 1997 05:37:06 -0500 (EST) Received: by rs5.csrsrc.mi.cnr.it (AIX 3.2/UCB 5.64/4.03) id AA10111; Wed, 22 Jan 1997 11:37:35 +0100 Date: Wed, 22 Jan 1997 11:37:35 +0100 From: dario@rs5.csrsrc.mi.cnr.it (Dario Bressanini) Message-Id: <9701221037.AA10111@rs5.csrsrc.mi.cnr.it> To: CHEMISTRY@www.ccl.net Subject: Clarification on the question "What is EXACTLY a resonance" Dear CCLers I should have been more accurate in in posing my question. It seems that people interpreted the question "What is EXACTLY a resonance" in two different ways. Just to be more clear, I am NOT talking about "resonances" in the sense of resonance between different structures like in benzene. I don't want to open a "can of worm" but i think this kind of "resonance" is more an effect of our inability to accurately describes molecules than a real physical effect. I was asking about the resonances you see in scattering experiments for example in the experiment H + H- you see a "resonance" due to (probably) the H2- molecule which is not stable since its energy lies in the continuum of H2+e Dario Bressanini Dario@rs0.csrsrc.mi.cnr.it From ragno@naxos.caspur.it Tue Jan 21 03:26:17 1997 Received: from mail.caspur.it for ragno@naxos.caspur.it by www.ccl.net (8.8.3/950822.1) id DAA03516; Tue, 21 Jan 1997 03:06:21 -0500 (EST) Received: from naxos.caspur.it (naxos.caspur.it [193.204.5.8]) by mail.caspur.it (8.8.4/8.8.4) with ESMTP id JAA25098 for ; Tue, 21 Jan 1997 09:05:50 +0100 Received: from localhost (ragno@localhost) by naxos.caspur.it (8.8.4/8.8.4) with SMTP id JAA25666 for ; Tue, 21 Jan 1997 09:05:50 +0100 (MET) Date: Tue, 21 Jan 1997 09:05:49 +0100 (MET) From: Gianluca Sbardella To: chemistry@www.ccl.net Subject: Molar absorbivity of NNRTI Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Dear Colleagues, I'm a medicinal chemist at the University of Rome (Italy). My research team is very interested in NNRTI (non nucleoside reverse transcriptase inhibitors). We're looking for molar absorbivity constants (UV determination) of some well-known NNRTI (nevirapine, TIBO, HEPT, MKC 442). Could anybody help us (references, addresses or whatsoever...)? Thank you very much in advance, Dr. Gianluca Sbardella *************************************************************** * * * Dr. Gianluca Sbardella E-mail: r.ragno@caspur.it * * Dip. Studi Farmaceutici * * Universita' "La Sapienza" Phone: 39-6-49913814 * * P.le A. Moro, 5 Fax: 39-6-491491 * * 00185 Roma * * ITALY * * * *************************************************************** From ccl@www.ccl.net Tue Jan 21 11:18:03 1997 Received: from bedrock.ccl.net for ccl@www.ccl.net by www.ccl.net (8.8.3/950822.1) id LAA05886; Tue, 21 Jan 1997 11:09:57 -0500 (EST) Received: from myriad.cis.pitt.edu for SATYAM@vms.cis.pitt.edu by bedrock.ccl.net (8.8.3/950822.1) id LAA26594; Tue, 21 Jan 1997 11:09:54 -0500 (EST) From: Received: from vms.cis.pitt.edu by vms.cis.pitt.edu (PMDF V4.3-10 #16365) id <01IEH0ZCA7E895Y0EL@vms.cis.pitt.edu>; Tue, 21 Jan 1997 11:09:50 -0400 (EDT) Date: Tue, 21 Jan 1997 11:09:50 -0400 (EDT) Subject: PROBLEMS WITH G94 on R8000 with IRIX6.2.. To: chemistry@ccl.net Message-id: <01IEH0ZCBA0I95Y0EL@vms.cis.pitt.edu> X-Envelope-to: chemistry@ccl.net X-VMS-To: IN%"chemistry@ccl.net" MIME-version: 1.0 Content-type: TEXT/PLAIN; CHARSET=US-ASCII Content-transfer-encoding: 7BIT Dear Netters, I would appreciate if anyone of you have faced similar problem like this on IRIX6.2 on R8000 and Gaussian94.. Problem : When monitoring a running Gaussian Job using Unix command top we see that the same process id of the G94 link (submitted by user1) is shown to be owned by root and other users of the system (incl. user1) as "top" refreshes it's screen. Even while other users are not logged on. Please respond to me (satyam+@pitt.edu) or Marc(pedulla+@pitt.edu). Thanks Satyam and Marc From watts@gwinn.medc.umn.edu Tue Jan 21 19:17:54 1997 Received: from chet.medc.umn.edu for watts@gwinn.medc.umn.edu by www.ccl.net (8.8.3/950822.1) id SAA09572; Tue, 21 Jan 1997 18:20:37 -0500 (EST) Received: from gwinn.medc.umn.edu (root@gwinn.medc.umn.edu [160.94.158.215]) by chet.medc.umn.edu (8.8.3/8.6.9) with ESMTP id RAA22713 for ; Tue, 21 Jan 1997 17:20:37 -0600 (CST) Received: from localhost (watts@localhost) by gwinn.medc.umn.edu (8.8.3/8.6.9) with SMTP id RAA13963 for ; Tue, 21 Jan 1997 17:20:35 -0600 (CST) Date: Tue, 21 Jan 1997 17:20:35 -0600 (CST) From: Chuck Watts To: The Computational Chemistry List Subject: Protein Hydration and Spectral Density Functions. (fwd) Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Dear CCL: I have a small queation for you that is not completely computational in nature although it does pertain to the investigation of biomolecular dynamics using NMR and I know that many NMR spectroscopists subscribe to this list. I was recently reading the papers Otting, G.; Liepinsh, E.; Wutrich, K. (1991) "Protein Hydration in Aqueous Solution" Science 254, 974-980. and Kubinec, M. G.; Wemmer, D. E. (1992) "NMR Evidence for DNA Bound Water in Solution" JACS 114, 8739-8740. In these papers combined NOESY and ROESY experiments are used to measure the lifetimes of waters bound to BPTI and DNA as interpreted by a Random Diffusion model. The model consists of a protein molecule with a radius rp, a proton spin displaced from the protein center by pp, and a rotational correlation time of tp, a water molecule with a radius rw, a proton spin displaced from the water center by pw, and a rotational correlation time of tw, the protein and water are related to each other via the diffusion coefficient D which can then be translated into a correlation time for the interaction using the Einstein-Smoluchowski relation. The NOE and ROE rates dependency on the spectral density function are then given as k(NOE) = 6J(2wo) - J(0) k(ROE) = 3J(wo) + 2J(0) and it is stated that the spectral density is related to the rate processes that govern the modulation of the dipole-dipole coupling of the system. My question is as follows, I can easily find the generic treatment of the spectral density function that relates its dependency on a single correlation time with the assumption of isotropic tumbling, how is the spectral density function used in these studies different from this and how specifically did they generate the NOE/ROE vs. 1/D curves for this paper given the data above. Sorry, I know this pobably isn'y a short queation but I thought someone on the list might have some insight as to the solution. Best Wishes, Charles R. Watts ************************************ Department of Medicinal Chemistry * * College of Pharmacy * An appeaser is one who feeds * University of Minnesota * a crocodile, hoping it will eat * 8-101 HSUF * him last. * 308 Harvard St. SE. * * Minneapolis, MN 55455 * -Winston Churchill * Phone: (612) 624-5486 * * Fax: (612) 626-4429 * * E-Mail: watts004@128.101.118.21 ************************************ From rozas@pinar1.csic.es Wed Jan 22 11:18:05 1997 Received: from pinar.csic.es for rozas@pinar1.csic.es by www.ccl.net (8.8.3/950822.1) id KAA14321; Wed, 22 Jan 1997 10:18:09 -0500 (EST) Received: from pinar.csic.es by pinarvms.csic.es (PMDF V5.1-4 #13290) id <01IEIQ4KTBPS0071VH@pinarvms.csic.es> for chemistry@www.ccl.net; Wed, 22 Jan 1997 16:19:33 CE X400-Received: by /PRMD=iris/ADMD=mensatex/C=es/; Relayed; Wed, 22 Jan 1997 16:14:59 +0000 Date: Wed, 22 Jan 1997 16:14:59 +0000 From: Isabel Rozas Subject: searching for software To: chemistry@www.ccl.net Message-id: <610*rozas@pinar1.csic.es> Content-identifier: 610 MIME-version: 1.0 (Generated by Ean X.400 to MIME gateway) X400-Content-type: P2-1984 (2) X400-MTS-identifier: [/PRMD=iris/ADMD=mensatex/C=es/;970122161459] X400-Originator: rozas@pinar1.csic.es X400-Recipients: non-disclosure:; Hello everybody, I would really appreciate some help and information about two kinds of software: 1) X-windows emulators for Mac's (Power Macintosh type) and 2) Programs to manipulate and visualize nmr spectra that run or in Mac's or in X-windows I don't mind if they are comercial or free programs, what I have been asked for by my Institute are good programs even if they are not cheap. Thanks a lot Isabel Rozas ----------------------------------------------------------------------- Isabel Rozas ROZAS@PINAR1.CSIC.ES Instituto de Quimica Medica (C.S.I.C.) Phone: 34-1-562 2900 c/ Juan de la CIerva 3 Fax: 34-1-564 4853 28003-Madrid (Spain) ----------------------------------------------------------------------- From nash@chem.wisc.edu Wed Jan 22 11:26:42 1997 Received: from humvee.doit.wisc.edu for nash@chem.wisc.edu by www.ccl.net (8.8.3/950822.1) id KAA14441; Wed, 22 Jan 1997 10:46:17 -0500 (EST) Received: from audumla.students.wisc.edu by humvee.doit.wisc.edu; id JAA54224; 8.7.5/50; Wed, 22 Jan 1997 09:45:33 -0600 Received: from [144.92.91.209] by audumla.students.wisc.edu; id JAA66392; 8.6.9W/42; Wed, 22 Jan 1997 09:44:57 -0600 X-Sender: jrnash@144.92.104.66 Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 22 Jan 1997 09:44:56 -0600 To: CHEMISTRY@www.ccl.net From: "John R. Nash" Subject: Rebirth of resonance... dario@rs5.csrsrc.mi.cnr.IT asked about "resonance" of a different kind, but in of the CCL replies: korkin@qtp.ufl.edu said: >Probably, the most close analogy among the resonance "theory" and quantum >mechanics is represented by generalized valence bond (GVB) scheme. But >the valence structures in GVB is not exactly what organic chemists mean >by "resonance". We can say that a few valence structures in GVB correspond >to one structure in resonance theory. > >You may look in Dewar books. I do not think computational and theoretical >chemist care a lot about "resonance" nowdays. Since "this kind" of resonance has been brought up, I thought I should mention that many chemists still do care about it. It is certainly a useful teaching aid for undergraduate organic chemistry students, and practicing lab and theoretical chemists often find resonance structures useful "when one Lewis Structure just won't do" to describe a delocalized system. This is especially true in organometallics, where one structure seldom tells the whole story, even for a simple complex. As far as the theoreticians go, F. A. Weinhold's NBO program (most often used along with G94, but available as a standalone program) can generate weighted resonance structures (i.e. 40% contribution from A, 23% contribution from B, etc.) for a delocalized system. So Pauling's and others' "approximate, chemical intuition" ideas on resonance can actually be quantified into useful numbers these days. See the NBO manual and Weinhold's papers for more details. -john -==-John R. Nash-==-nash@chem.wisc.edu-==-UW-Madison Chem. Dept-==- --- "When in doubt, roll!" --- From mikha001@maroon.tc.umn.edu Wed Jan 22 13:18:10 1997 Received: from mhub1.tc.umn.edu for mikha001@maroon.tc.umn.edu by www.ccl.net (8.8.3/950822.1) id MAA23093; Wed, 22 Jan 1997 12:56:00 -0500 (EST) Received: from maroon.tc.umn.edu by mhub1.tc.umn.edu; Wed, 22 Jan 97 11:55:51 -0600 Received: by maroon.tc.umn.edu; Wed, 22 Jan 97 11:55:51 -0600 Date: Wed, 22 Jan 1997 11:55:41 -0600 (CST) From: Dmitri V Mikhailov To: chemistry@www.ccl.net Subject: Cremer - Pople parameters Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Dear Netters, I need to calculate Cremer - Pople ring puckering parameters (Cremer and Pople, J.Amer.Chem.Soc. 97, 1354-1358 (1975)) for trajectories generated with Biosym/MSI software. Can someone point me to any available C or Fortran routines which do this sort of calculation. Regards, Dmitri Mikhailov Ph.D. student ***************************************************** Univ. of Minnesota Medical School Department of Biochemistry Box 609, 420 Delaware St. SE Minneapolis MN 55455 tel. (612) 624-7107 fax. (612) 626-2325 e-mail: mikha001@maroon.tc.umn.edu ***************************************************** From huang@nissan.wavefun.com Wed Jan 22 13:22:39 1997 Received: from volvo.wavefun.com for huang@nissan.wavefun.com by www.ccl.net (8.8.3/950822.1) id NAA23136; Wed, 22 Jan 1997 13:05:22 -0500 (EST) Received: by volvo.wavefun.com (931110.SGI/930416.SGI) for chemistry@www.ccl.net id AA08894; Wed, 22 Jan 97 10:06:26 -0800 Received: from nissan.wavefun.com(198.147.95.2) by volvo.wavefun.com via smap (V1.3) id sma008890; Wed Jan 22 10:06:14 1997 Received: by nissan.wavefun.com (931110.SGI/940406.SGI.AUTO) for @volvo.wavefun.com:chemistry@www.ccl.net id AA16585; Wed, 22 Jan 97 10:05:00 -0800 From: "Wayne Huang" Message-Id: <9701221004.ZM16583@nissan.wavefun.com> Date: Wed, 22 Jan 1997 10:04:51 -0800 In-Reply-To: "Daniel J. Berger" "CCL:PM3 parameters for boron" (Jan 21, 1:45pm) References: <01BC07A1.57838F20@bergerd.bluffton.edu> Reply-To: huang@wavefun.com X-Mailer: Z-Mail (3.2.2 10apr95 MediaMail) To: "Daniel J. Berger" , "'Computational Chemistry List'" Subject: Re: CCL:PM3 parameters for boron Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii On Jan 21, 1:45pm, Daniel J. Berger wrote: > Subject: CCL:PM3 parameters for boron > Last I checked (just a couple years ago) there weren't any PM3 parameters for boron, but have any been generated recently? > > Thank you very much! > > Daniel J. Berger PH: (419) 358-3379 > Bluffton College FAX:(419) 358-3323 > 280 W. College Avenue bergerd@bluffton.edu > Bluffton OH 45817-1196 > > http://cs.bluffton.edu/~berger/ > I believe this inquiry has been circulated once a while back. Spartan PM3 module has been parametrized for boron. Such parameters have been available for almost two years now. However we have not published in the literature yet. Contact me (support@wavefun.com) for further information. --Wayne -- +---------------------------------------------------------------+ | Wayne Huang, Ph.D. | 18401 Von Karman, Suite 370 | | Computational Chemist | Irvine, California 92612 | | Wavefunction, Inc. | 714-955-2120 <> 955-2118(fax)| | huang@wavefun.com | Web: http://www.wavefun.com | +---------------------------------------------------------------+ From JANET.CICARIELLO-COOK@roche.com Wed Jan 22 13:24:13 1997 Received: from gatekeeper.roche.com for JANET.CICARIELLO-COOK@roche.com by www.ccl.net (8.8.3/950822.1) id MAA22932; Wed, 22 Jan 1997 12:32:56 -0500 (EST) Received: by gatekeeper.roche.com (5.65v3.2/fma-120691); id AA07340; Wed, 22 Jan 1997 12:26:22 -0500 Received: from rnudnb.nut.roche.com by mailgate.roche.com; (5.65v3.2/1.1.8.2/20Mar96-0227PM) id AA11692; Wed, 22 Jan 1997 12:27:00 -0500 Received: from mr.nut.roche.com by rnuc01.nut.roche.com (PMDF V5.0-6 #9043) id <01IEIHYYLSY8HSJJLU@rnuc01.nut.roche.com>; Wed, 22 Jan 1997 12:26:47 -0500 (EST) Received: with PMDF-MR; Wed, 22 Jan 1997 12:25:35 -0500 (EST) Mr-Received: by mta RNIS08; Relayed; Wed, 22 Jan 1997 12:25:35 -0500 Mr-Received: by mta RNUC01; Relayed; Wed, 22 Jan 1997 12:26:41 -0500 Alternate-Recipient: prohibited Date: Wed, 22 Jan 1997 12:25:33 -0500 (EST) From: JANET CICARIELLO-COOK 57165 Subject: re: Searching for Software To: chemistry@www.ccl.net Cc: rozas@pinar1.csic.es Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=US-ASCII Content-Transfer-Encoding: 7BIT Posting-Date: Wed, 22 Jan 1997 12:25:35 -0500 (EST) Importance: normal Priority: normal Ua-Content-Id: E1111IRE2O5IL X400-Mts-Identifier: [;53522122107991/301799@RNISD0] A1-Type: MAIL Hop-Count: 2 I have been using MacX as an X-terminal emulator for my PowerMac and have been happy with it. I use it to access SYBYL (running on our SGI's) from my PowerMac 7600/132. It even works when I'm connected to Roche from home (subject to modem speed, of course ;-) with a PowerMac 7100/80. I'm not sure if a PowerMac is required for MacX. MacX is available from MacWarehouse. (http://www.warehouse.com/macwarehouse/) Janet ********************************************* * Janet Cicariello-Cook, Ph.D. * * Hoffmann-LaRoche, Inc. * * 340 Kingsland St. * * Nutley, NJ 07110 * * ph: (201) 235-7165 * * fax: (201) 235-7292 * * e-mail: janet.cicariello-cook@roche.com * ********************************************* >>Hello everybody, >>I would really appreciate some help and information about two kinds >>of software: >> >>1) X-windows emulators for Mac's (Power Macintosh type) and >>2) Programs to manipulate and visualize nmr spectra that run or in Mac's >>or in X-windows >> >>I don't mind if they are comercial or free programs, what I have been >>asked for by my Institute are good programs even if they are not cheap. >> >>Thanks a lot >> >> Isabel Rozas >> >>----------------------------------------------------------------------- >> Isabel Rozas ROZAS@PINAR1.CSIC.ES >> Instituto de Quimica Medica (C.S.I.C.) Phone: 34-1-562 2900 >> c/ Juan de la CIerva 3 Fax: 34-1-564 4853 >> 28003-Madrid (Spain) >>----------------------------------------------------------------------- >> From borghet@ipruniv.cce.unipr.it Wed Jan 22 15:18:06 1997 Received: from ipruniv.cce.unipr.it for borghet@ipruniv.cce.unipr.it by www.ccl.net (8.8.3/950822.1) id OAA24219; Wed, 22 Jan 1997 14:47:53 -0500 (EST) From: Received: by ipruniv.cce.unipr.it (AIX 3.2/UCB 5.64/4.03) id AA47568; Wed, 22 Jan 1997 20:47:50 +0100 Date: Wed, 22 Jan 1997 20:47:50 +0100 (NFT) Subject: CCL:searching for molecular modelling software To: chemistry@www.ccl.net Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Hello everybody, I would appreciate help and information about molecular modelling software that run on Alpha workstation I don't mind if they are comercial or free programs, what I have been asked for by my Institute are good programs and not too expensive. Thanks a lot --------------------------------------- Antonello Romani | Istituto di Patologia Generale | | Tel (39) +521 291-583 | Fax (39) +521 980-388 | E-mail: borghet@ipruniv.cce.unipr.it | via Gramsci 14 | 43100 Parma | Italia | --------------------------------------- From yt203@cus.cam.ac.uk Wed Jan 22 17:18:07 1997 Received: from taurus.cus.cam.ac.uk for yt203@cus.cam.ac.uk by www.ccl.net (8.8.3/950822.1) id RAA24940; Wed, 22 Jan 1997 17:16:45 -0500 (EST) Received: from yt203 by taurus.cus.cam.ac.uk with smtp (Exim 1.592 #2) id 0vnAyI-0003Yt-00; Wed, 22 Jan 1997 22:16:42 +0000 Date: Wed, 22 Jan 1997 22:16:41 +0000 (GMT) From: "Y. Tantirungrotechai" To: chemistry@www.ccl.net Subject: MD.simulation on PC ? Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Dear Sir, Are there any MD programmes available which run on a PC (Pentium), e.g. DOS or Linux ? I am especially interested in FORTRAN codes and would be grateful for any information regarding resources, i.e. what system specifications are needed to simulate up to 1000 water molecules (possibly polarisable). I would appreciate any comments on this matter. Thank you for your time, yours sincerely Yuthana Yuthana yt203@cam.ac.uk From sxr224@anugpo.anu.edu.au Wed Jan 22 20:18:08 1997 Received: from anugpo.anu.edu.au for sxr224@anugpo.anu.edu.au by www.ccl.net (8.8.3/950822.1) id UAA25624; Wed, 22 Jan 1997 20:08:05 -0500 (EST) Received: from surya.anu.edu.au (surya.anu.edu.au [150.203.193.135]) by anugpo.anu.edu.au (8.8.4/8.8.3) with SMTP id MAA07347; Thu, 23 Jan 1997 12:07:59 +1100 (EST) Message-Id: <199701230107.MAA07347@anugpo.anu.edu.au> Comments: Authenticated sender is From: "Shoba.Ranganathan" To: chemistry@www.ccl.net, tamasgunda@tigris.klte.hu Date: Thu, 23 Jan 1997 11:42:28 +0000 Subject: CCL:SUMM: AM1 Proton Affinities Reply-to: Shoba.Ranganathan@anu.edu.au Priority: normal X-mailer: Pegasus Mail for Windows (v2.23) I am posting an abbreviated version of the replies to my query, and with names and e.mail addresses: > Does anyone have a reference for AM1 or semi-empirical proton > affinity calculations? I am very grateful to all those who responded. Shoba ====================================================================== J. L. Ozment and A. M. Schmiedekamp, International J. Quant. Chem. 43, 783-800 (1992). From: SCHMIED@FCRFV1.NCIFCRF.GOV ====================================================================== and the same reference with the following comment: They concluded that AM1 is able to predict the relative PA's, while the results of PM3 scatters. Kazuo Teraishi (JDA03546@niftyserve.or.jp) ====================================================================== I have found 2 references particularly helpful in choosing a method. J. Ozment & A. Schmiedekamp, Int. J. Quant. Chem., 43, 783-800 (1992) compares the accuracy of MNDO, AM1, and PM3 calculations of some 110 proton affinities, and Fitzgerald & Andzelm, J. Phys. Chem., 95, 10531-4 (1991) compares DFT methods with MP2 calculations of 12 proton affinities. Ernest Chamot (echamot@xnet.com) ====================================================================== Here is a reference of AM1 calculated Proton Affinities: M.J.S. Dewar, K.M. Dieter, J. Am. Chem. Soc. 1986,108, 8075. This reference is slightly old, but hope would serve the purpose. Bishwajit (lara@chemdc1.tau.ac.il) ====================================================================== I have published on proton affinities in Group 14 elements (using PM3 to generate the numbers) in J. Mol. Struct. (THEOCHEM) 338 (1995) 51-70. Daniel J. Berger (bergerd@bluffton.edu) ====================================================================== I would like to point out my own paper. "The role of amphotericin B amino group basicity in its antifungal action. A theoretical approach" M.Baginski, P.Gariboldi, E.Borowski Biophys.Chem. 49 (1994) 241-250 You may check it since we did some calculations of proton affinity by AM1 and MNDO methods for models of amphotericin B derivatives but also for 25 simple organic molecules (organic amines). We have found the correlation between calcualted and experimantal values of PA for these 25 compounds. We also site other papers concerning this subject. Maciej Baginski (maciekb@altis.chem.pg.gda.pl) ====================================================================== Have a look at Dewar & Dieter, JACS 1986, 108, 8075 Benzion Fuchs (bfuchs@ccsg.tau.ac.il or fuchs@chemdc1.tau.ac.il) ====================================================================== I have one reference concerning the use of MNDO and AM1 for the prediction of proton affinities of aza-arenes: J.F.Sanz, J. Anguino, J.Vilarrasa: J. Comput. Chem. 9, 784 (1988) Another one, by myself, deals with the application of semiempirical effective electronic potentials: J.Spanget-Larsen: "Structure-reactivity correlations for aza-arenes. Proton affinities, pKa values, hydrogen-deuterium exchange rates and radical-induced C13 shifts", J. Phys. Org. Chem. 8, 496-505 (1995). JENS SPANGET-LARSEN (JSL@virgil.ruc.dk) ====================================================================== For AM1 you should look at M.J.S.Dewar and K.M.Dieter, JACS, 108, 8075 (1985), for PM3 i would suggest our own article P.Burk, K.Herodes, I. Koppel and I. Koppel, Int.J.Quantum Chem.: Quantum Chem.Symp. 27,633 (1993) Peeter Burk (peeter@chem.ut.ee) ====================================================================== You may had better refer the reference listed below. 1)Dewar, M. J. S.; Dieter, K. M. J. Am. Chem. Soc., 108, 8075(1986). 2)Taft, R.W.; Racynskay, E.D.; Maria, P.-C.;Leito, I.; Gal. J.-F.; Decouzon, M.; Drapala, T.; Anvia, F. Pol. J. Chem. 1995,59,41. KANZAKI KOJI (kanzaki@mxk.meshnet.or.jp) ====================================================================== Do you know the article of S.J.Dixon et al. on the estimation of pK using calculated atomic charges, in J.Comput.Chem. vol14, 1460 (1993)? Dr Tamas E. Gunda (tamasgunda@tigris.klte.hu) ********************************************************************** From noy@einstein.sc.mahidol.ac.th Wed Jan 22 23:18:09 1997 Received: from einstein.sc.mahidol.ac.th for noy@einstein.sc.mahidol.ac.th by www.ccl.net (8.8.3/950822.1) id XAA26428; Wed, 22 Jan 1997 23:15:47 -0500 (EST) Received: (from noy@localhost) by einstein.sc.mahidol.ac.th (8.7.4/8.7.3) id KAA03220 for chemistry@www.ccl.net; Thu, 23 Jan 1997 10:59:54 -0700 From: "Dr. Teerakiat Kerdcharoen" Message-Id: <199701231759.KAA03220@einstein.sc.mahidol.ac.th> Subject: references on azamacrocycles To: chemistry@www.ccl.net Date: Thu, 23 Jan 1997 10:59:53 -0700 (GMT+7) Content-Type: text Dear CCL readers, I am in desperate need of your helps about finding literatures relevant to the conformations and geometry of azamacrocycles. I have done survey on the crown ethers and there are quite a lot of both experimental and theoretical data, especially on 18C6. However, for azamacrocycle such as 12-ane-N4, 13-ane-N4, 14-ane-N4 until 18-ane-N6, I still can't trace back to the crystal coordinates of such macrocycles. It seems to me that people like ether linkages more than other heteroatoms. If somebody on the net has clues or knows the references on the coordinates of this serie of macrocycles, I would appreciate your helps. thank you very much, Teerakiat ---------------------------------------------------------------------------- Teerakiat Kerdcharoen, Ph.D. Address: Department of Physics, Mahidol University, Bangkok 10400 Phone: 2461381 FAX 2461381 E-mail: noy@einstein.sc.mahidol.ac.th, noy@atc.atccu.chula.ac.th Homepage: http://www.sc.mahidol.ac.th/noy/ Research: Computer Aided Molecular Design (CAMD) -----------------------------------------------------------------------------