From chd00@cc.keele.ac.uk Fri Aug 30 08:20:53 1996 Received: from gabriel.keele.ac.uk for chd00@cc.keele.ac.uk by www.ccl.net (8.7.5/950822.1) id HAA12721; Fri, 30 Aug 1996 07:47:56 -0400 (EDT) Received: from potter.cc.keele.ac.uk by gabriel.keele.ac.uk with SMTP (PP); Fri, 30 Aug 1996 12:47:54 +0100 From: "Ratty" Message-Id: <26259.199608301147@potter.cc.keele.ac.uk> Subject: MOPAC dummy atoms To: chemistry@www.ccl.net (chemmail) Date: Fri, 30 Aug 1996 12:47:47 +0100 (BST) X-Mailer: ELM [version 2.4 PL23] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit I am trying to model the effects of Methyl groups on a molecule using mopac, by comparing whole molecules with those with certain methyl groups missing. I already have z-matrices for the complete molecule, however I am having problems with removing methyl groups. The way I am doing this is 'commenting out' the relevent methyl groups as follows. M-CH3 becomes M-HX3 where X refers to a dummy atom. On substution the M-C distance is 1.5 A and the M-H distance is 1.1 A the bond angles and dihedral angles remain the same This however doesn't appear to work. The hydrogens that replace the methyl carbons do not appear in the 'right' place. When running the job in mopac it complains that atoms are too close to each other or in straight lines. Also when examing the file using RasMol it appears that the hydrogens are in the same position as the atom they are supposed to be bonded to (i.e. the bond length is 0 not 1.1 A as specified) Does anyone know what I might be doing wrong, Cheers Ratty From huang@nissan.wavefun.com Fri Aug 30 11:20:57 1996 Received: from volvo.wavefun.com for huang@nissan.wavefun.com by www.ccl.net (8.7.5/950822.1) id LAA13678; Fri, 30 Aug 1996 11:02:12 -0400 (EDT) Received: by volvo.wavefun.com (931110.SGI/930416.SGI) for chemistry@www.ccl.net id AA29274; Fri, 30 Aug 96 08:03:26 -0700 Received: from nissan.wavefun.com(198.147.95.2) by volvo.wavefun.com via smap (V1.3) id sma029271; Fri Aug 30 08:03:24 1996 Received: by nissan.wavefun.com (931110.SGI/940406.SGI.AUTO) for @volvo.wavefun.com:orcaro@lux.levels.unisa.edu.au id AA21374; Fri, 30 Aug 96 08:01:32 -0700 From: "Wayne Huang" Message-Id: <9608300801.ZM21372@nissan.wavefun.com> Date: Fri, 30 Aug 1996 08:01:23 -0700 In-Reply-To: orcaro@lux.levels.unisa.edu.au (orcaro) "CCL:M:Parameters for Cu" (Aug 30, 11:12am) References: <199608300142.LAA21086@lux.levels.unisa.edu.au> Reply-To: huang@wavefun.com X-Mailer: Z-Mail (3.2.2 10apr95 MediaMail) To: chemistry@www.ccl.net (Comp Chem List), orcaro@lux.levels.unisa.edu.au (orcaro) Subject: Re: CCL:M:Parameters for Cu Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii On Aug 30, 11:12am, orcaro wrote: > Subject: CCL:M:Parameters for Cu > Hi all. > > Does anyone know whether copper has been parameterised for > MOPAC93 (AM1 or PM3)? > > Thanks. > > * Anthony O'Dea * > * orcaro@lux.levels.unisa.edu.au * > * South Australian Surface Technology Centre * > * Ian Wark Research Institute * > * University of South Australia * > Spartan's PM3(tm) has copper parameters built-in, with facus on obtaining geometry and reproducing X-ray structure. I will be more than happy to run a test case for you. Have a good one! --Wayne -- +---------------------------------------------------------------------+ | Wayne Huang, Ph.D. | 18401 Von Karman, Suite 370 | | Computational Chemist | Irvine, California 92715 | | Wavefunction, Inc. | (714)955-2120 Fax: (714)955-2118 | | huang@wavefun.com | World Wide Web: http://wavefun.com | +---------------------------------------------------------------------+ From Alan.Shusterman@directory.Reed.EDU Fri Aug 30 12:20:55 1996 Received: from reed.edu for Alan.Shusterman@directory.Reed.EDU by www.ccl.net (8.7.5/950822.1) id MAA13877; Fri, 30 Aug 1996 12:17:38 -0400 (EDT) Received: from isis.Reed.EDU [134.10.2.1 no identification] by reed.edu (/\oo/\ Smail3.1.29.1osf1 #29.2) id ; Fri, 30 Aug 96 09:17 PDT Message-id: <1606647@isis.Reed.EDU> Date: 30 Aug 96 09:17:36 PDT From: Alan.Shusterman@directory.Reed.EDU (Alan Shusterman) Subject: Re: CCL:How can one get the chiral form of [5]Helicene, when using Spartan? To: omer@eeyore.cm.utexas.edu, CHEMISTRY@www.ccl.net --- You wrote: Question: How can one get the chiral form of the [5] Helicene, When using Spartan? --- end of quoted material --- A small trick is involved. Select the Naphthyl fragment from Rings in the builder. Put the fragment in the builder window, and then click on the 1-position to make 1,1'-binaphthyl (note: make sure the little circle on the Naphthyl fragment is also on the 1-position). Then press space bar and the middle mouse button to do an internal rotation (this makes the binaphthyl nonplanar). Finally, add two aromatic C fragments to make the "middle" benzene ring. Minimize and you should get C2-symmetry (chiral) [5]helicene. You may be interested in the following paper: RH Janke, et al, "Racemization Barriers of Helicenes: A Computational Study" JACS, 118(25), 6031 (1996). Alan Shusterman Department of Chemistry Reed College Portland, OR 97202 From echamot@xnet.com Fri Aug 30 12:22:59 1996 Received: from mail.xnet.com for echamot@xnet.com by www.ccl.net (8.7.5/950822.1) id LAA13805; Fri, 30 Aug 1996 11:39:25 -0400 (EDT) Received: from echamot.xnet.com by mail.xnet.com (8.7.5/XNet-2.1R) with SMTP id KAA15547; Fri, 30 Aug 1996 10:38:02 -0500 (CDT) Message-ID: Date: Fri, 30 Aug 96 10:37:38 EDT From: "Ernest Chamot" Subject: Re: CCL:MP4 || MP2 To: "A J Turner" , "C F Rodriquez" , chemistry@www.ccl.net X-Mailer: VersaTerm Link v1.1.6 Hi Alex, I don't have a reference supporting your particular application: >I have heard that it is 'OK' to use MP4 energyies from MP2 structures - IE >MP4 energy hyper-planes are parrallel to MP2 ones. > >Does anyone know of a good paper to support this idea. . . But your observation: >. . . would that not >suggest that mp2 energy differences are better than MP2 energies? is absolutely correct, and important to remember in the general case, not only for MP2 etc. With few exceptions, systematic errors tend to cancel within a given method, so that energy differences have less error than absolute energies. This is true for correlated and uncorrelated HF, DFT, and semiempirical methods. One "difference" that this isn't as useful for, is activation energies with semiempirical methods. Here you are looking at the difference between a ground state and an excited state, so the errors aren't all systematic: they tend to be different for excited state molecules than for ground state molecules in semiempirical parameterizations. Even here, though, if you look at RELATIVE activation barriers (ie. the difference between energy differences) you again get better accuracy due to cancellation of systematic errors. The use of isodesmic reactions to improve accuracy when calculating thermodynamic data relies on this type of cancellation: when you are comparing systems that are similar (in this case matching the bonding to define similarity) systematic errors tend to cancel. In the case of the shape of a potential surface, you are comparing VERY similar systems (ie. the same molecule in different geometries) within any local region. So, unless you are mapping the surface all the way from a ground state to a transition state, you get very good cancellation, and therefore very parallel surfaces. To my mind, this is sort of what's behind G2 theory (much discussed on the CCL since you posted your note, I see): you know the calculations you can afford to do are going to be offset from the "truth", but to the extent that different calculations (size of basis set, and degree of correlation) systematically differ from the "truth," you can use them to estimate the "true" energy. EC --- Chamot Laboratories, Inc. 530 E. Hillside Rd. Naperville, Illinois 60540 Phone/Fax: (630) 637-1559 echamot@xnet.com http://www.xnet.com/~chamotlb From chemtw@showme.missouri.edu Fri Aug 30 13:21:03 1996 Received: from mail.missouri.edu for chemtw@showme.missouri.edu by www.ccl.net (8.7.5/950822.1) id MAA14027; Fri, 30 Aug 1996 12:44:46 -0400 (EDT) Received: from black.missouri.edu (black.missouri.edu [128.206.2.222]) by mail.missouri.edu (8.7.3/8.7.3) with ESMTP id LAA72978 for ; Fri, 30 Aug 1996 11:44:46 -0500 Received: from localhost (chemtw@localhost) by black.missouri.edu (8.7.3/8.7.3) with SMTP id LAA75118 for ; Fri, 30 Aug 1996 11:44:46 -0500 X-Authentication-Warning: black.missouri.edu: chemtw owned process doing -bs Date: Fri, 30 Aug 1996 11:44:45 -0500 (CDT) From: Troy Wymore X-Sender: chemtw@black.missouri.edu To: chemistry@www.ccl.net Subject: NMR psuedo atoms in CHARMM Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII I am trying to add nmr psuedo atoms to my peptide in order to minimize the structure using NOE constraints. So far I have added the psuedo atoms, in the correct positions, to the psf. My thinking then was to add bonds (patch) from the psuedo atom to the respective hydrogens that define where each pseudo atom is placed. Then using SHAKE on all bonds to hydrogen; when the psuedo atom moved, the hydrogens would move with it. My question is this: To make the bonds to do this, am I going to have to modify the rtf (residue topology file)? Am I going about this wrong and is there an easier way to do this? Troy Wymore e-mail: chemtw@showme.missouri.edu From huang@nissan.wavefun.com Fri Aug 30 13:27:56 1996 Received: from volvo.wavefun.com for huang@nissan.wavefun.com by www.ccl.net (8.7.5/950822.1) id NAA14107; Fri, 30 Aug 1996 13:06:45 -0400 (EDT) Received: by volvo.wavefun.com (931110.SGI/930416.SGI) for CHEMISTRY@www.ccl.net id AA00028; Fri, 30 Aug 96 10:08:01 -0700 Received: from nissan.wavefun.com(198.147.95.2) by volvo.wavefun.com via smap (V1.3) id sma000026; Fri Aug 30 10:07:53 1996 Received: by nissan.wavefun.com (931110.SGI/940406.SGI.AUTO) for @volvo.wavefun.com:CHEMISTRY@www.ccl.net id AA22031; Fri, 30 Aug 96 10:06:01 -0700 From: "Wayne Huang" Message-Id: <9608301005.ZM22029@nissan.wavefun.com> Date: Fri, 30 Aug 1996 10:05:52 -0700 In-Reply-To: Omer Katzenelson "CCL:How can one get the chiral form of [5]Helicene, when using Spartan?" (Aug 29, 5:37pm) References: Reply-To: huang@wavefun.com X-Mailer: Z-Mail (3.2.2 10apr95 MediaMail) To: Omer Katzenelson Subject: Re: CCL:How can one get the chiral form of [5]Helicene, when using Spartan? Cc: CHEMISTRY@www.ccl.net Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="PART-BOUNDARY=.19608301005.ZM22029.wavefun.com" -- --PART-BOUNDARY=.19608301005.ZM22029.wavefun.com Content-Type: text/plain; charset=us-ascii On Aug 29, 5:37pm, Omer Katzenelson wrote: > Subject: CCL:How can one get the chiral form of [5]Helicene, when using Sp > Dear CCLers, > > [5] Helicene has a helical structure made up of 5 ortho-condensed > aromatic rings, and was found to be chiral. Depending on the temperature > racemization occurs. > I was calculating the structure of [5] Helicene in Spartan using various > models: AM1, Sybyl, etc. All of these structure had a C2v point group > symmetry, which means that the structure is a-chiral. > Question: How can one get the chiral form of the [5] Helicene, When using > Spartan? Omer, I have 9-helicene structures with both chiral forms (left- and right-handed), which have been optimized by AM1. The chiral structure was generated from its counter-part by symmetry operation with XZ plane reflection. Both have C2 symmetry. I have merged these two together. You should be able to build any chiral helicene by manipulating this template. The input file is attached. Use Import feature to open it with Spartan. Have fun! --Wayne -- +---------------------------------------------------------------------+ | Wayne Huang, Ph.D. | 18401 Von Karman, Suite 370 | | Computational Chemist | Irvine, California 92715 | | Wavefunction, Inc. | (714)955-2120 Fax: (714)955-2118 | | huang@wavefun.com | World Wide Web: http://wavefun.com | +---------------------------------------------------------------------+ --PART-BOUNDARY=.19608301005.ZM22029.wavefun.com X-Zm-Content-Name: input Content-Description: Text Content-Type: text/plain ; name="input" ; charset=us-ascii AM1 OPT Chiral 9-helicene structure 0 1 1 1.074571013 12.378871918 0.354416996 6 1.344658732 11.313071251 0.312904656 1 3.415607929 11.607824326 0.818288088 6 2.625231743 10.897450447 0.533199549 6 0.612907767 8.977306366 0.064763427 6 2.975026369 9.527014732 0.352405518 6 0.313987732 10.359113693 0.066291735 6 1.998730063 8.596376419 -0.071275987 6 4.310030937 9.094069481 0.608663440 6 -1.018278360 10.801406860 -0.188247338 6 0.868165433 7.070253849 -2.573396206 6 -0.491448194 8.057345390 0.197852433 6 4.647901535 7.783419609 0.442380637 1 5.039278984 9.830986977 0.976633251 1 5.640694141 7.407610893 0.731839478 6 3.727969885 6.876674652 -0.163909525 6 4.089210510 5.510530949 -0.342011392 6 2.465238810 7.338837147 -0.604761124 6 3.248797655 4.658549786 -0.999333620 1 5.041856289 5.159195900 0.081462994 1 3.470214605 3.583462238 -1.073565245 6 2.094184875 5.166082382 -1.661836028 6 1.292562366 4.282688141 -2.452418327 6 1.774032354 6.537084579 -1.581722140 6 -2.595361471 6.230172157 -0.236401945 6 -0.419714093 6.744327068 0.785951614 6 -1.760046005 8.499480247 -0.246681929 6 -2.797903776 7.555770397 -0.493313402 6 -1.415895939 5.807482719 0.441701323 6 0.530875623 6.363833427 1.805699468 6 -2.006173372 9.892987251 -0.430004388 1 -3.747625351 7.917087555 -0.914952219 6 -1.275457144 4.433709621 0.817238271 1 -3.352534533 5.476280689 -0.498480886 1 -1.214743614 11.883316994 -0.221773043 1 -3.015588522 10.212047577 -0.729898095 6 2.323687315 5.559823513 3.839003086 6 0.633819699 5.002697945 2.189162493 6 1.288176894 7.314165115 2.534725904 6 2.162646055 6.923360348 3.526830196 6 1.564687729 4.615666866 3.183032751 6 -0.255827725 4.034807682 1.623620868 1 1.159378648 8.386232376 2.317704678 1 2.737838268 7.676791668 4.084859371 1 1.656844258 3.548492908 3.434548855 1 3.042804003 5.261397839 4.615293503 6 -0.874919116 8.044023514 -4.575484753 6 0.794357717 8.453250885 -2.873372555 6 0.105665915 6.179781437 -3.370882273 6 -0.789413035 6.688990116 -4.342286587 6 -0.055111472 8.929401398 -3.849783897 1 1.443504572 9.157564163 -2.329712868 6 0.298076212 4.767425060 -3.243017673 1 -1.401655316 5.980681419 -4.920276165 1 -0.094206288 10.006113052 -4.071288109 1 -1.565274358 8.440636635 -5.333720207 1 1.504181743 3.204073906 -2.398009539 1 -2.013802528 3.714172363 0.432187378 1 -0.117557824 2.976899147 1.892080188 1 -0.346732825 4.096096516 -3.829447031 1 -1.008600593 -7.885177135 -0.743904114 6 -1.296118617 -6.823998451 -0.701074123 1 -3.382215738 -7.161512852 -1.107768655 6 -2.592869759 -6.433920860 -0.866637707 6 -0.596992493 -4.472844601 -0.510988414 6 -2.959249020 -5.068047523 -0.684175551 6 -0.273021400 -5.848994255 -0.511930227 6 -1.981935859 -4.115353107 -0.315421581 6 -4.312328815 -4.662028790 -0.883342803 6 1.077417254 -6.264426708 -0.314257443 6 -0.766512334 -2.541282177 2.116218328 6 0.482969671 -3.534756422 -0.704156280 6 -4.666359901 -3.355876923 -0.715304077 1 -5.043920040 -5.415988922 -1.209794641 1 -5.678107262 -3.001211166 -0.962754607 6 -3.736554146 -2.426038742 -0.161308795 6 -4.114409447 -1.064691544 0.019034149 6 -2.446682692 -2.860499382 0.225868076 6 -3.260683298 -0.190461308 0.628222644 1 -5.091734409 -0.735273480 -0.363873065 1 -3.498265266 0.881241798 0.701404989 6 -2.067829609 -0.669742584 1.242238045 6 -1.247334003 0.236688524 1.985994339 6 -1.726443291 -2.035588026 1.161711097 6 2.570476770 -1.665368199 -0.385892957 6 0.360223055 -2.229899168 -1.301905990 6 1.778499961 -3.949047089 -0.313777506 6 2.808964968 -2.984159470 -0.124838896 6 1.353652000 -1.271531701 -1.013472438 6 -0.642843902 -1.877963781 -2.280822039 6 2.058408260 -5.335773468 -0.127528667 1 3.783469677 -3.323631048 0.256472379 6 1.170880795 0.095211186 -1.396370411 1 3.324805737 -0.895122170 -0.166672349 1 1.295129657 -7.342193604 -0.278585762 1 3.086189508 -5.633287907 0.128994450 6 -2.541252136 -1.129064798 -4.237889290 6 -0.788295269 -0.523271441 -2.673227787 6 -1.415023446 -2.849833250 -2.964432240 6 -2.340988874 -2.485913038 -3.919337034 6 -1.770602107 -0.164156184 -3.627267838 6 0.108272158 0.466699034 -2.159178734 1 -1.256689072 -3.916919947 -2.742464066 1 -2.927095175 -3.255744219 -4.442539215 1 -1.893826008 0.898310602 -3.885324478 1 -3.300484896 -0.852299988 -4.983394623 6 1.083933234 -3.461144447 4.046145916 6 -0.653575122 -3.919288397 2.426794291 6 0.015092610 -1.628398776 2.868593931 6 0.962880194 -2.110558271 3.803101063 6 0.248277441 -4.369159222 3.368054628 1 -1.313795328 -4.641179085 1.920832157 6 -0.208976671 -0.221242979 2.735080004 1 1.587736487 -1.384951472 4.345007896 1 0.317308038 -5.442450047 3.598667383 1 1.815424919 -3.836792707 4.775953770 1 -1.481076002 1.310654163 1.930192590 1 1.912659764 0.832148790 -1.053094149 1 -0.061612576 1.518885136 -2.431946754 1 0.449474514 0.468070835 3.284305096 ENDCART FROZEN ENDFROZEN PI ENDPI PAIRING ENDPAIR HESSIAN 13 3 13 3 3 3 3 3 3 3 3 3 3 13 13 3 3 3 3 13 13 3 3 3 3 3 3 3 3 3 3 13 3 13 13 13 3 3 3 3 3 3 13 13 13 13 3 3 3 3 3 13 3 13 13 13 13 13 13 13 13 3 13 3 3 3 3 3 3 3 3 3 3 13 13 3 3 3 3 13 13 3 3 3 3 3 3 3 3 3 3 13 3 13 13 13 3 3 3 3 3 3 13 13 13 13 3 3 3 3 3 13 3 13 13 13 13 13 13 13 1 2 1 2 4 5 2 7 5 4 6 5 6 8 5 5 7 5 5 8 5 6 9 5 8 18 5 9 13 5 16 18 5 17 19 5 19 22 5 22 24 5 18 24 5 16 17 5 13 16 5 3 4 1 5 12 5 7 10 5 9 14 1 11 24 5 13 15 1 19 21 1 22 23 5 17 20 1 12 27 5 27 28 5 25 28 5 25 29 5 26 29 5 12 26 5 28 32 1 29 33 5 25 34 1 26 30 5 27 31 5 10 35 1 31 36 1 10 31 5 30 39 5 39 40 5 37 40 5 37 41 5 38 41 5 30 38 5 40 44 1 41 45 1 37 46 1 38 42 5 39 43 1 11 49 5 49 50 5 47 50 5 47 51 5 48 51 5 11 48 5 50 54 1 51 55 1 47 56 1 48 52 1 49 53 5 33 42 5 33 58 1 42 59 1 53 23 5 23 57 1 53 60 1 61 62 1 62 64 5 62 67 5 64 66 5 66 68 5 65 67 5 65 68 5 66 69 5 68 78 5 69 73 5 76 78 5 77 79 5 79 82 5 82 84 5 78 84 5 76 77 5 73 76 5 63 64 1 65 72 5 67 70 5 69 74 1 71 84 5 73 75 1 79 81 1 82 83 5 77 80 1 72 87 5 87 88 5 85 88 5 85 89 5 86 89 5 72 86 5 88 92 1 89 93 5 85 94 1 86 90 5 87 91 5 70 95 1 91 96 1 70 91 5 90 99 5 99 100 5 97 100 5 97 101 5 98 101 5 90 98 5 100 104 1 101 105 1 97 106 1 98 102 5 99 103 1 71 109 5 109 110 5 107 110 5 107 111 5 108 111 5 71 108 5 110 114 1 111 115 1 107 116 1 108 112 1 109 113 5 93 102 5 93 118 1 102 119 1 113 83 5 83 117 1 113 120 1 ENDHESS --PART-BOUNDARY=.19608301005.ZM22029.wavefun.com-- From owner-chemistry@ccl.net Fri Aug 30 15:52:08 1996 Received: from bedrock.ccl.net for owner-chemistry@ccl.net by www.ccl.net (8.7.5/950822.1) id PAA14927; Fri, 30 Aug 1996 15:41:04 -0400 (EDT) Received: from kodakr.kodak.com for lrbu00@xd88.kodak.com by bedrock.ccl.net (8.7.5/950822.1) id PAA06072; Fri, 30 Aug 1996 15:41:01 -0400 (EDT) From: Received: from euler.kodak.com by kodakr.kodak.com with SMTP id AA21034 (5.67b/IDA-1.5 for <@kodakr.kodak.com:chemistry@ccl.net>); Fri, 30 Aug 1996 15:40:28 -0400 Received: from xd88.kodak.com by euler.kodak.com via SMTP (940816.SGI.8.6.9/940406.SGI) id PAA09318; Fri, 30 Aug 1996 15:40:31 -0400 Received: by xd88.kodak.com (AIX 3.2/UCB 5.64/4.03) id AA16230; Fri, 30 Aug 1996 15:40:30 -0400 Date: Fri, 30 Aug 1996 15:40:30 -0400 Message-Id: <9608301540.ZM12132@xd88.kodak.com> X-Mailer: Z-Mail (3.0.0 15dec93) To: chemistry@ccl.net Subject: Kekule structures Cc: mckelvey@kodakr.kodak.com Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 Netters: I am wondering if there is a good program that will draw reliable Kekule structures for conjugated systems of a given connectivity and given atomic hybridisations... Will gladly share any info rec'd! Thanks! John -- John M. McKelvey email: mckelvey@Kodak.COM Computational Science Laboratory phone: (716) 477-3335 2nd Floor, Bldg 83, RL Eastman Kodak Company Rochester, NY 14650-2216 -- From owner-chemistry@ccl.net Fri Aug 30 17:52:05 1996 Received: from bedrock.ccl.net for owner-chemistry@ccl.net by www.ccl.net (8.7.5/950822.1) id RAA00676; Fri, 30 Aug 1996 17:29:12 -0400 (EDT) Received: from camsoft.com for jsb2@camsoft.com by bedrock.ccl.net (8.7.5/950822.1) id RAA08435; Fri, 30 Aug 1996 17:29:12 -0400 (EDT) From: Date: Fri, 30 Aug 96 17:29:10 EDT Received: by camsoft.com (4.1/3.1.090690-Cambridge Scientific Computing) id AA00368; Fri, 30 Aug 96 17:29:10 EDT Message-Id: <9608302129.AA00368@camsoft.com> To: chemistry@ccl.net, lrbu00@xd88.kodak.com Subject: Re: CCL:Kekule structures Cc: mckelvey@kodakr.kodak.com >I am wondering if there is a good program that will draw reliable Kekule >structures for conjugated systems of a given connectivity and given atomic >hybridisations... CS Chem3D Pro will do this. More information (and demo versions) are available from http://www.camsoft.com, info@camsoft.com, or on CD-ROM from 800-315-7300. Jonathan Brecher CambridgeSoft Corporation jsb@camsoft.com