From chemistry-request@server.ccl.net Tue Feb 19 18:57:21 2002 Received: from canter-n-siegel.schrodinger.com ([192.156.98.248]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1JNvK502076 for ; Tue, 19 Feb 2002 18:57:21 -0500 Received: (from announce@localhost) by canter-n-siegel.schrodinger.com (8.8.5/8.8.5) id PAA17780 for chemistry@ccl.net; Tue, 19 Feb 2002 15:56:49 -0800 Message-Id: <200202192356.PAA17780@canter-n-siegel.schrodinger.com> Subject: ANNC: Mopac 2002 now available from Schrodinger To: chemistry@ccl.net Date: Tue, 19 Feb 2002 15:56:48 -0800 (PST) From: Schrodinger Announcements Reply-To: Schrodinger Information Account X-Mailer: ELM [version 2.5 PL0b2] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Schrodinger, Inc. is pleased to announce the release of Mopac 2002 for Unix (including Linux). Mopac, the most widely used semiempirical quantum mechanics program in the world, is a general-purpose package for the study of chemical properties and reactions in gas, solution or solid-state. Mopac 2002's linear scaling algorithms, including the patented MOZYME algorithm, allow it to efficiently study systems up to 20,000 atoms, making it particularly suitable for proteins and DNA. Mopac 2002 delivers increased accuracy and faster performance to a much broader range of systems. Mopac 2002 includes: * The PM5 method, which is 4 times more accurate than PM3 and AM1 * AM1-d parameters for the following transition metals: Ti, V, Fe, Cu, Mo, Pd, Ag, and Pt * All main-group elements and Zn, Cd, and Hg are available for MNDO, AM1, PM3 and PM5 * Option to use external PM3(tm) parameter sets * Linear scaling for COSMO, which facilitates solvation for large systems Solvent phase takes only 25% longer than gas-phase * More accurate and robust COSMO surface construction * Improved convergence in MOZYME through level shifting * Improved eigenvector evaluation increases speed and decreases memory requirements The advanced features of Mopac 2002 are also available on Windows and Macintosh in the CAChe package. Please visit http://www.schrodinger.com or contact info@schrodinger.com to learn more about Mopac 2002 and CAChe 5.0. The web site also has a full comparison, by element, of the PM5 method to other semiempirical parameter sets. From chemistry-request@server.ccl.net Wed Feb 20 02:36:55 2002 Received: from relay3.softcomca.com ([168.144.1.70]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1K7at514887 for ; Wed, 20 Feb 2002 02:36:55 -0500 Received: from m2w084.softcomca.com ([168.144.108.84]) by relay3.softcomca.com with Microsoft SMTPSVC(5.0.2195.2966); Wed, 20 Feb 2002 02:36:34 -0500 X-Originating-IP: 202.185.72.119 X-URL: http://www.mail2web.com/ Subject: starting structure for docking Sender: "nepenthes@vplaces.net" From: "nepenthes@vplaces.net" Date: Wed, 20 Feb 2002 02:34:25 -0500 To: "chemistry@ccl.net" Reply-To: nepenthes@vplaces.net X-Priority: 3 X-MSMail-Priority: Normal MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" X-Mailer: JMail 3.7.0 by Dimac (www.dimac.net) Message-ID: X-OriginalArrivalTime: 20 Feb 2002 07:36:34.0238 (UTC) FILETIME=[5248FDE0:01C1B9E1] Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from Quoted-Printable to 8bit by server.ccl.net id g1K7at514888 Dear CCLers, I hope you will bear with this question of mine but I wasn't able to agree with my colleague about it. I've docking a molecule, citrulline, to a protein and I obtained the citrulline molecule from a protein-citrulline complex from the PDB database website. I think it's suitable by just extracting the citrulline sequence and adding hydrogen to it and minimized the structure later on before I start my docking process. My colleague, however, doesn't think it's an appropriate way of getting a starting structure for docking and I should use a structure from a molecule database (i.e. the cambridge crystallographic database or etc). He says that maybe the starting structure I have used may not be correct in terms of bond lengths/angle or the torsions. I don't think that is the case, since I minimized the structure anyway, so it wouldn't be any major difference if i take it from a complex structure or if I build the structure from scratch (like using the Biopolymer module from InsightII) or if I obtained it as a single molecule from a database. I'm do apologize if this sounds very trivial but I would be grateful for some clarification as I know most of you will have experience in such matters. Thank you for your time. Rowyna K. -------------------------------------------------------------------- mail2web - Check your email from the web at http://mail2web.com/ . From chemistry-request@server.ccl.net Wed Feb 20 02:36:55 2002 Received: from relay3.softcomca.com ([168.144.1.70]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1K7aO514883 for ; Wed, 20 Feb 2002 02:36:55 -0500 Received: from m2w092.softcomca.com ([168.144.108.92]) by relay3.softcomca.com with Microsoft SMTPSVC(5.0.2195.2966); Wed, 20 Feb 2002 02:36:12 -0500 X-Originating-IP: 202.185.72.119 X-URL: http://www.mail2web.com/ Subject: starting structure for docking Sender: "nepenthes@vplaces.net" From: "nepenthes@vplaces.net" Date: Wed, 20 Feb 2002 02:35:59 -0500 To: "chemistry@ccl.net" Reply-To: nepenthes@vplaces.net X-Priority: 3 X-MSMail-Priority: Normal MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" X-Mailer: JMail 3.7.0 by Dimac (www.dimac.net) Message-ID: X-OriginalArrivalTime: 20 Feb 2002 07:36:13.0117 (UTC) FILETIME=[45B22ED0:01C1B9E1] Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from Quoted-Printable to 8bit by server.ccl.net id g1K7at514886 Dear CCLers, I hope you will bear with this question of mine but I wasn't able to agree with my colleague about it. I've docking a molecule, citrulline, to a protein and I obtained the citrulline molecule from a protein-citrulline complex from the PDB database website. I think it's suitable by just extracting the citrulline sequence and adding hydrogen to it and minimized the structure later on before I start my docking process. My colleague, however, doesn't think it's an appropriate way of getting a starting structure for docking and I should use a structure from a molecule database (i.e. the cambridge crystallographic database or etc). He says that maybe the starting structure I have used may not be correct in terms of bond lengths/angle or the torsions. I don't think that is the case, since I minimized the structure anyway, so it wouldn't be any major difference if i take it from a complex structure or if I build the structure from scratch (like using the Biopolymer module from InsightII) or if I obtained it as a single molecule from a database. I'm do apologize if this sounds very trivial but I would be grateful for some clarification as I know most of you will have experience in such matters. Thank you for your time. Rowyna K. -------------------------------------------------------------------- mail2web - Check your email from the web at http://mail2web.com/ . From chemistry-request@server.ccl.net Wed Feb 20 04:05:58 2002 Received: from uni-freiburg.de ([132.230.2.65]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1K95v518000 for ; Wed, 20 Feb 2002 04:05:57 -0500 Received: from [132.230.171.109] (account oliver.hucke@physchem.uni-freiburg.de HELO physchem.uni-freiburg.de) by uni-freiburg.de (CommuniGate Pro SMTP 3.4.7) with ESMTP-TLS id 5045293 for chemistry@ccl.net; Wed, 20 Feb 2002 10:05:36 +0100 Message-ID: <3C73681C.6CC8F5EE@physchem.uni-freiburg.de> Date: Wed, 20 Feb 2002 10:10:52 +0100 From: Oliver Hucke X-Mailer: Mozilla 4.79 [en] (WinNT; U) X-Accept-Language: en MIME-Version: 1.0 To: chemistry@ccl.net Subject: QXP program for drug design Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Dear CCL'ers, we are interested in methods for ligand docking calculations and structure based drug design in general. We have used mainly the ligand docking program FlexX so far, but we would like to be able to treat the binding site as conformationally flexible - FlexX uses a rigid binding pocket. Somebody pointed us to the package QXP, but there is only very few information about it on the internet. Therefore, we would like to ask you for some information about QXP. Do you have any experience with QXP, especially with its ability to perform ligand docking calculations with flexible protein binding site and with the accuracy of predicted binding free energies? Could you point us to some papers describing QXP applications or other sources of information about the program? Thank you very much in advance, Oliver -- ____________________________________________________________________________ Oliver Hucke Inst. fuer Physikalische Chemie II Universitaet Freiburg Albertstr. 23a D-79104 Freiburg Tel. : +49-761-203-5130 (/-6179) Fax. : +49-761-203-6189 email: Oliver.Hucke@physchem.uni-freiburg.de ____________________________________________________________________________ From chemistry-request@server.ccl.net Wed Feb 20 04:37:48 2002 Received: from mx04.nexgo.de ([151.189.8.80]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1K9bj518854 for ; Wed, 20 Feb 2002 04:37:46 -0500 Received: from [192.168.1.1] (dialin-212-144-143-251.arcor-ip.net [212.144.143.251]) by mx04.nexgo.de (Postfix) with ESMTP id 19E9037C06; Wed, 20 Feb 2002 10:37:06 +0100 (CET) Mime-Version: 1.0 X-Sender: (Unverified) Message-Id: In-Reply-To: References: Date: Wed, 20 Feb 2002 10:37:06 +0100 To: "nepenthes@vplaces.net" From: Thomas =?iso-8859-1?Q?H=FCbner?= Subject: Re: CCL:starting structure for docking Cc: chemistry@ccl.net Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by server.ccl.net id g1K9bm518857 Dear Rowyna, in principle your approach to take the the structure from a complex, minimize it and start your docking calculations is justifiable. Of course by using this structure and its conformation you introduce a bias, that maybe useful or dangerous, depending on the docking algorithm and the protein, which you are going to dock into. The concerns of your colleague are legitimate as well. Even if the minimization may take care of any strange bond lengths, angles and torsions, the ligand structures that you extract from protein complexes out of PDB may be too distorted for the modelling program to even extract the correct covalent structure in the first place. In that case a pure molecular mechanics minimization would not help. So in practice it is often more convenient and saver to start with a molecule builder from scratch, and, if you would like to introduce the conformational bias that I mentioned above, force it onto the conformation of the bound ligand. Yours Thomas >Dear CCLers, > >I hope you will bear with this question of mine but I wasn't able to agree with my colleague about it. I've docking a molecule, citrulline, to a protein and I obtained the citrulline molecule from a protein-citrulline complex from the PDB database website. I think it's suitable by just extracting the citrulline sequence and adding hydrogen to it and minimized the structure later on before I start my docking process. >My colleague, however, doesn't think it's an appropriate way of getting a starting structure for docking and I should use a structure from a molecule database (i.e. the cambridge crystallographic database or etc). He says that maybe the starting structure I have used may not be correct in terms of bond lengths/angle or the torsions. I don't think that is the case, since I minimized the structure anyway, so it wouldn't be any major difference if i take it from a complex structure or if I build the structure from scratch (like using the Biopolymer module from InsightII) or if I obtained it as a single molecule from a database. >I'm do apologize if this sounds very trivial but I would be grateful for some clarification as I know most of you will have experience in such matters. > >Thank you for your time. > >Rowyna K. > -- .. Dr. Thomas Hübner T2-Consult, München Phone: +49 (89) 21 58 16 80 Fax: +49 (89) 21 58 16 82 thuebner@t2-consult.de http://www.t2-consult.de From chemistry-request@server.ccl.net Wed Feb 20 02:27:41 2002 Received: from mail.shcnc.AC.CN ([202.127.16.28]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1K7Rd514681 for ; Wed, 20 Feb 2002 02:27:40 -0500 Received: from PC18 ([202.127.19.225]) by mail.shcnc.AC.CN (8.12.1/8.12.1) with SMTP id g1KMPfFF012541 for ; Wed, 20 Feb 2002 14:25:42 -0800 (PST) Message-Id: <200202202225.g1KMPfFF012541@mail.shcnc.AC.CN> Date: Wed, 20 Feb 2002 15:26:14 +0800 From: bxiong To: "chemistry@ccl.net" Subject: CHARMM charge parameterization question!! X-mailer: FoxMail 3.0 beta 2 [cn] Mime-Version: 1.0 Content-Type: text/plain; charset="GB2312" Content-Transfer-Encoding: 7bit Dear CCLs: I have an abnormal residue in the simulating protein. I want ask you how to calculation this residue charge for further simulation(CHARMM 19 FF). I use the G98 to calculate the ESP charge, the N terminus and C terminus block with CH3CO and NHCH3 to mimic the protein chain environment. But I found when I remove the block group, the total charge of this abnormal residue is not zero. How can I do ? any reference, articles and suggestion will be helpful? Thanks!!! Best regards! bxiong@mail.shcnc.ac.cn Xiong Bin Shanghai Institute of Materia Medica, C.A.S. phone:021-64311833-222(office) From chemistry-request@server.ccl.net Wed Feb 20 06:17:05 2002 Received: from gateway.pharmacia.com ([193.235.243.3]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1KBH5521649 for ; Wed, 20 Feb 2002 06:17:05 -0500 Received: from gateway.pharmacia.com (localhost [127.0.0.1]) by gateway.pharmacia.com (Switch-2.0.1/Switch-2.0.1) with ESMTP id g1KBFre03932 for ; Wed, 20 Feb 2002 06:15:53 -0500 (EST) Received: from uskzoms008.uskzo.am.pnu.com (uskzoms008.uskzo.am.pnu.com [146.240.201.76]) by gateway.pharmacia.com (Switch-2.0.1/Switch-2.0.1) with ESMTP id g1KBFrw03925 for ; Wed, 20 Feb 2002 06:15:53 -0500 (EST) Received: by uskzoms008.uskzo.am.pnu.com with Internet Mail Service (5.5.2653.19) id ; Wed, 20 Feb 2002 06:16:39 -0500 Received: from uskzoms008.uskzo.am.pnu.com ([146.240.201.76]) by uskzoms008.uskzo.am.pnu.com with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2653.13) id FALNLDY0; Wed, 20 Feb 2002 06:16:34 -0500 Received: from 146.240.201.75 by uskzoms008.uskzo.am.pnu.com (InterScan E-Mail VirusWall NT); Wed, 20 Feb 2002 06:16:34 -0500 Received: by uskzoms007.uskzo.am.pnu.com with Internet Mail Service (5.5.2653.19) id <1QA1KK23>; Wed, 20 Feb 2002 06:16:33 -0500 From: "STOUTEN, PIETER [R&D/0467]" To: "'Oliver Hucke'" Cc: "'Computational Chemistry List'" Message-ID: <1D9487210084054C82CADECFE16E16560369B241@itnerms020.itner.eu.pnu.com> Subject: RE: QXP program for drug design Date: Wed, 20 Feb 2002 06:16:32 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Hello Oliver, >Do you have any experience with QXP, > Yes. In fact, we think it is so good that we recently concluded a global agreement so that our research sites in St. Louis, Chicago, Kalamazoo (USA) and Nerviano (Italy) have unlimited access and can run an unlimited number of simultaneous QXP jobs. We are in fact in the process of purchasing two Linux clusters with the specific aim to run QXP on them. >especially with its ability to >perform ligand docking calculations with flexible protein binding site >and with the accuracy of predicted binding free energies? > Well, that's the holy grail, isn't it? In order to obtain correlation with experiment, one often has to scale the various energy terms and even then the results are not always satisfactory. Colin McMartin is about ready to release a new scoring function that is based both on crystal structure data and on inhibition data of congeneric sets of compounds. In terms of docking quality (i.e., the ability to reproduce known binding modes), we find that often QXP finds the correct mode (among, say, the best 10-20 poses), but does not score it highest. Both docking and scoring quality also depend to a large extent on the target under consideration. Another docking program you might consider is MolSoft's ICM, whose scoring function has been optimized such that "actives" and "inactives" are separated as much as possible. >Could you point us to some papers describing QXP applications or other >sources of information about the program? > I saw two back-to-back presentations at the 219th ACS meeting in San Francisco (March 2000), one by Dominic Ryan of SKB and one by Venkatraman Mohan of Isis Pharma. They both prominently featured application of QXP and both speakers were quite positive about their experiences. In terms of ease of use QXP/Flo surpasses anything I have seen. It is clearly designed and developed for modellers by a modeller (who got frustrated with generally available tools and decided to build his own). Hope this helps, Pieter Pieter F.W. Stouten, Ph.D. Head, Computational Sciences Department of Chemistry Pharmacia Italia, Nerviano (Mi), Italy Phone: +39-02-4838-5227 (secretary: 3962) Fax: +39-02-4838-3965 Mobile: +39-348-260-3380 From chemistry-request@server.ccl.net Wed Feb 20 06:47:56 2002 Received: from mailwall1.statoil.com ([143.97.143.27]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1KBlt522021 for ; Wed, 20 Feb 2002 06:47:55 -0500 Received: from statoil.no (mailhost.statoil.no [143.97.20.109]) by mailwall1.statoil.com (8.11.6/8.11.6) with ESMTP id g1KBlUE21705 for ; Wed, 20 Feb 2002 12:47:31 +0100 (MET) Received: from stfo-lnsmtp2.statoil.no (stfo-lnsmtp2.st.statoil.no [143.97.20.149]) by statoil.no (8.11.6/8.11.6) with SMTP id g1KBlTQ31508 for ; Wed, 20 Feb 2002 12:47:29 +0100 Received: by stfo-lnsmtp2.statoil.no(Lotus SMTP MTA v4.6.6 (890.1 7-16-1999)) id 41256B66.0040C303 ; Wed, 20 Feb 2002 12:47:22 +0100 X-Lotus-FromDomain: STATOIL@INTERNET From: =?iso-8859-1?Q?=22Jon_Andreas_St=F8vneng=22?= Sender: =?iso-8859-1?Q?=22Jon_Andreas_St=F8vneng=22?= To: chemistry@ccl.net Message-ID: <41256B66.0040B87C.00@stfo-lnsmtp2.statoil.no> Date: Wed, 20 Feb 2002 12:46:44 +0100 Subject: MP2 vs exact reaction energies Mime-Version: 1.0 Content-type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by server.ccl.net id g1KBlu522022 Dear CCL-readers, consider a chemical reaction A + B --> AB. Using MP2 with a good basis set, can any general statements be made about the calculated reaction energy E(AB)-E(A)-E(B) as compared with the exact reaction energy? For example: The reaction of 4 AlH with 4 H2AlOH resulting in (Al2H4O)4 is calculated to be exothermic by 329, 339, and 374 kcal/mol at the Hartree-Fock, BP86, and MP2 level, respectively. What, if anything, can then be said about the exact energy of this reaction? sincerely, ------------------------------------ Jon Andreas Støvneng Statoil Research Centre, N-7005 Trondheim, Norway jast@statoil.com Tel: +47 73584824 Fax: +47 73584345 ------------------------------------------------------------------- The information contained in this message may be CONFIDENTIAL and is intended for the addressee only. Any unauthorised use, dissemination of the information or copying of this message is prohibited. If you are not the addressee, please notify the sender immediately by return e-mail and delete this message. Thank you. From chemistry-request@server.ccl.net Wed Feb 20 08:41:55 2002 Received: from kula.geosc.psu.edu ([128.118.174.177]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1KDft523996 for ; Wed, 20 Feb 2002 08:41:55 -0500 Received: from [128.118.174.181] (kubicki.geosc.psu.edu [128.118.174.181]) by kula.geosc.psu.edu (8.9.3/8.9.3) with ESMTP id IAA01056 for ; Wed, 20 Feb 2002 08:41:35 -0500 (EST) Mime-Version: 1.0 Message-Id: Date: Wed, 20 Feb 2002 08:43:45 -0500 To: chemistry@ccl.net From: James Kubicki Subject: Increasing the Maximum Number of Tesserae in G98 Content-Type: text/plain; charset="us-ascii" ; format="flowed" Attempting to run a PCM calculation on a relatively large solute, I run into the following error - Too many tesserae. Increase the MxTs. I have tried a non-standard route to increase the maximum number of tesserae, but I believe that this increases the number per sphere, not the maximum number allowable. Does anyone know how to " Increase the MxTs"? Jim Kubicki -- James Kubicki Dept. of Geosciences 308 Deike Bldg. The Pennsylvania State University University Park, PA 16802 (814) 865-3951 (814) 863-8724 (Fax) From chemistry-request@server.ccl.net Wed Feb 20 09:04:03 2002 Received: from postoffice.mail.cornell.edu ([132.236.56.7]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1KE43524415 for ; Wed, 20 Feb 2002 09:04:03 -0500 Received: from cornell.edu ([128.84.182.122]) by postoffice.mail.cornell.edu (8.9.3/8.9.3) with ESMTP id JAA17755; Wed, 20 Feb 2002 09:03:41 -0500 (EST) Sender: richard@cornell.edu Message-ID: <3C73ACBD.D87F1125@cornell.edu> Date: Wed, 20 Feb 2002 09:03:41 -0500 From: Richard Gillilan X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.4.16 i686) X-Accept-Language: en MIME-Version: 1.0 To: "nepenthes@vplaces.net" CC: "chemistry@ccl.net" Subject: Re: CCL:starting structure for docking References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit "nepenthes@vplaces.net" wrote: > > Dear CCLers, > > I hope you will bear with this question of mine but I wasn't able to agree with my colleague about it. I've docking a molecule, citrulline, to a protein and I obtained the citrulline molecule from a protein-citrulline complex from the PDB database website. I think it's suitable by just extracting the citrulline sequence and adding hydrogen to it and minimized the structure later on before I start my docking process. Sounds like you are treating the citrulline as a rigid body. Looks like there are at least 5 rotatable bonds in that structure. You should really use flexible docking like Autodock. In that case the initial structure does not matter, the torsion angles will be randomized during the Monte Carlo steps and there should be no bias ... you are effectively performing minimization of the ligand during the docking process. Bond length and angle changes are probably very minor. Richard Gillilan MacCHESS From chemistry-request@server.ccl.net Wed Feb 20 12:42:07 2002 Received: from mbx.unige.ch ([129.194.8.72]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g1KHg6528745 for ; Wed, 20 Feb 2002 12:42:07 -0500 Received: from CONVERSION-DAEMON.mbx.unige.ch by mbx.unige.ch (PMDF V6.0-025 #38753) id <0GRU00L01EHLH5@mbx.unige.ch> for chemistry@ccl.net; Wed, 20 Feb 2002 18:41:45 +0100 (MET) Received: from localhost (lnx2.unige.ch [129.194.8.93]) by mbx.unige.ch (PMDF V6.0-025 #38753) with ESMTP id <0GRU00IQ0EHLUX@mbx.unige.ch> for chemistry@ccl.net; Wed, 20 Feb 2002 18:41:45 +0100 (MET) Received: from 138.37.52.177 ( [138.37.52.177]) as user boulet@mbox.unige.ch by webmail.unige.ch with HTTP; Wed, 20 Feb 2002 18:41:44 +0100 Date: Wed, 20 Feb 2002 18:41:44 +0100 From: Pascal.Boulet@chiphy.unige.ch Subject: Fwd: for ccl: Fermi and Coulomb holes X-Originating-IP: 138.37.52.177 To: chemistry@ccl.net Message-id: <1014226904.3c73dfd8ed6eb@webmail.unige.ch> MIME-version: 1.0 Content-type: text/plain; charset=iso-8859-1 Content-transfer-encoding: 8BIT User-Agent: Internet Messaging Program (IMP) 3.0 X-Comment: This message was scanned against viruses by mbx.unige.ch. Dear CCL'ers, Recently, I've been asked a question about the difference between the Coulomb hole and the Fermi hole. Could someone give me an answer? Thanks in advance, Pascal ----- Forwarded message from Stephen Stackhouse ----- Date: Wed, 20 Feb 2002 17:14:39 +0000 From: Stephen Stackhouse Reply-To: Stephen Stackhouse Subject: for ccl To: Pascal Boulet Pascal, Here is my question: I have recently been reading "A Chemist's Guide to Density Functional Theory". On page 26 of the book the authors discuss the Fermi hole in terms of pair density and state that "Usually the exchange hole is largest around the probe electron." Can anyone tell me why this is so? Why is it not largest at the reference electron, like the Coulomb hole? Stephen ----- End forwarded message -----