From chemistry-request@server.ccl.net Mon Mar 6 17:57:59 2000 Received: from ralun.usach.cl (root@ralun.usach.cl [158.170.64.21]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id RAA30559 for ; Mon, 6 Mar 2000 17:57:55 -0500 Received: from lauca.usach.cl ([158.170.51.104]) by ralun.usach.cl (8.10.0.Beta10/8.10.0.Beta10) with ESMTP id e26LpZs03625 for ; Mon, 6 Mar 2000 18:51:35 -0300 (CDT) Message-ID: <38C4374B.795A1FA@lauca.usach.cl> Date: Mon, 06 Mar 2000 18:55:07 -0400 From: danilo2 To: CCL Subject: partial optimization (x,y,z) in G98 Hi all! I trying to do a partial optimization using cartesian coordenates (x,y,z) in G98. Anybody know how can I fix some atoms during the optimization? (don't using Z-matrix) Thanks a lot for any help! Fernando Gonzalez N. University of Santiago de Chile Faculty of Chemistry and Biology. Casilla 40, Correo 33, Santiago, Chile Fono: (562) 6811542; 6811644 E-mail : fgonzale@lauca.usach.cl 6811366, Anexo:717 Fax : (562) 681 2108 Fax-Wave: 530-327-8534 ************************************************************************** From chemistry-request@server.ccl.net Tue Mar 7 03:49:20 2000 Received: from mail.zrz.tu-berlin.de (mail.zrz.TU-Berlin.DE [130.149.4.15]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id DAA00337 for ; Tue, 7 Mar 2000 03:49:14 -0500 Received: from argon.chem.tu-berlin.de ([130.149.131.31]) by mail.zrz.tu-berlin.de with smtp (exim-3.13) for id 12SEee-0005Ei-00; Tue, 07 Mar 2000 08:43:45 +0100 Received: by argon.chem.tu-berlin.de (AIX 3.2/UCB 5.64/ZRZ-AIX) id AA33314; Tue, 7 Mar 2000 08:50:59 +0100 From: Wolfram Koch Message-Id: <10003070750.AA33314@argon.chem.tu-berlin.de> Subject: commercial announcement: new book on DFT To: chemistry@ccl.net Date: Tue, 7 Mar 100 08:50:59 +0100 (NFT) X-Mailer: ELM [version 2.4 PL23] Content-Type: text Dear colleagues, those of you interested in DFT might want to learn about following new book: Koch, Wolfram / Holthausen, Max C. A Chemist's Guide to Densitiy Functional Theory 198.- DM / 101.24 EUR / 176.- SFR 2000. XIV, 294 pages. Hardcover ISBN 3-527-29918-1 Wiley-VCH, Weinheim (Germany) >From the Table of Contents: Elementary Quantum Chemistry, Electron Density and Hole Functions, The Electron Density as Basic Variable: Early Attempts, The Hohenberg-Kohn Theorems, The Kohn-Sham Approach, The Quest for Approximate Exchange-Correlation Functionals, The Basic Machinery of Density Functional Programs, Molecular Structures and Vibrational Frequencies, Relative Energies and Thermochemistry, Electric Properties, Magnetic Properties, Hydrogen Bonds and Weakly Bound Systems, Chemical Reactivity: Exploration of Potential Energy Surfaces, Bibliography, Index. >From the Foreword by Evert Jan Baerends: "It is because of the well equilibrated treatment of physical principles and chemical applications that this book does a good and very timely service to the computational and quantum chemists as well as to the chemistry community at large. I am happy to recommend it to this audience". >From comments by P. v. R. Schleyer on the back cover: "Chemists familiar with conventional quantum mechanics will applaud and benefit greatly from this particularly instructive, thorough and clearly written exposition of density functional theory: its basis, concepts, terms, implementation, and performance in diverse applications. Users of DFT for structure, energy, and molecular property computations, as well as reaction mechanism studies, are guided to the optimum choices of the most effective methods. Well done!". For further information see: http://www.wiley-vch.de/books/tis/eng/3-527-29918-1.html or contact the authors at kochw@argon.chem.tu-berlin.de or mh@qc.ag-berlin.mpg.de Cheers, Wolfram -- _________________________________________________________________________ Prof. Dr. Wolfram Koch Institut fuer Organische Chemie, Sekr.C3 Technische Universitaet Berlin Strasse des 17.Juni 135, D-10623 Berlin Fon: +49 30 314 27870, Fax: +49 30 314 21102 e-mail: kochw@argon.chem.TU-Berlin.DE _________________________________________________________________________ From chemistry-request@server.ccl.net Tue Mar 7 10:06:37 2000 Received: from kasei.materials.ox.ac.uk (kasei.materials.ox.ac.uk [163.1.64.46]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id KAA02751 for ; Tue, 7 Mar 2000 10:06:35 -0500 Received: from localhost (hfield@localhost) by kasei.materials.ox.ac.uk (8.9.3/8.9.3) with ESMTP id OAA26072 for ; Tue, 7 Mar 2000 14:00:12 GMT X-Authentication-Warning: kasei.materials.ox.ac.uk: hfield owned process doing -bs Date: Tue, 7 Mar 2000 14:00:12 +0000 (GMT) From: Andrew Horsfield X-Sender: hfield@kasei.materials.ox.ac.uk Reply-To: Andrew Horsfield To: Computational Chemistry List Subject: Lebedev again Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Hi, Having had some time to think about the Lebedev tables I received following an earlier posting, I am now struck by how wide the spacings are between different meshes. By this I mean that tables exist for (say) l = 3 (6), l = 5 (14), l = 7 (26), l = 9 (38), l = 11 (50), but then nothing more until l = 15 (86), where l is the maximum angular monetum that can be integrated, and the number in brackets is the number of points. I have checked several sources, and everyone does something similar. Is there a reason for this apart from the inconvenience of having to type in multiple tables (like you need to double the number of points to get an extra digit of accuracy)? Cheers, Andrew +----------------------------------------------------+ Andrew Horsfield e-mail: horsfield@fecit.co.uk FECIT, 2 Longwalk Road, Stockley Park, Uxbridge, Middlesex UB11 1AB, United Kingdom. phone: +44-(0)181-606-4653 FAX: +44-(0)181-606-4422 +----------------------------------------------------+ From chemistry-request@server.ccl.net Tue Mar 7 11:32:54 2000 Received: from mail.science.siu.edu (mail.science.siu.edu [131.230.107.5]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id LAA03240 for ; Tue, 7 Mar 2000 11:32:54 -0500 Received: from tapas (131.230.99.83) by mail.science.siu.edu with SMTP (Eudora Internet Mail Server 2.2); Tue, 7 Mar 2000 09:27:20 -0600 Message-ID: <002001bf8849$72561ee0$5363e683@thchem.siu.edu> From: "Tapas Kar" To: "danilo2" , "CCL" References: <38C4374B.795A1FA@lauca.usach.cl> Subject: Re: CCL:partial optimization (x,y,z) in G98 Date: Tue, 7 Mar 2000 09:26:01 -0600 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2314.1300 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2314.1300 Use opt=addredundant (G94) =Modredundant (G98) in first line and after coordinates add lines like 1 2 2.1 F this indicates freeze bond length between atom 1 and 2 at 2.1 See Gaussian98 user's reference manual page 119-120 ( 113-114 in Gaussian 94 user's reference) for more info. ---------------------------------------------------- Tapas Kar, Ph. D Department of Chemistry 1245 Lincoln Dr. # 146F Southern Illinois University Carbondale, IL 62901-4409 Tel: 618-453-6485(Off)/6433(Lab) Fax: 618-453-6408 email: tapaskar@siu.edu tapas@risky3.thchem.siu.edu ----- Original Message ----- From: danilo2 To: CCL Sent: Monday, March 06, 2000 4:55 PM Subject: CCL:partial optimization (x,y,z) in G98 > Hi all! > > I trying to do a partial optimization using cartesian coordenates > (x,y,z) in G98. > Anybody know how can I fix some atoms during the optimization? > (don't using Z-matrix) > > Thanks a lot for any help! > > > Fernando Gonzalez N. > > University of Santiago de Chile > Faculty of Chemistry and Biology. > Casilla 40, Correo 33, Santiago, Chile Fono: (562) 6811542; 6811644 > E-mail : fgonzale@lauca.usach.cl 6811366, > Anexo:717 > Fax : (562) 681 2108 Fax-Wave: 530-327-8534 > ************************************************************************** > > > > > > -= This is automatically added to each message by mailing script =- > CHEMISTRY@ccl.net -- To Everybody | CHEMISTRY-REQUEST@ccl.net -- To Admins > MAILSERV@ccl.net -- HELP CHEMISTRY or HELP SEARCH > CHEMISTRY-SEARCH@ccl.net -- archive search | Gopher: gopher.ccl.net 70 > Ftp: ftp.ccl.net | WWW: http://www.ccl.net/chemistry/ | Jan: jkl@ccl.net > > > > > From chemistry-request@server.ccl.net Tue Mar 7 12:03:43 2000 Received: from havana.ks.uiuc.edu (havana.ks.uiuc.edu [130.126.120.73]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id MAA03484 for ; Tue, 7 Mar 2000 12:03:42 -0500 Received: from bastogne.ks.uiuc.edu (bastogne.ks.uiuc.edu [130.126.120.128]) by havana.ks.uiuc.edu (8.9.1/8.9.1) with ESMTP id JAA22800 for ; Tue, 7 Mar 2000 09:58:08 -0600 (CST) Received: (from brunner@localhost) by bastogne.ks.uiuc.edu (8.9.1b+Sun/8.9.1) id JAA02080 for chemistry@ccl.net; Tue, 7 Mar 2000 09:58:09 -0600 (CST) Date: Tue, 7 Mar 2000 09:58:09 -0600 From: Robert Brunner To: chemistry@ccl.net Subject: Announce: BioCoRe Message-ID: <20000307095808.A2057@ks.uiuc.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i Hello, We have just released BioCoRe, the first version of our collaborative research environment for molecular modeling. Please try it out, and let us know if you find it useful, and what we can do to improve it. Please send feedback to collaboratory@ks.uiuc.edu. More details on BioCoRe are included below. Thanks, Robert Brunner rbrunner@uiuc.edu ------------------------------------------- Urbana, Illinois - The Theoretical Biophysics Group at the University of Illinois is proud to announce the initial public release of BioCoRE, a collaborative research environment. BioCoRE software is freely available for use at the Theoretical Biophysics Group website. BioCoRE development is supported by the NIH National Center for Research Resources. Modern computational structural biology requires scientists to employ a wide range of tools and techniques to solve complex problems while keeping accurate and complete records of research activities. Additional complications are introduced by the need to effectively engage in interdisciplinary collaborations with geographically dispersed colleagues. The software BioCoRE, a collaborative research environment for molecular modeling and simulations, addresses these challenges. Initial design work has led to a web-based architecture focused on four primary interface paradigms: + a WORKBENCH interface includes features for controlling molecular modeling, simulation, and bioinformatics tools with convenient and uniform access to collaboratory data. Initial tools in this category include the ability to start and monitor molecular dynamics simulations via a web browser interface. + a NOTEBOOK interface automates recording of research activities. Initial tools in this category include a notebook tool which can be used by researchers to engage in offline discussions as well as review and search the entire text of any prior chat session. + a CONFERENCE interface enables scientists to discuss their research across distances in real time or time-delayed sessions and will spawn software for teleconferencing and synchronized visualization of shared data at distant sites. Initially, this category includes a text-based chat mechanism where the researchers can choose topics and converse with other researchers who are working on the same project. + a DOCUMENTS interface permits the preparation of multi-author documents in a cross-platform revision control system. BioCoRE consists of html and javascript and java where needed. For additional information, please visit the BioCoRE website at . The Theoretical Biophysics group encourages BioCoRE users to be closely involved in the development process through reporting bugs, contributing fixes, periodical surveys and via other means. Questions or comments may be directed to collaboratory@ks.uiuc.edu. We are eager to hear from you, and thank you for using our software! From chemistry-request@server.ccl.net Tue Mar 7 13:05:26 2000 Received: from harfang.CC.UMontreal.CA (harfang.CC.UMontreal.CA [132.204.2.102]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id NAA03870 for ; Tue, 7 Mar 2000 13:05:26 -0500 Received: from esi21.ESI.UMontreal.CA (esi21.ESI.UMontreal.CA [132.204.2.91]) by harfang.CC.UMontreal.CA (8.8.8/8.8.8) with ESMTP id LAA18050; Tue, 7 Mar 2000 11:59:50 -0500 (EST) Received: from localhost (wangx@localhost) by esi21.ESI.UMontreal.CA with ESMTP id LAA316440 (8.8.7/IDA-1.6); Tue, 7 Mar 2000 11:59:50 -0500 (EST) X-Authentication-Warning: esi21.ESI.UMontreal.CA: wangx owned process doing -bs Date: Tue, 7 Mar 2000 11:59:49 -0500 From: Wang Xiaogang X-Sender: wangx@esi21.ESI.UMontreal.CA To: Y Z cc: CHEMISTRY@ccl.net Subject: Re: f90 and f77 differ when compiling large array ? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Dear CCLers, I just found out a solution to my question, I can use allocatable array to solve this problem in f90. use something like DOUBLE COMPLEX, allocatable::AA(:,:,:) allocate(aa(256,256,256)) Is this the only way to handle large arrays in f90? Xiaogang On Tue, 7 Mar 2000, Wang Xiaogang wrote: > Dear CCLers, > Concerning the same question asked recently on CCL (compile a large array > in fortran), I found a strange thing, > > When I use f77, the suggested prescriptions all work. (use 'common' > or 'save' or '-static' compiler option) > But when I use f90, all of them fail. I get the error message > > DOUBLE COMPLEX AA(256,256,256) > ^ > f90-1435 f90: ERROR TEST, File = fft.f, Line = 4, Column = 22 > The storage size needed for "AA" exceeds 268,435,455 bytes, the maximum > storage size available. > > f90: MIPSpro Fortran 90 Version 7.3 (f52) Tue Mar 7, 2000 11:31:58 > > > My question is why f90 compiler cannot allocate large array to data > segment while f77 compiler can? > > My stacksize limit is about 500 megabytes. > I met this problem on SGI origin 2000, irix 6.5. > > Thanks. > > Xiaogang > > On Tue, 22 Feb 2000, Y Z wrote: > > > After I asked the question for 3D-FFT, > > I got a lot of responses. Thanks a lot for > > their helps , my problem have been solved. > > > > > > Here is the summary > > > > My original question is: > > > > Hi, > > > > Are there any way to calculate a (256,256,256) order > > DOUBLE COMPLEX FFT in FORTRAN77? I tried to do the > > following subrouitine but cannot pass the compiling. > > > > > > By f77 in SGI : > > > > Warning: Stack frame size (270015328) larger than system limit (67108864) > > > > +++++++++++++++++++++++++++++++++ > > > > program test > > IMPLICIT DOUBLE PRECISION (A-H,O-Z) > > DOUBLE COMPLEX AA(256,256,256) > > DIMENSION ID(64),CC(64) > > DIMENSION NORD(3) > > DO 100 i=1,256 > > DO 100 j=1,256 > > DO 100 k=1,256 > > xx=DBLE(I+j+k) > > AA(i,j,k)=DCMPLX(xx,0.0D0) > > 100 CONTINUE > > NORD(1)=8 > > NORD(2)=8 > > NORD(3)=8 > > IERR=0 > > CALL DFFT3D(dta,NORD,ID,CC,1,IERR) > > STOP > > END > > > ------------------------------------------------ > Dr Xiaogang Wang > Departement de chimie > Universite de Montreal > C.P. 6128, succursale Centre-ville > Montreal, Quebec H3C 3J7 > > Tel. (514) 3436111 ext. 3947 (office) > FAX (514) 3437586 (office) > e-mail: wangx@magellan.umontreal.ca > http://physchem.ox.ac.uk/~xgwang/ > ------------------------------------------------ > > ------------------------------------------------ Dr Xiaogang Wang Departement de chimie Universite de Montreal C.P. 6128, succursale Centre-ville Montreal, Quebec H3C 3J7 Tel. (514) 3436111 ext. 3947 (office) FAX (514) 3437586 (office) e-mail: wangx@magellan.umontreal.ca http://physchem.ox.ac.uk/~xgwang/ ------------------------------------------------ From chemistry-request@server.ccl.net Tue Mar 7 13:30:52 2000 Received: from harfang.CC.UMontreal.CA (harfang.CC.UMontreal.CA [132.204.2.102]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id NAA04049 for ; Tue, 7 Mar 2000 13:30:52 -0500 Received: from esi21.ESI.UMontreal.CA (esi21.ESI.UMontreal.CA [132.204.2.91]) by harfang.CC.UMontreal.CA (8.8.8/8.8.8) with ESMTP id LAA16364; Tue, 7 Mar 2000 11:48:07 -0500 (EST) Received: from localhost (wangx@localhost) by esi21.ESI.UMontreal.CA with ESMTP id LAA317768 (8.8.7/IDA-1.6); Tue, 7 Mar 2000 11:48:07 -0500 (EST) X-Authentication-Warning: esi21.ESI.UMontreal.CA: wangx owned process doing -bs Date: Tue, 7 Mar 2000 11:48:06 -0500 From: Wang Xiaogang X-Sender: wangx@esi21.ESI.UMontreal.CA To: Y Z cc: CHEMISTRY@ccl.net Subject: f90 and f77 differ when compiling large array ? In-Reply-To: <20000222234220.32641.qmail@hotmail.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Dear CCLers, Concerning the same question asked recently on CCL (compile a large array in fortran), I found a strange thing, When I use f77, the suggested prescriptions all work. (use 'common' or 'save' or '-static' compiler option) But when I use f90, all of them fail. I get the error message DOUBLE COMPLEX AA(256,256,256) ^ f90-1435 f90: ERROR TEST, File = fft.f, Line = 4, Column = 22 The storage size needed for "AA" exceeds 268,435,455 bytes, the maximum storage size available. f90: MIPSpro Fortran 90 Version 7.3 (f52) Tue Mar 7, 2000 11:31:58 My question is why f90 compiler cannot allocate large array to data segment while f77 compiler can? My stacksize limit is about 500 megabytes. I met this problem on SGI origin 2000, irix 6.5. Thanks. Xiaogang On Tue, 22 Feb 2000, Y Z wrote: > After I asked the question for 3D-FFT, > I got a lot of responses. Thanks a lot for > their helps , my problem have been solved. > > > Here is the summary > > My original question is: > > Hi, > > Are there any way to calculate a (256,256,256) order > DOUBLE COMPLEX FFT in FORTRAN77? I tried to do the > following subrouitine but cannot pass the compiling. > > > By f77 in SGI : > > Warning: Stack frame size (270015328) larger than system limit (67108864) > > +++++++++++++++++++++++++++++++++ > > program test > IMPLICIT DOUBLE PRECISION (A-H,O-Z) > DOUBLE COMPLEX AA(256,256,256) > DIMENSION ID(64),CC(64) > DIMENSION NORD(3) > DO 100 i=1,256 > DO 100 j=1,256 > DO 100 k=1,256 > xx=DBLE(I+j+k) > AA(i,j,k)=DCMPLX(xx,0.0D0) > 100 CONTINUE > NORD(1)=8 > NORD(2)=8 > NORD(3)=8 > IERR=0 > CALL DFFT3D(dta,NORD,ID,CC,1,IERR) > STOP > END > ------------------------------------------------ Dr Xiaogang Wang Departement de chimie Universite de Montreal C.P. 6128, succursale Centre-ville Montreal, Quebec H3C 3J7 Tel. (514) 3436111 ext. 3947 (office) FAX (514) 3437586 (office) e-mail: wangx@magellan.umontreal.ca http://physchem.ox.ac.uk/~xgwang/ ------------------------------------------------ From chemistry-request@server.ccl.net Tue Mar 7 13:55:12 2000 Received: from sunu450.rz.ruhr-uni-bochum.de (sunu450.rz.ruhr-uni-bochum.de [134.147.64.5]) by server.ccl.net (8.8.7/8.8.7) with SMTP id NAA04214 for ; Tue, 7 Mar 2000 13:55:12 -0500 Received: (qmail 18987 invoked from network); 7 Mar 2000 17:49:36 -0000 Received: from cvw.orch.ruhr-uni-bochum.de (HELO ?134.147.110.57?) (134.147.110.57) by mailhost.rz.ruhr-uni-bochum.de with SMTP; 7 Mar 2000 17:49:36 -0000 Mime-Version: 1.0 X-Sender: wuellcbd@mailhost.rz.ruhr-uni-bochum.de Message-Id: In-Reply-To: References: Date: Tue, 7 Mar 2000 18:49:26 +0100 To: Andrew Horsfield From: Christoph van =?iso-8859-1?Q?W=FCllen?= Subject: Re: CCL:Lebedev again Cc: Chemistry@CCL.net Content-Type: text/plain; charset="us-ascii" ; format="flowed" >Hi, > >Having had some time to think about the Lebedev tables I received >following an earlier posting, I am now struck by how wide the spacings are >between different meshes. By this I mean that tables exist for (say) l = 3 >(6), l = 5 (14), l = 7 (26), l = 9 (38), l = 11 (50), but then nothing >more until l = 15 (86), where l is the maximum angular monetum that can be >integrated, and the number in brackets is the number of points. I have >checked several sources, and everyone does something similar. Is there a >reason for this apart from the inconvenience of having to type in multiple >tables (like you need to double the number of points to get an extra digit >of accuracy)? > ... Lebedev considers only grids with octahedral symmetry, so adding a grid point which is not on too many symmetry elements has many brothers and sisters on equivalent positions. Furthermore, not all grids theoretically possible are numerically useful (i.e. usually one does not want grids with negative weights). -- ---------------------------+------------------------------------------------ Christoph van Wullen | Fon (University): +49 234 32 26485 Theoretical Chemistry | Fax (University): +49 234 32 14109 Ruhr-Universitaet | Fon/Fax (private): +49 234 33 22 75 D-44780 Bochum, Germany | eMail: Christoph.van.Wuellen@Ruhr-Uni-Bochum.de ---------------------------+------------------------------------------------ From chemistry-request@server.ccl.net Tue Mar 7 13:57:50 2000 Received: from sunu450.rz.ruhr-uni-bochum.de (sunu450.rz.ruhr-uni-bochum.de [134.147.64.5]) by server.ccl.net (8.8.7/8.8.7) with SMTP id NAA04241 for ; Tue, 7 Mar 2000 13:57:49 -0500 Received: (qmail 22298 invoked from network); 7 Mar 2000 17:52:14 -0000 Received: from cvw.orch.ruhr-uni-bochum.de (HELO ?134.147.110.57?) (134.147.110.57) by mailhost.rz.ruhr-uni-bochum.de with SMTP; 7 Mar 2000 17:52:14 -0000 Mime-Version: 1.0 X-Sender: wuellcbd@mailhost.rz.ruhr-uni-bochum.de Message-Id: In-Reply-To: References: Date: Tue, 7 Mar 2000 18:52:07 +0100 To: Wang Xiaogang From: Christoph van =?iso-8859-1?Q?W=FCllen?= Subject: Re: CCL:f90 and f77 differ when compiling large array ? Cc: Chemistry@CCL.net Content-Type: text/plain; charset="us-ascii" ; format="flowed" ... if stack or data size is not sufficient this will not solve your problem but only defer it until program execution (not compilation). -- ---------------------------+------------------------------------------------ Christoph van Wullen | Fon (University): +49 234 32 26485 Theoretical Chemistry | Fax (University): +49 234 32 14109 Ruhr-Universitaet | Fon/Fax (private): +49 234 33 22 75 D-44780 Bochum, Germany | eMail: Christoph.van.Wuellen@Ruhr-Uni-Bochum.de ---------------------------+------------------------------------------------ From chemistry-request@server.ccl.net Tue Mar 7 15:35:26 2000 Received: from if1.if.ufrgs.br (if1.if.ufrgs.br [143.54.4.2]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id PAA04803 for ; Tue, 7 Mar 2000 15:35:24 -0500 From: PEROTT@if.ufrgs.br Received: from if1.if.ufrgs.br by if1.if.ufrgs.br (PMDF V4.3-10 #7035) id <01JMRABWQ9IO0012M7@if1.if.ufrgs.br>; Tue, 07 Mar 2000 16:28:32 -0003 Date: Tue, 07 Mar 2000 16:28:32 -0003 Subject: Mass storage devices To: chemistry@server.ccl.net Message-id: <01JMRABWR2GI0012M7@if1.if.ufrgs.br> X-VMS-To: IN%"chemistry@www.ccl.net" MIME-version: 1.0 Content-type: TEXT/PLAIN; CHARSET=US-ASCII Content-transfer-encoding: 7BIT Hi ! A feature common to most of the computational chemistry software currently available is the huge amount of data that is frequently read/write from/to scratch files. The performance of a computational chemistry application so depends largely on transference rates from/to hard discs or other mass storage devices. In this context, let me address a couple of questions to the list: i) what is the best strategy (in terms of best performance): write a few, huge files to huge disk partitions or, alternatively, split big files into smaller ones over many disk partitions? ii) could someone point to additional information on fast access mass storage devices? I'll summarize to the list! Claudio.