From chemistry-request -8 at 8- server.ccl.net Tue Jun  4 22:39:21 2002
Received: from rwcrmhc52.attbi.com ([216.148.227.88])
	by server.ccl.net (8.11.6/8.11.0) with ESMTP id g552dKF30837
	for <chemistry -A_T- ccl.net>; Tue, 4 Jun 2002 22:39:21 -0400
Received: from daveg-lifebook.cachesoftware.com ([12.224.212.36])
          by rwcrmhc52.attbi.com
          (InterMail vM.4.01.03.27 201-229-121-127-20010626) with ESMTP
          id <20020605023915.MDLG2751.rwcrmhc52.attbi.com "-at-" daveg-lifebook.cachesoftware.com>;
          Wed, 5 Jun 2002 02:39:15 +0000
Message-Id: <5.1.0.14.0.20020604190716.039d3340 ^%at%^ pop3.norton.antivirus>
X-Sender:  (Unverified)
X-Mailer: QUALCOMM Windows Eudora Version 5.1
Date: Tue, 04 Jun 2002 19:17:43 -0700
To: Jianquan Chen <jianquan _-at-_)eden.rutgers.edu>
From: David Gallagher <dgallagher \\at// cachesoftware.com>
Subject: Re: calculate charge using MOPAC
Cc: chemistry "-at-" ccl.net
In-Reply-To: <Pine.GSO.4.21.0206041212060.19877-100000.,at,.er6.rutgers.edu>
References: <6D47A7D05774D411959200508BDF739A024382FA ^%at%^ nlgln50ntms001.gln51.dsm-group.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"; format=flowed

Hi Jianquan

1.      MOPAC can run just an "SCF" which does not change the geometry. 
This is the fastest way to get partial charges.

2.      The new linear-scaling versions of MOPAC can calculate up to 20,000 
atoms in just a few hours on a Windows desktop computer. With "MOPAC 2002", 
an SCF on a 641 atom protein takes about 3 minutes on a 1000 MHz Pentium 
III. There is more information at 
http://www.cachesoftware.com/mopac/index.shtml

David Gallagher, Fujitsu

At 12:22 PM 6/4/2002 -0400, Jianquan Chen wrote:
>Hi,
>I need to add charge to thousands of molecules. MOPAC is free but slow and
>sometimes  changes the moleucular structure. I don't know how MOPAC
>works. I have 2 questions.
>Can I run MOPAC without optimizing the molecular
>structure?
>Is there any way to accelate MOPAC? I don't need very accurate charges.
>
>Thanks a lot for any response.
>
>
>Jianquan Chen
>
>
>
>-= This is automatically added to each message by mailing script =-
>CHEMISTRY ^at^ ccl.net -- To Everybody  | CHEMISTRY-REQUEST ^at^ ccl.net -- To Admins
>MAILSERV#* at *#ccl.net -- HELP CHEMISTRY or HELP SEARCH
>CHEMISTRY-SEARCH ":at:" ccl.net -- archive search    |    Gopher: gopher.ccl.net 70
>Ftp: ftp.ccl.net |  WWW: http://www.ccl.net/chemistry/  | Jan: jkl%!at!%ccl.net