From chemistry-request ^%at%^ server.ccl.net Fri Jul 19 21:12:23 2002 Received: from travelers.mail.cornell.edu ([132.236.56.13]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g6K1CMB07179 for ; Fri, 19 Jul 2002 21:12:22 -0400 Received: from travelers.mail.cornell.edu (travelers.mail.cornell.edu [132.236.56.13]) by travelers.mail.cornell.edu (8.9.3/8.9.3) with SMTP id VAA00091; Fri, 19 Jul 2002 21:12:21 -0400 (EDT) Date: Fri, 19 Jul 2002 21:12:21 -0400 (EDT) From: rlw28 #at# cornell.edu X-Sender: rlw28-: at :-travelers.mail.cornell.edu To: chemistry |-at-| ccl.net cc: rlw28 -A_T- cornell.edu, rwood005 -A_T- twcny.rr.com Subject: I have yet ANOTHER stupid CHARMM question... Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Hi all I have yet ANOTHER stupid CHARMM question. I'm doing a verlet simulation on a system other than a water box, namely my solvated peptide which I just fixed (finally). I'm currently in the process of heating my system from 100 to 300 K in 50 K steps. My question is this: what values should I use for IHTFRQ, the heating frequency, and TEMINC, the heating increment in degrees K? My 50 K heatings run last for 10,000 time teps; I've broken it up into 4 10 ps heatings. I was thinking something along these lines, namely that the number of steps divided by IHTFRQ times TEMINC should be equal to the change in temperature, or in this case 50. In the CHARMm dictionary, published by MSI, there is an example where the number of steps, STEPS is 3000, IHTFRQ is 50, and TEMINC is 5. Does this always hold, or am I goofy? In my run, I've set IHTFRQ to be 100 and this means that TEMINC would be 0.5. My NSTEPS are 10000. Are these values of IHTFRQ and TEMINC ok? Thanks in advance for your assistance. Cheers, Richard