Previous Thread
Next Thread
Print Thread
What is the unit for velocity in output file?
#1465 05/21/04 05:47 PM
Joined: May 2004
Posts: 46
Z
zhangy Offline OP
Forum Member
OP Offline
Forum Member
Z
Joined: May 2004
Posts: 46
When running a dynamic simulation, the velocities of atoms are saved in the unit defined by IUNVEL. So what is the unit used in this file?
Thanks

Re: What is the unit for velocity in output file?
zhangy #1466 05/21/04 07:11 PM
Joined: Sep 2003
Posts: 8,479
rmv Online Content
Forum Member
Online Content
Forum Member
Joined: Sep 2003
Posts: 8,479
If you are asking about what unit number to use with IUNVEL, that's done in a fashion analogous to IUNCRD for a coordinate trajectory, e.g.

open unit 41 write file name dyn.trj
open unit 42 write file name dyn.vel
dyna leap strt timestep 0.001 nstep 100000 -
iuncrd 41 inuvel 42 -
... etc.

If you're asking about the units for the velocities, they are Angstrom/AKMA-time, where AKMA-time is the internal time unit used in CHARMM, and 20 AKMA time units is .978 picoseconds (1 AKMA time unit = 4.888821E-14 sec).




Rick Venable
computational chemist


Moderated by  lennart, rmv 

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.4
(Release build 20200307)
Responsive Width:

PHP: 5.6.33-0+deb8u1 Page Time: 0.011s Queries: 18 (0.005s) Memory: 0.8923 MB (Peak: 0.9579 MB) Data Comp: Off Server Time: 2020-08-09 00:09:06 UTC
Valid HTML 5 and Valid CSS