[gmx-users] RE: heat capacity etc.

[David van der Spoel]

On 2011-03-11 19.53, Thomas Koller wrote:
> I have version 4.0.5 and there is no enthalpy in the g_energy tool. Do you see a chance to calculate the isobaric heat capacity as well as the thermal compressibility, which is also not shown?
>
> Thomas
Then you have to compute the enthalpy yourself by summing Etot and 
pressure times volume (use the applied pressure, not the measured 
pressure). Based on this you can look up the equations to compute the 
heat capacity. Check the manual for quantum corrections to harmonic 
potentials, however this is not trivial, in fact it is an open question 
that we are trying to address in a paper under review.

The alternative may be to redo the sim in gmx 4.5.3, where the enthalpy 
is stored in the edr file and some of the analysis is automated better.

-- 
David van der Spoel, Ph.D., Professor of Biology
Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205.
spoel at xray.bmc.uu.se    http://folding.bmc.uu.se