Subject: Molecular Dynamic Simulation of Liquid Crystals

From: Jane-Jane Ou <[email-masked]>
Date: Thu, 13 Apr 95 10:09:59 EDT

Hi,

I am simulating liquid crystal materials.   I wrote the program 
myself with 64 molecules in a box with periodic boundary conditions.  
I use Alchemy's force field constants to simulate ocb5.  The density
I got from the simulation is too low, and the order parameters too
high.  There is not much difference with MM2's exp-6-1 van der 
Waals and torsion potentials.  I also tried Picken et. al. (Liq.
Cryst., 1989)'s united atom parameters to simulate cb5.  The
results I got are:
	Temperature	Order	Density	   
	   290K		0.48	0.990	  
	   300K		0.43    0.970
	   310K		0.39    0.965
	   320K		0.36	0.962
Densities are also too low.  Is there MD program available somewhere?
And what force field programs are available?  Please send your opinion,
suggestion or advice to my address at [email-masked].    
Thank you very much.

Sincerely,

Jane J. Ou
[email-masked]