I am still a fairly new graduate student, and I am having trouble simulating a metal-organic framework. I am currently using UFF (I implemented it for LAMMPS), and it works well for some MOFs, but does not give empirically accurate results for others. What I mean by this is that I have a CIF file for the experimentally obtained structure, and when simulate it, the structure changes.
UFF is fairly old (1992?); there's got to be something better that will allow this to match the experimental structure. Any ideas? Currently, I'm obtaining partial charges for the solvent molecules, copper ions, and chlorine from various papers, but I am considering trying to use Gaussian even though I have never done that before. UFF is generally used without partial charges, but I think the strong electrostatics in my MOF necessitates their use.
The MOF contains carbon, nitrogen, hydrogen, chlorine, oxygen, and copper.
(I'm still working with the possibility that I may have screwed something up somewhere in the simulation process, but I would still think there's something newer/more accurate than UFF).