I have a question about Material Studio. Actually I'm a beginner to deal with this software. I would like to use forcite calculation to do my simulation. I have a problem with this calculation. I would like to use COMPASS as a force field but one of my compound (Boron) can't find in this force field. Then, I tried to change the force field using Universal Force Field and it's work. My question are:

1. What is the different between using COMPASS and Universal Force Field for calculation?

2. If I want to use COMPASS Force Field, it means I have to add the compound (Boron) at the database. How to add the database of this compound? Is there any equation that we have to add?

Thank you.