Unless documented otherwise, the following units are used
- angstrom for all distances
 
- \( \frac{kcal}{mol \unicode[serif]{xC5}}\) for forces/derivatives
 
- \(\frac{kcal}{mol}\) for energies
 
- radians for angles. All angles are counterclockwise.
 
- all charges are in units of the elementary charge
 
- all times are in femtoseconds