OPLS-aa parameters for alkylsilanes

NOTE: This forcefield is currently under construction!

Source Notes:

Additional Notes:

  • To be consistent with conversions performed by OpenMM (http://openmm.org)
    • The original parameters are defined as kcal/mol, this file uses kJ/mol; a conversion factor of 4.184 was used.
    • PI is defined as 3.141592653589 for conversion to radians.
  • Conversion from OPLS-style dihedrals to RB follow the formulas detailed in the GROMACS manual (http://gromacs.org).
    • Specifically, the OPLS form is given as:
0.5*(F1*(1+cos(phi))+ F2*(1-cos(2phi))+ F3*(1+cos(3phi))+F4*(1-cos(4phi)))
  • The RB mapping:
c0 = F2+0.5*(F1+F3)
c1 = 0.5*(-F1+3F3)
c2 = -F2 + 4F4
c3 = -2F3
c4 = -4F4
c5 = 0
  • Example molecules with correct atomtypes are defined as test cases. Execute the testing script using py.test -v --tb=line

Force field DOI