MacroModel Reference Manual - ISP

Chapter 4: Operation Codes1 Stretch2 Bend3 Torsion (proper and improper)4 Nonbonded8 Solvation 19 Solvation 210 Solvation 311 Stretch-bend12 Bend-bend13 Stretch-torsion14 Charge-multipole electrostatics15 Wilson-angle out-of-plane termsarg4arg5Number of calls to derivative routine before derivative checkingUsed for testing of constant derivative options (Default: 1).Step length (Angstroms) for numerical derivative calculationDefault depends on the potential function selected, but is 0.0001 except for Solvation1 and Bend-bend.ASET — Atom SETsThis command is used to place atoms into mutually exclusive sets. During a subsequent ELSTprocedure (with any ELST arg1 value other than 4) the energy components are printed separatelyfor the interactions within each set, as well as between pairs of sets. Although the setsmust be mutually exclusive, they need not, collectively, include all the atoms in the molecule.If DEBG flag 1 is turned on, the set membership is listed in the log file at the time of the ELSTcommand.The various ASET energies are a pairwise breakdown of the interaction energies obtained byadding up the individual atom-atom interaction energies. This approach has difficulties withGB/SA solvation because it is not a pairwise additive potential. In the generalized Born (GB)approach the solvation energy depends on the Born radii each of which depend in a complex48MacroModel 9.7 Reference Manual