MacroModel Reference Manual - ISP

Chapter 4: Operation Codesarg3Molecular or stochastic dynamics selection0 Molecular dynamics (default).1 Stochastic dynamics. Temperature control is an integral part of stochastic dynamicsand a nonzero temperature must supplied in arg7. With stochastic dynamics, atimestep of no more than 1.5 fs and SHAKE is recommended. Generates the canonical(constant-temperature) ensemble.Total translational and rotational momentum is reset (zeroed out) by default whenordinary molecular dynamics is run, but not when stochastic dynamics is run. Thisbehavior can be overridden using the MDMT command.arg4Frequency of data collectionUsed to determine the time interval for computation of average enthalpy.0 Default: 25 fs, but 5 fs for runs of less than 10 ps; increased for runs of more than1000 ps.narg5arg6n fsDynamics time step in femtoseconds (default 1.5 fs)Total time of dynamics run0 Default: 1.0 ps.>0 Interpreted as ps.