Gaussian 03 Online Manual
Last update: 4 April 2003

mm

Standalone molecular mechanics program. This program reads a Gaussian input file from standard input and writes a new input file with the (possibly optimized) structure to standard output. The desired force field must be selected via the -Dreiding, -UFF, -Amber or -Param option (see below for the latter). The type of job to run is specified with the -Force, -Freq, -Opt, and -Micro command line options; the default is an energy calculation. -Micro optimizes only the atoms that are in the real system (in order to preoptimize the MM portion of the molecule).

ADDITIONAL COMMAND LINE OPTIONS

-Param N
Use force field N (same as IOp(1/64)=N within Gaussian).

-ReadParam
Read in additional parameters. Internally-stored parameters have priority over read-in parameters.

-ReplaceParam
Read in additional parameters. Read-in parameters take priority over the internally-stored parameters

-OptCyc N
Specify the maximum number of optimization cycles to N.

-ReadCon
Read connectivity information from the input file (i.e., the input file uses Geom=Connect).

-Test N
Set the debugging flag to N (higher numbers result in more debugging output).

-TRScale num
Use scaling scheme num for rigid translations/rotation: 0=no scaling (the default); 1 says to scale the N atoms in a rigid block by 1/N; 2 says to scale the N atoms in a rigid block by 1/SQRT(N), and a negative value scales by |N|/1000.