MacroModel Reference Manual - ISP

Chapter 4: Operation CodesASL1 — ASL expression for substructureSpecify ASL syntax for a substructure. This command is intended to make it easier to set upstandardized substructures that can be reused in different calculations on different molecularsystems.Note:This special command can only be used in substructure (.sbc) files: it cannot be usedin command (.com) files.The format of this command is similar to that of regular opcodes, starting with a 4-characterstring. The first argument is a floating-point number that has the same meaning as arg5 ofSUBS, and the second argument is a string.arg1Add/Delete atoms0 Add the atoms defined by the ASL expression to the substructure. (Default)−1arg2Remove the atoms defined by the ASL expression from the substructure.ASL expressionSee the Maestro Command Reference Manual for information on ASL syntax.ASL2 — ASL expression for fixed and frozen atomsSpecify ASL syntax for fixed and frozen atoms, similar to the FXAT opcode. This command isintended to make it easier to set up standardized substructures that can be reused in differentcalculations on different molecular systems.Note:This special command can only be used in substructure (.sbc) files: it cannot be usedin command (.com) files.The format of this command is similar to that of regular opcodes, starting with a 4-characterstring. The first argument is a floating-point number, and the second argument is a string.arg1Fix or freeze atoms>0 Specify the force constant for the atoms defined by the ASL expression, which are“fixed” atoms−1arg2Freeze the atoms defined by the ASL expression.ASL expressionSee the Maestro Command Reference Manual for information on ASL syntax.66MacroModel 9.7 Reference Manual