formpair.xmo

来自「一个很好的分子动力学程序」· XMO 代码 · 共 82 行

XMD (Version 2.5.29 Nov 27 2000)

Not using pthread library.
Not using asm("finit"); patch in thread routines.
#######################################################################
#                                                                     #
#  Example:  Using FORMULA option with PAIR potential model           #
#                                                                     #
#######################################################################
#    The FORMULA option allows you to build up a potential table      #
#  by specifying the actual formula for your function, rather         #
#  than entering a table of values.                                   #
#     This example also demonstrates the use of the POTENTIAL EVAL    #
#  command available with the PAIR potential model.                   #
#                                                                     #
#######################################################################
#     The format of the potential command is                          #
#                                                                     #
#               POTENTIAL PAIR type1 type2 ntable r0 rn  FORMULA      #
#                                                                     #
#  where   type1  is the first  atom type of the pair potential       #
#          type2  is the second atom type of the pair potential       #
#          ntable is the number of entries in the potential table     #
#          r0     is the radius corresponding to the table beginning  #
#          rn     is the radius corresponding to the table end        #
#                                                                     #
#######################################################################
#
#
#  Choose pair potential model
#
POTENTIAL SET PAIR 2
#
#  Set parameters for "quartic" potential function
#
CALC Ro    = 1.67
CALC RC    = 3.40
CALC DEPTH = 1
#
#  Produce potential using formula for quartic potential
#
EUNIT erg
POTENTIAL PAIR  1 2   100  0  3.40  FORMULA 
#
#  Evaluate resulting potential
#
CALC r = 0
repeat 21
   POTENTIAL EVAL PAIR 1 2  0 r
   CALC r = r + 0.170
end
        7.19376
        5.17962
        3.53096
        2.20638
        1.16674
        0.375089
        -0.203243
        -0.600708
        -0.847517
        -0.971642
        -0.998818
        -0.952542
        -0.854073
        -0.722432
        -0.574404
        -0.424533
        -0.285128
        -0.166259
        -0.0757575
        -0.0192191
        -6.05607e-18

TIME INFORMATION
   Ending   Time: 03/19/2001   13:37:10
   Elapsed  Time: 0 min 00 sec

ERROR STATISTICS
   Number of Fatal Errors:               0
   Number of Unknown Command Errors:     0
   Number of Misc. Warnings:             0