A question on Alchemy calculation

98 views

Skip to first unread message

Binquan Luan

unread,

Nov 5, 2021, 2:13:51 PM11/5/21

to cp2k

Dear all,

I am learning the alchemy method in cp2K. I played with the example in ../tests/FE/regtest-1. The k value (see blow) is set to 0.5. The program outputs the value of $\Delta_G$ between two subsystems (X and Y). But if I change k to other values, the output results are different. Should I change k from 0 to 1 and do the integration? It is not clear to me. Thanks for help.

&MULTIPLE_FORCE_EVALS
   FORCE_EVAL_ORDER 2 3
   MULTIPLE_SUBSYS T
&END
&FORCE_EVAL
METHOD MIXED
&MIXED
    MIXING_TYPE GENMIX
    &GENERIC
      # X: Energy force_eval 2
      # Y: Energy force_eval 3
      MIXING_FUNCTION k*X+(1.0-k)*Y
      VARIABLES X Y
      PARAMETERS k
      VALUES 0.5
    &END