Name

acceptor — Decides whether or not to accept a proposed particle configuration change.

Description

The acceptor element holds information about how to generate the acceptance probability, as well as some information about the reaction path.

Processing expectations

None

Parents

mcupdate

Children

none

Attributes

type

Required, the procedure by which to decide whether or not to accept moves. Default is ``canonical'', selecting the canonical ensemble. Other options are ``microcanonical'', and ``always'' (accept every attempted move).

Implementation details

The acceptor element hold the information for the procedure which accepts or rejects Monte Carlo particle configuration changes. It must be included within mcupdate.

The list of meaningful acceptor parameters.

nameconditiondatatypedefaultmeaning
reaction_pathn/astring "default" The file from which to read in the reaction path.
numframesn/aint1The number of particle configurations specified in reaction_path.
segment_lengthAngstroms scalar 0.0 The distance between frames in the reaction_path read in. Only necessary if one is not using interpolate_frames parameter, otherwise it is recalculated after interpolation.
interpolate_framesn/aintn/aThe number of frames to use for the reaction coordinate, which is interpolated from reaction_path.
temperatureeV scalar 0.0 The temperature to use for the canonical ensemble. Only valid if the canonical ensemble is used.
total_energyeV scalar 0.0 The total energy to use for the microcanonical ensemble. Only valid if the microcanonical ensemble is used.
reg_startn/aint0Do not let the system explore particle configurations that project to reaction coordinate values less than this. If used, should also set region_finish. Also, beware that in the current implementation, these numbers are read in again in the mcupdate element and the two locations' values must agree.
reg_finishn/aint1Do not let the system explore particle configurations that project to reaction coordinate values greater than this. If used, should also set region_start. Also, beware that in the current implementation, these numbers are read in again in the mcupdate element and the two locations' values must agree.

Examples

This example shows to how to set up the acceptor simulation with some typical options.

  <acceptor type="canonical">
    <parameter name="reaction_path">longer_straight_path.xyz</parameter>
    <parameter name="numframes">1000</parameter>
    <!-- Specify "segment_length" if not interpolating more frames or "interpolate_frames" if you are-->
    <parameter name="segment_length">4.37820e-03</parameter>
    <!--parameter name="interpolate_frames">1000</parameter-->
    <!-- for now, temperature is specified in units of k_B*T; that is, eV-->
    <parameter name="temperature">0.10</parameter>
    <parameter name="reg_start">370</parameter>
    <parameter name="reg_finish">505</parameter>
  </acceptor>