dahist calculates a distance-angle map for an A...B-C interaction, giving both the A-B-C angle map and the A-B distance histrogram as output.

Related programs:

  • To calculate individual atomic partials for one species, see rdfaa.

Basic Usage

dahist <HISTORYfile> <OUTPUTfile> <sp1> <sp2> <maxdist> [-triplet a b c] [-frames n] [-mindist d]


  • <HISTORYfile> is the name of the DL_POLY HISTORY file
  • <OUTPUTfile> is the name of the DL_POLY OUTPUT file
  • <sp1> is the integer index of the species possessing atom 'a' in the interaction
  • <sp2> is the integer index of the species possessing atoms 'b' and 'c' in the interaction
  • <maxdist> is the maximum allowable distance for a-b for it to be considered

Although this is enough to run dahist, at least one triplet of atoms muse be specified with the -triplet switch.


-frames n

Stop calculating after processing n frames.

-mindist d

Specifies a minimum allowable distance for the atoms a-b, below which they will not be considered (default = 0.0).

-triplet a b c

Add a triplet a-b-c to the calculation. Note that if multiple triplets are defined these contribute to the same distance-angle map - if separate maps are required for each triplet the code must be called individually for each.


Given an input HISTORY file results.HISu, then output files are as follows: results.dahistNNAAMMBBCC.hist : histogram of the a-b distances found in the calculation results.dahistNNAAMMBBCC.surf : distance angle map of the a-b-c interaction in three column format (distance, angle, histogram value) with a blank line separating each angle