The compute sdc keyword

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Purpose

  • This keyword computes the self diffusion coefficient (SDC) using the velocity autocorrelation (VAC). If this keyword appears in a run, the VAC will be computed and integrated to compute the SDC.

Grammar

  • For this keyword, the command looks like:
 compute_sdc sample_interval Nc <optional_arg>

with parameters defined as:

  • sample_interval: Sampling interval of the velocity data
  • Nc: Maximum number of correlation steps

The optional_arg allows an additional special keyword. The keyword for this function is group. The parameters are:

  • group group_method group
group_method: The grouping method to use for computation
group: The group in the grouping method to use

Examples

Example 1

  • An example of this function is:
compute_sdc 5 200 group 1 1

This means that you (1) want to calculate the SDC; (2) the velocity data will be recorded every 5 steps; (3) the maximum number of correlation steps is 200; (4) You would like to compute only over group 1 in group method 1.

Caveats

  • This function cannot be used in the same run with the compute_dos keyword.

Output file