The compute hac keyword

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Purpose

The compute_hac keyword is used to calculate the HAC (heat current autocorrelation) and RTC (running thermal conductivity) using the Green-Kubo method.

Grammar

  • This keyword has 3 parameters and will have the following format:
compute_hac sampling_interval correlation_steps output_interval

The first parameters is the sampling interval for the heat current data. The second parameter is the maximum correlations steps. The third parameter for compute_hac is the output interval of the HAC and RTC data.

Examples

Example 1

  • An example of the keyword is:
compute_hac 20 50000 10

This means that you (1) want to calculate the thermal conductivity using the Green-Kubo method; (2) the heat current data will be recorded every 20 steps; (3) the maximum number of correlation steps is 50000; (4) the HAC/RTC data will be averaged for every 10 data and the number of HAC/RTC data output in a given direction is then 50000/10 = 5000. The results will be written into a file name hac.out in the same folder where you put your run.in

Caveats

Related keywords

compute_hnemd