compute_shc
¶
The compute_shc
keyword is used to compute the non-equilibrium virial-velocity correlation function
Syntax¶
compute_shc <sample_interval> <Nc> <transport_direction> <num_omega> <max_omega> [{<optional_arg>}]
sample_interval
is the sampling interval (number of steps) between two correlation steps.
This parameter must be an integer that is
Nc
is the total number of correlation steps.
This parameter must be an integer that is
transport_direction
is the direction of heat transport to be measured.
It can only be 0, 1, and 2, corresponding to the
num_omega
is the number of frequency points one wants to consider.
max_omega
is the maximum angular frequency (in units of THz) one wants to consider.
The angular frequency data will be max_omega/num_omega, 2*max_omega/num_omega, ..., max_omega
.
<optional_arg>
can only be group
, which requires two parameters:
group <grouping_method> <group_id>
This means that group_id
of grouping method grouping_method
.
Usually, group_id
should be grouping_method
.
If grouping_method
is assigned and group_id
is -1, it means to calculate the group_id
except for group_id
0 in the assigned grouping_method
.
Since it is very time and memory consuming to calculate the all group group_id
0.
Also, grouping method grouping_method
must be defined in the simulation model input file.
If this option is missing, it means computing
Examples¶
Example 1¶
The command:
compute_shc 2 250 0 1000 400.0
means that
you want to calculate
for the whole systemthe sampling interval is 2
the maximum number of correlation steps is 250
the transport direction is
you want to consider 1000 frequency points
the maximum angular frequency is 400 THz
Example 2¶
The command:
compute_shc 1 500 1 500 200.0 group 0 4
means that
you want to calculate
for atoms in group4
defined in grouping method0
the sampling interval is 1 (sample the data at each time step)
the maximum number of correlation steps is 500
the transport direction is
you want to consider 500 frequency points
the maximum angular frequency is 200 THz
Example 3¶
The command:
compute_shc 1 500 1 500 200.0 group 1 -1
means that
you want to calculate
for allgroup_id
except forgroup_id
0 defined in grouping method1
the sampling interval is 1 (sample the data at each time step)
the maximum number of correlation steps is 500
the transport direction is
you want to consider 500 frequency points
the maximum angular frequency is 200 THz
Caveats¶
This computation can be memory consuming.
If you want to use the in-out decomposition for 2D materials, you need to make the basal plane in the