KERNEL TRUNCATION/LCOARSEN

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KERNEL_TRUNCATION/LCOARSEN = .True. | .False.
Default: KERNEL_TRUNCATION/LCOARSEN = .True. 

Description: KERNEL_TRUNCATION/LCOARSEN speeds up computation of the local potential in the kernel truncation method by coarsening the charge density before padding it


Kernel truncation methods pad the computational cell with vacuum. This padded cell is expensive to compute due to FFTs being performed on a larger grid. The KERNEL_TRUNCATION/LCOARSEN method selectively replaces the long range potential with the truncated potential instead of computing the entire potential on a padded grid. This selective replacement of the potential bypasses the need for padding, speeding up the computation of the kernel truncation methods.

Mind: IF KERNEL_TRUNCATION/LTRUNCATE is switched off, all other KERNEL_TRUNCATION tags, i.e. KERNEL_TRUNCATION/IDIMENSIONALITY, KERNEL_TRUNCATION/LCOARSEN, and KERNEL_TRUNCATION/ISURFACE will be ignored.

Related tags and articles

KERNEL_TRUNCATION/LTRUNCATE, KERNEL_TRUNCATION/IDIMENSIONALITY, KERNEL_TRUNCATION/ISURFACE