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SPARC-X / SPARC

Simulation Package for Ab-initio Real-space Calculations
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What is the preferred K-point grid? #177

Closed Jiang-eat-sugar closed 1 year ago

Jiang-eat-sugar commented 1 year ago

Hi,

I tried to use a similar rule of thumb for the K-point grid in vasp calculation (ak=30). It greatly increased the cost of the computation resources. Then, I saw K-point grid is 2 2 2 in the testing example "AlSi_primitive_quick_relax" with a cell size of 7 7 * 7. Does anyone know if there is a rule of thumb for the K-point grid in sparc-X calculation?

Thanks, Jiang

phanish-suryanarayana commented 1 year ago

The k-point grid in all DFT codes works in the same way. In other words, the number of k-points required should not change between DFT codes for the same choice of smearing. Note that SPARC does not do symmetry reduction in k-points, so the increase in cost might appear substantial.