Why does the tetrahedron method have to be used with a gamma-centered k-mesh?

[nigel_hew]

This is a pretty general question. Why does ISMEAR=-5 have to be used with a gamma-centered k-mesh according to https://www.vasp.at/wiki/index.php/ISMEAR? I tested a static calculation with ISMEAR=-5 with the gamma and Monkhorst pack and they gave me the same converged energies.

Regards,
Nigel Hew
Penn State Postdoc

[alexey.tal]

Hi,

The tetrahedron method in VASP does work with both the Gamma-centered and Monkhorst-Pack k-meshes. In some cases VASP might be unable to construct a generating k-lattice. To avoid this problem make sure to include the Gamma point in the k-mesh. But if such case is encountered an error should be shown together with suggestions on how to avoid this problem.

[nigel_hew]

Thanks!