The question about the KPOINTS.
Posted: Sat May 15, 2010 7:49 pm
I'm puzzled by the kpoints-generation in the manual.
The manual shows us two ways of producing KPOINTS.
The first is like this :
Auto
0
4 4 4
0 0 0
The second is like this :
Auto generation
0
Cartesian
0.25 0.00 0.00
0.00 0.25 0.00
0.00 0.00 0.25
0.50 0.50 0.50
And for the fcc ,they are equate with each other .
I have several questions as follows:
1.How one translate into another one ?
2.For low-symmetry system, can the translation still work ?
3.I'm recently do some test about the HSE06/B3LPY/PBE0 ,and the file with log always gives a warring like this :
-----------------------------------------------------------------------------
| |
| W W AA RRRRR N N II N N GGGG !!! |
| W W A A R R NN N II NN N G G !!! |
| W W A A R R N N N II N N N G !!! |
| W WW W AAAAAA RRRRR N N N II N N N G GGG ! |
| WW WW A A R R N NN II N NN G G |
| W W A A R R N N II N N GGGG !!! |
| |
| Your generating k-point grid is not commensurate to the symmetry |
| of the lattice. This can cause slow convergence with respect |
| to k-points for HF type calculations |
| suggested SOLUTIONS: |
| ) if not already the case, use automatic k-point generation |
| ) shift your grid to Gamma (G) (e.g. required for hex or fcc lattice) |
| |
-----------------------------------------------------------------------------
Does the second ways of generate KPOINTS really improve the performance of the computation ?
Waiting your reply .
<span class='smallblacktext'>[ Edited ]</span>
The manual shows us two ways of producing KPOINTS.
The first is like this :
Auto
0
4 4 4
0 0 0
The second is like this :
Auto generation
0
Cartesian
0.25 0.00 0.00
0.00 0.25 0.00
0.00 0.00 0.25
0.50 0.50 0.50
And for the fcc ,they are equate with each other .
I have several questions as follows:
1.How one translate into another one ?
2.For low-symmetry system, can the translation still work ?
3.I'm recently do some test about the HSE06/B3LPY/PBE0 ,and the file with log always gives a warring like this :
-----------------------------------------------------------------------------
| |
| W W AA RRRRR N N II N N GGGG !!! |
| W W A A R R NN N II NN N G G !!! |
| W W A A R R N N N II N N N G !!! |
| W WW W AAAAAA RRRRR N N N II N N N G GGG ! |
| WW WW A A R R N NN II N NN G G |
| W W A A R R N N II N N GGGG !!! |
| |
| Your generating k-point grid is not commensurate to the symmetry |
| of the lattice. This can cause slow convergence with respect |
| to k-points for HF type calculations |
| suggested SOLUTIONS: |
| ) if not already the case, use automatic k-point generation |
| ) shift your grid to Gamma (G) (e.g. required for hex or fcc lattice) |
| |
-----------------------------------------------------------------------------
Does the second ways of generate KPOINTS really improve the performance of the computation ?
Waiting your reply .
<span class='smallblacktext'>[ Edited ]</span>