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hi, i am in a trouble well i was using a odd Kpoint for calculation in a small cell containig 3 atoms it´s a Kpnt file like this
K-Points
0
Monkhorst Pack
11 11 11
0 0 0

but now i need to use a supercell based in the replication of 3x3x2 times the basic unit cell (containig 3 atoms) i was reading the manual and some handsons files from the site and they told me that if i would have used even Monkhorst pack Kpoint i would only need to decrease the Kpoint number for the same proportion as the basic unit cell is increase in this case x =3 and x= 2 in the x and y direction respectively

but in the case i use odd Kpoint which Kpoint can i use for me supercell? can i use odd Kpoint for me supercell ? jow many Kpoint should i use?

i would be so kindnees to answer my question it is important for me.

yes of course. I would use a 3x3x5 mesh (if you want to keep tho the odd mesh).

thanks for your help i understand the way to choose the kpoint but i have another problem i did what you explain me to use i i had a message like this in the prompt What is that?



VERY BAD NEWS! internal error in subroutine IBZKPT:
Reciprocal lattice and k-lattice belong to different class of lattices. 48
POSCAR, INCAR and KPOINTS ok, starting setup


can you help me to solve the problem please?

thank you in advance

the symmetrization routines sometimes fail for systems with low symmetry (unfortunately including hexagonal) if you use an even k-mesh (please have a look at the k-points.pdf file of the VASP-workshop tutorial). Please
--) use an odd k-mesh. If this does not solve the problem
--) turn off all symmetrisation (ISYM=0)