[Pw_forum] Band Structure and nscf calculation

[Sohail Ahmad]

Dear
I ran scf for MoS2 in K_Points Automatic 4X4x4 mesh with 20 nband and followed calculation for band Structure
but i observed that sufficient no. of bands are not there;; 
then i perform nscf calculation for DOS which seems to be alright

So i did scf calculation again in K-Points Automatic 12x12x12 with a little increase in nband (keeping it in mind nband = # of VE/2 +20% more in metal)

Now i have few questions

1-- While performing band calculation, how should i take K-points
     K-POINTS AUTOMATIC
     12x12x12 1 1 1
    or the one which i generated manually (150 Points)
     150
     ---- ---- ---- 1
     ---- ---- ---- 2
     like that,,,,,,,,,,,,,,,,,,,,,,,,,,,,,which one is a better option  ????

2. While performing nscf calculation, should i write it or no
    restart_mode = 'from_scratch',
    i believe no as it may take longer time and some convergence conflict
    but i need confirmation
   
    Its mentioned in the user guide, that occupations = tetrahedra for DOS
    Is it required in every case irrespective of magnetic or non magnetic  ???

3  i think nscf is required only for DOS, So can i perform nscf calculation befor the post          processing calculation of band calculation  ?????
    This question i am asking because i am using computational facility of some other    place which is available to me for short time only and i am running short of time

Sohail
KKU
SAUDI 
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