I have few questions regarding convergence/accuracy confirmation for EPW results.
1)Regarding degaussw (as given in Pb example) : How can we fix this parameter based on calculations !! For e.g my lambda and Tc values are given below which are completely effective with smear parameter (In all cases I used nk1,nk2,nq1,nq2 as 8 and nkf1,nkf2,nqf1,nqf2 as 32)
Smear lambda Tc
0.1 2.84 16 K
0.2 2.24 13 K
0.25 2.01 11 K
0.35 1.79 9.7 K
0.5 1.69 8.5 K
i.e. 0.5 eV smearing is physically meaning !! which is also giving above 1.5 lambda value. From my knowledge smearing parameter is representing the electronic temperature, where FD smear is better than gauss or mp methods. So, How can I set my smearing method in epw.in method??
Is it necessary of above check for degaussq in MgB2 example ???
2)Regarding eptemp: From the general discussions in the forum, I found
eptemp is the temperature at which you want your results. The temperature eptemp will give the value of the Bose-Einstein n(T) factors
Which means, Is it represent Real temperature !!!
3)Phonon q-mesh for EPW input: Indeed I found positive phonon modes with 32X32X1 K-mesh and 8X8X1 q-mesh (10 qpoints) for 2D material. Still EPW input need more q-mesh i.e. 12X12 (19 qpoints) or 16X16 (30 qpoints) sets ???
Thanks in advance
With regards
Samudrala