ABINIT Discussion Forums

Dear Abinit crew,

I have been performing Optic calculations on hot molecular systems, and I have found that the thermalized electronic occupancies are not carried through to the spectrum calculation. This may be closely related to Guangfu Luo's post: viewtopic.php?f=10&t=1262.

I found that the optic.F90 code reads the occupancies from the header of a "1WF" file (a ddk perturbation). I found from the ddk perturbation code that these are dummy integer occupancies, and the fermi energy is a dummy zero. I fixed the problem by reading the occupancies and fermi energy instead from the "WFK" file in the optic input (line 4). In this case, we get the thermalized occupancies and the correct fermi energy. This has a large effect on my calculated spectra- an order of magnitude or two at very low frequency (depending on the Lorentzian broadening used). I only had to edit 2 lines of code within optic.F90.

I hope this helps, and would be interested to know if you think I have made an error.

Best,
LP

P.S. I should also note that I am using version 6.8.1.

I am not much familiar with the occupancies in the ddk file.

Probably this post should go to the section of Proposed code modifications.