Total energy result conpared with VASP is so huge

Posted on : October 02, 2018 (Tue) 21:52:07

by C.R. Fu

Dear Hitoshi,
The total energy of bcc Fe in sample is -2522 Ry.But in VASP calculation, the total energy of two Fe atoms in a bcc cell is about -17 eV. What's more, the vlume depensence of Total enegy seems can't be fitted by BM EOS well.

[Re:02] Total energy result conpared with VASP is so huge

Posted on : October 13, 2018 (Sat) 15:23:45

by C.R. Fu

Dear Hitoshi,
Happy to see your reply.
It's my mistake. I ignore the total energy is an absolute value, and I fit the EOS directly with the absolute value as I do with VASP. Absolute value of AkaiKKR is much larger than that of VASP, so that the minimum of E-V curve seems not obvious.
Then I fit the EOS with E-E0, the EOS can be fitted by BM EOS well now.

by C.R. Fu

[Re:01] Total energy result conpared with VASP is so huge

Posted on : October 08, 2018 (Mon) 14:46:36

by Hitoshi GOMI

Hello C.R. Fu,

> The total energy of bcc Fe in sample is -2522 Ry.But in VASP calculation, the total energy of two Fe atoms in a bcc cell is about -17 eV.
It is quite natural. The absolute value of the total energy strongly depends on the calculation setting.

> What's more, the vlume depensence of Total enegy seems can't be fitted by BM EOS well.

Please provide enough information to reproduce: input file of AkaiKKR, list of volumes (lattice parameters) you calculated, the formula of the BM EOS and etc.

Hitoshi GOMI