Roman N. - 2014-01-10

Dear all,
ok, here I summarize all results below. All calculations (in Wien2k and in Elk) are done with Rmt=2.50au, 16x16x16kp, rgkmax=9.0, gmaxvr=14.0, lmaxapw=10, Gauss smearing with swidth=0.001Ha.

Optimal lattice parameters based on Murnaghan EOS and calculated E(alat) for alat=5.8,5.9…6.5au.
Wien2k
4p in core, all linearization energies are allowed to optimize – 6.13au (LDA), 6.30au (PBE)
4p in valence, all linearization energies are allowed to optimize – 6.30au (PBE)
4p in valence, all linearization energies are fixed (except one of LO of p state) – 6.13au (LDA), 6.30au (PBE)
Elk
Default species file (4p in valence, LAPW) – 6.07au (LDA)
Default species file (ecvcut=-3.0, 4p in core, APW) – 6.06au (LDA), 6.25au (PBE)
All linearization energies are fixed to Wien2k final ones (LAPW, 4p in valence, semi-core energies are allowed to adjust (Lars’s suggestion)) – 6.07au (LDA), 6.26au (PBE)

It looks like modifications of energies affect very little or does not affect at all EOS (which is great!), but there is still a disagreement between Wien2k and Elk lattice parameters by about 0.6-1.0%.

Thank you, Lars, for noticing the difference in basis set (I really overlooked LAPW). I modified Sn species file accordingly (please see it below), please tell me if there are errors.
Energy zero is set as the average potential in the interstitial in Wien2k too. Furthermore, as the Fermi energy has the same reference (energy zero), matching energy values in species file with respect to Ef would be equivalent to matching them with respect to energy zero.
With best regards,
Roman

Sn.in file:
'Sn' : spsymb
'tin' : spname
-50.0000 : spzn
216395.0920 : spmass
0.282843E-06 2.5000 45.4746 600 : sprmin, rmt, sprmax, nrmt
17 : spnst
1 0 1 2.00000 T : spn, spl, spk, spocc, spcore
2 0 1 2.00000 T
2 1 1 2.00000 T
2 1 2 4.00000 T
3 0 1 2.00000 T
3 1 1 2.00000 T
3 1 2 4.00000 T
3 2 2 4.00000 T
3 2 3 6.00000 T
4 0 1 2.00000 T
4 1 1 2.00000 F
4 1 2 4.00000 F
4 2 2 4.00000 F
4 2 3 6.00000 F
5 0 1 2.00000 F
5 1 1 1.00000 F
5 1 2 1.00000 F
2 : apword
0.0680 0 F : apwe0, apwdm, apwve
0.0680 1 F : apwe0, apwdm, apwve
0 : nlx
5 : nlorb
0 2 : lorbl, lorbord
-0.0937 0 F : lorbe0, lorbdm, lorbve
-0.0937 1 F
1 2 : lorbl, lorbord
0.0758 0 F : lorbe0, lorbdm, lorbve
0.0758 1 F
2 2 : lorbl, lorbord
0.0393 0 F : lorbe0, lorbdm, lorbve
0.0393 1 F
1 3 : lorbl, lorbord
0.0758 0 F : lorbe0, lorbdm, lorbve
0.0758 1 F
-2.8987 0 T
2 3 : lorbl, lorbord
0.0393 0 F : lorbe0, lorbdm, lorbve
0.0393 1 F
-0.6177 0 T