[QE-users] Different ELF values with QE 7.0

[Roman Lucrezi]

Hi everybody,

recently I used QE v.7.0 to recalculate the 3D electron localization 
function (ELF) in a system I had already worked on with QE v.6.5, and 
obtained quantitatively quite different results: e.g. for specific 2D 
cuts I get differences in the range of 0 to 0.25 (for 
ELF(v.7.0)-ELF(v.6.5)), where the v.7.0 results are always higher.

I have rerun everything with the exact same input files, trying v.6.5, 
v.6.7MaX and v.7.0: v.6.5 and v.6.7MaX give the same results, v.7.0. is 
different as described above.

For each version I ran a non-polarized (nspin = 1) scf calculation with 
scalar-relativistic PBE ONCV pseudos, the system is metallic and I used 
a mp smearing. After that, I used pp.x for the ELF and an XSF file with 
this input (and varying prefixes):

&inputPP
    prefix   = 'v6_5',
    outdir   = './tmp'
    plot_num = 8
    filplot  = 'v6_5.elf.dat'
/
&plot
    iflag         = 3,
    output_format = 5
    fileout       = 'v6_5.elf.xsf'
/

Do you have any idea on what could cause this discrepancy? I saw in the 
release notes that there were some problems with ELFs in the 
spin-polarized case, and there is also a line for v.7.0, saying that the 
spin-UNpolarized ELFs were grossly wrong in v.6.8. Does this affect only 
v.6.8, or each version up to v.6.8, meaning that only v.7.0 gives 
correct results?

Kind regards,

Roman Lucrezi
Institute of Theoretical and Computational Physics
Graz University of Technology, Austria