Python script to calculate Wannier occupation matrix from Maximally localized Wannier functions.

Rotating the DFT occupation matrix using the unitary matrix calculated by Wannier90 to obtain Wannier occupation matrix:

wanocc.py -seed_name test -spin unpolarized -bnd_exc 5-12 -dis

See all option by wanocc.py -h

• seed_name, seed name for all files. Default = "wannier90".

• dis, enable subspace selection. Default = False
• spin, which spin channel to calculate? Default = unpolarized. Choose from: up/down/unpolarized
• bnd_exc, which bands to exclude. Default = 'empty'. Format "10-12 15"
• v, verbose mode, print out charge on WFs in home cell. Default = False

1. U matrix:seed_name_u.mat

   [Optional] subspace selection: seed_name_u_dis.mat

   [Optional] spin polarization: seed_name_up[dn]_u_dis.mat

2. DFT occupation matrix is read from seed_name.xml [from Quantum espresso]

The Wannier occupation matrix will be print in seed_name_occ.mat with the following format:

• First line: comment
• Second line: number of wannier functions
• Third line: number of R lattices
• Forth line to EOF: 1st WF index | 2nd WF index | R1 | R2 | R3 | Occupaiton (real) | Occupation (imag).