How to convert the information from system.am  to amulet.ini  and impurity_X.ini  files?

After an execution of the wannier_ham.x program (part of the Quantum Espresso) two files will be created. The first file is hamilt.am and it is in the format compatible with the AMULET code. The second file is system.am and it contains an information about the Wannier functions used for the Hamiltonian construction. The system.am looks like this (example of NiO):

# This file was generated on: 26Feb2016 1:35:53 


&hash
1456446953

&cell
7.926648360
0.00000 0.50000 0.50000
0.50000 0.00000 0.50000
0.50000 0.50000 0.00000

&atoms
2
Ni 0.00000 0.00000 0.00000
O 0.50000 0.50000 0.50000

&nelec
14.00

&efermi
11.2814

# Basis description:
# dim, nblocks
# atom_sym, atom_num, l_sym, block_dim, block_start, orbitals(1:block_dim)
&basis
8 2
Ni 1 d 5 1 7 8 6 9 5
O 2 p 3 6 3 4 2

Partially, the information from this file is used to setup properly amulet.ini and impurity_X.ini files. The information you need for the amulet.ini file is in &nelec section, which is a number of valence electrons for the Hamiltonian in the Wannier function representation (14=2p2O+4s2Ni+3d8Ni). This number goes to a ntotal token of amulet.ini file. The value of the chemical potential of &nelec section goes to mu token:

  TinK = 500
L = 1000
ecut = 500

istart = 1
niter = 7
alpha = 0.9

mu = 11.28
ntotal = 14

The information from the &basis section of system.am file is used to setup the impurity_X.ini file. As we regard only Ni atom as correlated, then there is one type of impurity and this file must be named impurity_1.ini. The data you need belongs to the Ni atom. The name of atom (atom_sym in system.am) goes to a token name in the impurity_1.ini. block_dim corresponds to a nlm token (fourth column). block_start is a himppos token.

  name = Ni
nlm = 5
himppos = 1

U = 6
J = 0.9
DC_type = sfll

solver = ct-qmc-w
nqmc = 640000

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