iv_characteristics = nlread('pldos-Sn4S8-1e19-n-Vds0.64V-Vg-1.0V.hdf5', IVCharacteristics)[-1]
mp = iv_characteristics.results(
-1.0*Volt,
0.64*Volt,
[MullikenPopulation])[-1]
nlsave('mp_results.hdf5', mp)
m = nlread('mp_results.hdf5', MullikenPopulation)[0]
print(m.atomicCharge().sum())