I have a list of crystal structures and I use pymatgen “Structure” to read each crystal and I use the charge property function to get the charge of the crystal. But I thought I always get the zero for each crystal.
Did I do something incorrect in this manner? Because obviously, some are not charge neural. For example some materials have three metal elements in the formulas.
Charge is a property you give the structure object, not something intrinsic to a specific structure. It might have preferred charge states, but these require DFT calculations to find the relative energy orderings.
Just because a compound has 3 metal ions doesn’t mean it’s not charge neutral. There are plenty of known metallic compounds with multiple metallic elements such as the binary inter-metallics.