How to define a chemical bond computationally?

I'm working with an amorphous system. With oxygen, my system has both covalent and ionic bond forming cations. I utilise the [Wannier centre](https://en.wikipedia.org/wiki/Wannier_function) to define a covalent bond, and my theory is that if the Wannier centre is near to the line connecting the cation and anion, it is a covalent bond.


However, this method fails to identify an ionic bond as there is no region of high electronic charge density which can be localized to obtain Wannier center. How can an ionic bond be defined using a computational technique?


