[diegoperini]

> A reasonable approximation for a crystalline structure is balls – point masses – connected by springs, where the springs are covalent bonds, plus electrostatic effects between point charges.

Thanks! This is a great analogy.

[infinite8s]

This is the model used by most chemical simulation codes (that don't account for quantum chemistry). See for example the LAMMPS simulation software (https://lammps.sandia.gov/)

[adw]

If anything I wrote has been original, it would have been a big red flag :-)