While processing large set of .cif files I encountered an interesting issue regarding density calculations. By looking at the source of the Crystal.calculated_density command (look below), I found it interesting that it doesn't proceed with calculations if certain Z' criteria is not met. Am I missing something, as I thought that you only need Z (and not Z' values) for crystallographic density calculations.
Can anyone elaborate on this?
if self.z_value is None or self.z_prime is None or self.z_prime == 0.0: