The accessible parameter domain consisted of varying options for the A + , B 2+ and X - 3 components of the HOIP, where A is a molecular cation (11 options), B is a divalent metal (29 options), and X is a halogen (4 options). Together, a total of 1276 initial compositions were considered. Körbel et al. successively subjected the compositions to increasingly stringent stability filters via high-throughout computation, until only 111 stable candidates remained, for which the band gap, E g , and effective mass, m * , were finally calculated.