  Asceding interest of the scientific community in layered hybrid halide
perovskites (LHHPs) as materials for innovative photovoltaic and optoelectronic
applications led to unprecedented expansion of this family of compounds,
reaching now several hundred refined structures. Despite the unique structural
diversity of LHHPs, traditional approaches of describing their structures, such
as dividing into Dion-Jacobson (DJ) or Ruddlesden-Popper (RP) phases for mostt
structures are ambiguous and unquantifiable. Here, we introduced a quantitative
layer shift factor (LSF) for a univocal classification and quantitative
comparison of the structures. We also developed an algorithm for automatic
calculation of the LSF for such structures. We demonstrate the application of
the proposed approach for an analysis of correlations between LSF and band gap
to reveal "structure-property" relationships. Our study gives a simple and
useful approach to classify of either the layered perovskite-like structures or
other layered compounds composed of layers of vertex-connected octahedra as a
structural unit.
