Review: New simple material model versus Goldschmidt's tolerance factor formalism

Abstract

ABSTRACTHigh fidelity modeling of a wide range of Perovskite material properties have recently been reported using correlated coordinated “effective” temperature dependent ion properties, radii and polarizability, as developed within an evolving “new simple” material model (NSMM). Here, we summarize NSMM developments. Within the range of NSMM reported A1+ and B5+ Perovskite ion properties, where A is Ag, Na, K, Cs, or Rb and B is Nb, Ta or U, we compare Perovskite modeling using Goldschmidt's tolerance factor (GTF) formalism, a correlation relation, with the evolving NSMM. Although spreadsheet calculations using NSMM are slightly more complicated than those for GTF, NSMM provides significant improvement with regard to fidelity of room temperature: (a) determination of lattice parameter and volume; and (b) structure determination, cubic versus non-cubic; as well as (c) extends such fidelity of (a) and (b) over large temperature ranges. Through incorporation of the Clausius – Mossotti relation (CMR), NSMM provides determination of: (a) temperature dependent dielectric properties; (b) polarization induced structural phase transition temperature(s), including determination of Curie temperature, and Curie constant at least for structures changing from to another crystal system; and, (c) importantly relate temperature and frequency dependent ion properties, radii and polarization, to Maxwell's conduction equation.