Vibrational spectra and force constants of periodates with ordered perovskite structure

Abstract Synthesis and vibrational spectra of some new periodates with ordered perovskite structure are reported. Force constants of the IO 6 5− octahedron are calculated using a simple UBFF. The differences between the force constants are explained by considering the cations in the lattice of A 2 BI 7+ O 6 ( A = Ba 2+ , Sr 2+ ; B = Li + , Na + , K + , Ag + ).