Low valent phosphorus in the molecular anions [P5Se12](5-) and beta-[P6Se12](4-): phase change behavior and near infrared second harmonic generation

Abstract

The caesium salts of the novel molecular anions [P5Se12](5-) and [P6Se12](4-) are phase change materials and exhibit near infrared, non-linear optical second harmonic generation; [P5Se12](5-) is a coordination complex with an octahedral P3+ center chelated by two [P2Se6](4-) ligands whereas [P6Se12](4-) features a [P-2](4+) dimer chelated by two [P2Se6](4-) ligands.