Polarised absorption, emission and reflectivity of the one-dimensional compound BaPt(CN)44H2O

Abstract

Linearly polarised transmission, absorption, fluorescence excitation, emission and reflectivity spectra have been measured for crystals of the one-dimensional chain compound BaPt(CN)₄4H₂O at temperatures from 300 to 9 K. The broad reflectivity peak centred near 23 000 cm^–1 scarcely varies in width with changing temperature. It is shown that the fluorescence excitation spectrum is a good guide to the absorption up to 25 000 cm^–1, while the temperature variation of the emission spectrum reveals the influence of self-absorption at higher temperatures. The E⊥c absorption varies remarkably with temperature, both in frequency and intensity, probably because the Pt—Pt spacing decreases with decreasing temperature, due to anharmonicity in the phonon spectrum.