Comparative study of excitonic structures and luminescence properties of Bi₄Ge₃O₁₂ and Bi₁₂GeO₂₀

Abstract

Abstract Measurements of reflection, emission‐excitation, luminescence decay kinetics, and X‐ray photoelectron of Bi 4 Ge 3 O 12 and Bi 12 GeO 20 crystals have been performed, in addition to relativistic molecular orbital calculations. Both materials consist of the same elements but form different crystal structures. Based on the obtained results, the excitonic reflection structures and luminescence properties of Bi 4 Ge 3 O 12 and Bi 12 GeO 20 are discussed in comparison with each other. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)