Structure and Luminescent Properties of Complex Compounds of Tellurium(IV) with Ammonium Bases

Using tellurium(IV) complex compounds with outer-sphere ammonium cations as an example, we have studied the interrelation between their geometric structure and spectral-luminescent properties. In the series of compounds of tellurium(IV), which are characterized by the island octahedral coordination of Te(IV) ions, the luminescence intensity has been found to depend on the degree of distortion of the coordination polyhedron of the Te(IV) ion, the position of the A band in diffuse reflection spectra, and the energy of the luminescence transition (3) P (1) -> (1) S (0) of the tellurium(IV) ion. We have revealed that the considered Te(IV) complexes possess reversible thermochromic properties.