Abstract
The origin and character of the variation of luminescence parameters at phase transitions in [N(CH3)4]2MnCl4 single crystals are studied. It is shown that the abrupt changes of spectral positions of luminescence and luminescence excitation bands, their intensities and decay time of emission take place at T 2 = 173 K. The experimental results are discussed in the model which relates the observed changes to the distortion of structural [MnCl4]2- tetrahedral complexes, which simultaneously manifested as luminescence centres in [N(CH3)4]2MnCl4 single crystals.