Optical band gap studies of [N(CH3)4]2ZnCl4 single crystals on the paraelectric phase

A displacive modulation wave develops below the normal paraelectric phase at T<294 K, and the dependence of its wavelength on temperature, was studied. The results of the optical absorption and transmittances measurements performed in the fundamental absorption region of [N(CH3)4]2ZnCl4 (TMA-ZC) single crystals are analyzed and discussed. The single crystals of TMA-ZC of good optical quality were grown from seeded supersaturated solutions prepared from stoichiometric proportion of (CH3)4NCl and ZnCl2 at 304 K.