Dielectric and optical studies of phase transitions in [(CH3)2NH2]5Cd2CuCl11 crystal

Single crystals of [(CH3)2 NH2]5Cd2CuCl11 have been grown and their dielectric and optical properties have been studied. Electric permittivity, losses and linear optic birefringence measurements have shown that the obtained new crystal is isomorphous with the original one – [(CH3)2 NH2]5Cd3Cl11. Phase transitions were observed at 175 K (continuous) and 120 K (first order). It means that partial replacing of cadmium atoms by copper ones does not change the structure and the heavy Cd2CuCl11–2 anions do not influence significantly the interaction of dimethylammonium cations. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)