CRYSTAL-STRUCTURE, THERMAL-EXPANSION AND DIELECTRIC-PROPERTIES OF MONOCLINIC ETHYLENEDIAMMONIUM BIS(HYDROGENSUCCINATE), H3N(CH2)2NH3(HC4H4O4)2

Large single crystals of optical quality of monoclinic ethylenediammon ium bis(hydrogensuccinate) were grown from aqueous solutions. An X-ray structure analysis yielded space group P2(1)/c, a1 = 5.358(1), a2 = 1 2.947(3), a3 = 9.608(2) angstrom, alpha2 = 95.26(2)-degrees, Z = 2, rh o(calc) = 1.483(1); rho(obs) = 1.481(2) g cm-3. This acid succinate sa lt can be classified as type B2 salt. The structure contains short hyd rogen bonds between adjacent succinate ions which form periodic bond c hains along [201BAR]. The length of the short hydrogen bond is 2.581(1 ) angstrom. The chains are interconnected by hydrogen bonds via the et hylenediammonium cations forming a three-dimensional network. The ther mal expansion was studied between 230 and 350 K. The tensor of thermal expansion exhibits a very large anisotropy (alpha(max) - alpha(min) = 459 . 10(-6) K-1). Further, the dielectric constants between 10 KHz a nd 10 MHz and the indices of refraction in the visible spectrum were d etermined.