PREPARATION AND THERMAL-PROPERTIES OF THE COMPLEXES CRYSTALLIZING FROM THE SYSTEM ZN(II)-EN-[NI(CN)4](2-)-H2O

The seven complexes [Zn(en)3][Ni(CN)4].H2O (I), [Zn(en)3][Ni(CN)4] (II ). Zn(en)2Ni(CN)4 (III), Zn(en)2Ni(CN)4.2H2O (IV), [Zn(en)2Ni(CN)4Zn(e n)][Ni(CN)4].3H2O (V), [Zn(en)2Ni(CN)4Zn(en)][Ni(CN)4] (VI) and Zn(en) Ni(CN)4 (VII) were isolated from the system Zn(II)-en-[Ni(CN)4]2--H2O. They were studied with methods of elemental analysis, IR spectroscopy and X-ray powder diffractometry. The thermal stability and stoichiome try of thermal decomposition were studied with a derivatograph. Upon h eating, reactions according to the following scheme were observed: [GR APHICS] The structural changes during the individual processes are dis cussed on the basis of the known crystal structures of I, II, III, V a nd VII.