Two novel one-dimensional polymeric cyano-bridged platinum(II) complexes of N-(2-hydroxyethyl)-ethylenediamine (hydeten), [M-II(hydeten)Pt(CN)(2)(mu-CN)(2)](n) (M-II = Zn-II (1) and Cd-II (2)), were synthesized and characterized by physico-chemical methods (elemental analysis, IR spectroscopy and thermoanalytical measurements) and X-ray diffraction. Thermal behaviours of 1 and 2 were followed using TG and DTA (DSC) techniques. The ID chain structures of I and 2 were verified by X-ray diffraction studies. According to the positions of the bridging cyano groups, in complex I the polymeric chains are built up via the 2,2-CT type, while in complex 2 the polymeric chains are built up via the 2,2-TT type. (C) 2007 Elsevier Ltd. All rights reserved.