Electrochromic multilayer films consisting of polyoxometalate (POM) cluster R-K10[P2W17O61]17H2O (P2W17), copper(II) complex [CuII(phen)2](NO3)2 (phen = 1,10-phenithroline), and iron complex [Fe II(phen)3](ClO4)2 were fabricated on silicon, quartz and ITO substrates by layer-by-layer self-assembly method. The multilayer films, PSS/CuII(phen)2/[(P2W17/CuII(phen)2)]n and PSS/FeII(phen)3/[(P2W17/FeII (phen)3)]n were characterized by UV-vis spectra, X-ray photoelectron spectra, cyclic voltammetry (CV), chronoamperometric (CA) and in-situ spectral electrochemical measurements. The interesting feature of the electrochromic film is its adjustable color by reduction of both transition metal complex and polyoxometalate at different potentials. The multilayer films also exhibit high optical contrast, suitable response time and low operation potential due to the presence of mono-lacunary-substituted polyoxometalate and transition metal complex. This is the first example that the color of electrochromic film can be adjustable, which gives valuable information for exploring new electrochromic materials with tunable colors.

The compound [NH3(CH2)2NH2(CH2)2NH3]2[Mo9O30] was synthesized at 170 °C via hydrothermal techniques from the starting materials of Na2MoO4H2O, NH2(CH2)2NH(CH3)2NH2, and H2O. The compound crystallizes in the space group C2/c of the monoclinic system with a = 21.308(4)A, b = 9.234(2)A, c = 19.195(4)A, β = 120.27(3) γ, V = 3261.9(11)A3, Z = 4. Two novel and symmetrically related helices coexist in the centrosymmetric solid, in which the two kinds of helices appear in the left-handed and right-handed enantiomorphs, respectively. This is the first example of a helical chain structure consisting of only molybdenumoxide building blocks. The central axis about each helical chain is a 2-fold screw axis.

A new layered vanadium phosphate {[(phen)VIVO]2(VV2O5)(HPO4)}n has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, and single-crystal X-ray diffraction. This compound crystallized in the monoclinic space group P2/c with a ) 9.979(2) , b ) 9.886(2) , c ) 15.298(3) , ) 102.86(3)

The rst O,O -bonded metal-stabilized sulnate, Mn(2-sinic-O,O )(DMSO)2 (2-sinic = 2-sulnato-nicotinate) has been isolated and structurally characterized to show a novel onedimensional chain structure containing both the enantiomers of the subunit Mn(2-sinic)(DMSO)2 .