Structural characterisation of [Pt(NH3)(4)](2)[W(CN)(8)] [NO3]center dot 2H(2)O donor-acceptor complex

The bimetallic [Pt(NH3)(4)]2[W(CN)(8)] [NO3]. 2H(2)O is characterised by si ngle-crystal X-ray diffraction [S.G.P2(1)/m(11), a = 8.0318(7), b = 19.122( 2), c = 9.0812(6) Angstrom, Z = 2]. All platinum centres have the square-pl ane D-4h geometry with average dimensions Pt(1)-N 2.042(2) and Pr(2)-N 2.03 7(10) Angstrom. The octacyanotungstate anion has the square-antiprismatic D -4d configuration with average dimensions W(1)-C 2.164(13), C-N 1.140(12), W(1)-N 3.303(5) Angstrom. The structure exhibits two different mutual orien tations of Pt versus W units resulting in Pt(2)-W(1), W(1)* separations of 4.77(2), 4.55(2)* and Pt(1)-W(1) of 6.331(8) Angstrom. A centrosymmetric st ructure reveals groups of two distinct columns: the first is formed by inte rcalated NO3- between parallel [Pt(1)(NH3)(4)](2+) planes and the second co nsists of [W(CN)(8)](3-) interlayered by, parallel to square faces of W-ant iprisms, [Pt(2)(NH3)(4)](2+). The structure is stabilised through a three-d imensional hydrogen bond network via nitrogen atoms of cyanide ligands, hyd rogen atoms of NH3 ligands, water molecules and oxygen atoms of NO3- counte ranions, The vibrational pattern and the range of v(CN) frequencies attribu table to the electronic environment of W(V) and W(IV) are consistent with t he ground state Pt(II) <-> W(V) charge transfer. (C) 2000 Elsevier Science B.V. All rights reserved.