Crystal structure of bis-(η(5)-cyclo-penta-dien-yl)(2,3-di-ethyl-butane-1,4-di-yl)hafnium(IV).

The title compound, [Hf(C5H5)2(C8H16)], proves a structural motif of hafna-cyclo-pentane besides the coordination of two cyclo-penta-dienyl ligands in an η(5)-fashion. The hafna-cyclo-pentane ring has a twist conformation and is substituted by two ethyl groups in the β,β'-positions, which are trans orientated to each other. One cyclo-penta-dienyl ring and one ethyl group are each disordered over two positions with site-occupancy ratios of 0.679 (15):0.321 (15) and 0.702 (18):0.298 (18), respectively.