Interaction of hydrogen and hydrocarbons with transition metals. Neutron diffraction study of di-.mu.-hydrido-decacarbonyltriosmium, (.mu.-H)2Os3(CO)10, containing a four-center four-electron hydrogen-osmium (H2Os2) bond

摘要: The low-temperature crystal and molecular structure of (..mu..-H)/sub 2/Os/sub 3/(CO)/sub 10/ has been determined by neutron diffraction techniques. Lattice parameters at 110/sup 0/K for the centrosymmetric triclinic space group P1 are a = 8.499(4)A, b 9.029(4)A, c 11.714(5)A, ..cap alpha.. 91.59(1)/sup 0/, ..beta.. 98.98(2)/sup ..gamma.. 117.33(2)/sup V 783.7A/sup 3/. triosmium fragment may be viewed as forming an isosceles triangle with one short two long metal--metal distances. osmium--osmium bond, which is symmetrically bridged hydrogen atoms, length 2.683(1)A, while nonbridged bonds have equal lengths 2.814(1) 2.815(1)A. mean osmium--hydrogen bond distance 1.845(3)A. A bonding scheme presented supports formulation metal--hydrogen interaction four-center, four-electron bond. 4 figures, 5 tables.