# title
Encapsulation of heavy transition metals in iodide clusters. Synthesis, structure, and bonding of the unusual cluster phase yttrium iodide-ruthenium (Y6I10Ru)

# abstract
The reaction of Y3Ru with YI3at 800950 C in a sealed Ta container affords Y7I12Ru and Y6I10Ru, the yield of the latter increasing with time or temperature. Y7I12Ru is isostructural withsc7C112B on the basis of Guinier powder data (R3, Z = 3, a = 15.4373 (7) , c = 10.6126 (6) ). The new structure type of Y6I10Ru was deduced from its lattice dimensions and symmetry and was refined with single-crystal X-ray diffraction data (PI, Z = 1; a = 9.456 (2) , b = 9.643 (2) , c = 7.629 (1) , a = 97.20 (2), = 105.04 (2), = 107.79 (2); R = 5.2, Rw= 6.7% for 1421 independent reflections, 2 55, Mo Ka radiation). The structure consists of Y6i12clusters centered by Ru and condensed into infinite chains through sharing of inner iodine (I1) atoms with the two adjoining clusters, viz., Y6Ii8Ii-i4/2Ru. The clusters are connected in the other two directions through the more typical Ii_alinkages at metal vertices. The nominal octahedral Y6Ru cluster shows a 0.21-A tetragonal compression, contrary to the usual behavior of ML6units with a tlu4HOMO. Charge-iterative extended Hiickel calculations show that the distortion originates with Y-Y interactions because of a negligible participation of the high-lying Ru 5p orbitals in the HOMO.  1989, American Chemical Society. All rights reserved.