A Dinuclear Holmium(III) `Carbons Apart' Carborane Cluster, [C₃₄H₉₂B₈Cl₄Ho₂Li₂N₆Si₄].C₁₀H₈

The title compound (1), 1-[([mu]-Cl)₂Li(TMEDA)]-2,2',4,4'-(SiMe₃)₄-5,5',6,6'-[([mu]-H)₄Ho(TMEDA)([mu]-Cl)₂Li(TMEDA)]-1,1'-commo-Ho(2,4-C₂B₄H₄)₂.C₁₀H₈ (where TMEDA is tetramethylethylenediamine, bis[[mu]-2[kappa]²H^B5,H^B6: 3(2,3,4,5,6-[eta])-2,4-bis(trimethylsilyl)-2,4-dicarba-nido-hexaborate(6)]tetra-[mu]-chloro-1:2[kappa]⁴Cl;3:4[kappa]⁴Cl-tris(N,N,N',N' -tetramethyl-1,2-ethanediamine)-1[kappa]²N,N';2[kappa]²N,N';4[kappa]²N,N'-1,4- dilithium-2,3-diholmium naphthalene solvate, crystallizes in the triclinic space group P. The cluster consists of a Ho^III `carbons apart' carborane bent-sandwich complex bridging almost symmetrically to an exo-polyhedral Li(TMEDA) unit via two Cl atoms and, via two B-H(terminal) groups of each opposing C<sub>2</sub>B<sub>3</sub> face, to an exo-polyhedral Ho<sup>III</sup>(TMEDA) unit that is also linked to another exo-polyhedral Li(TMEDA) group with two Ho-Cl-Li bridges. The centrally located Ho atom is almost symmetrically bonded to two opposing `carbons apart' C₂B₄ carborane cages with Ho1...Cnt1 2.340, Ho1...Cnt2 2.349Å, Cnt1...Ho1...Cnt2 130.2, Cnt1...Ho1...Cl1 107.1, Cnt1...Ho1...Cl2 107.1, Cnt2...Ho1...Cl1 109.1, and Cnt2...Ho1...Cl2 109.1°, where Cnt is the centroid of the C₂B₃ face of each.

-1