The group 6 metal halide clusters, [M₆X₈Y₆]^2- (M = Mo, W; X, Y = Cl, Br, I) have been extensively studied due to their unique photochemistry and long-lived excited states. A limited number of divalent metals salts of these clusters are known including lead, mercury, and cadmium. The only first-row transition metal examples are the iron and cobalt salts of [W₆Cl₈Cl₆]^2-. All of the known metals salts are prepared by the direct solid-state reaction of the respective metal halide and the corresponding molybdenum or tungsten halide, typically requiring reaction temperatures in 500 - 800 °C range.

We have prepared and determined the structures of a series of DMF-solvated metal cation salts of the molybdenum chloride cluster, [M(DMF)₆][Mo₆Cl₁₄], where M = Co, Ni, Cu, Zn, Ca, Sr, and Cd. These salts can be cleanly converted to the solvent-free metal cluster salt by heating under vacuum to 250-300 °C. Preliminary results indicate formation of compounds isostructural to the lead and mercury cluster salts. We are in the process of fully characterizing the resulting products by powder X-ray diffraction and Raman spectroscopy.

Displacement ellipsoid diagram of the metal complex salt [Co(DMF)<sub>6</sub>][Mo<sub>6</sub>Cl<sub>14</sub>].

Displacement ellipsoid diagram of the metal complex salt [Co(DMF)₆][Mo₆Cl₁₄].

Colleen Bungard

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