Tetra-μ 3 -selen-ido-1:2:3κ 3 Se ;1:2:4κ 3 Se ;1:3:4κ 3 Se ;2:3:4κ 3 Se -tetrakis-[(η 5 -methyl-cyclo-penta-dien-yl)molybdenum(III)](6 Mo-Mo ).

The title cluster compound, [Mo ₄ (η ⁵ -C ₅ H ₄ Me) ₄ (μ ₃ -Se) ₄ ], was synthesized from the reaction of [Mo(η ⁵ -C ₅ H ₄ Me)(CO) ₃ ] ₂ with grey selenium in refluxing xylene solution under a nitro-gen atmosphere. The complete cluster is generated by a crystallographic twofold axis and contains an Mo ₄ Se ₄ cubane-like core surrounded by four η ⁵ -methylcyclo-pentadienyl ligands. In the core, the four molybdenum atoms are connected to each other to form a tetra-hedron, with a selenium atom capping each face. The Mo-Mo bond lengths vary from 2.9857 (5) to 3.0083 (3) Å and the Mo-Se separations range from 2.4633 (4) to 2.4693 (5) Å.
(© Ouchi et al. 2023.)