Tris­(μ₄-azepane-1-carbodi­thio­ato)bis­(μ₃-azepane-1-carbodi­thio­ato)-μ₉-bromido-tetra-μ₂-bromido-octa­copper(I)­copper(II)

The reaction of Cu(Hm-dtc)₂ (H₂m-dtc is azepane-1-carbodi­thioic acid), CuBr₂ and methyl iso­thio­cyanate yielded the title mixed-valence nona­nuclear Cu^I/Cu^II compound, [Cu₉Br₅(C₇H₁₂NS₂)₅] or [Cu^I₈Cu^IIBr₅(Hm-dtc)₅], encapsulating a bromide anion in the center of the Cu₉Br₄S₁₀ cluster cage. The cage consists of a mononuclear Cu^II unit [Cu(Hm-dtc)₂], three μ₄-bridging Hm-dtc⁻ ligands, eight Cu^I ions with distorted tetra­hedral or trigonal pyramidal coordination geometries and four μ₂-bridging bromide anions. The incorporated central bromide anion inter­acts with nine Cu ions with shorter Cu—Br separations than the sum of the van der Waals radii for Cu and Br.