A structure with trigonally and tetrahedrally coordinated CuIcations:rac-(acetonitrile)[2,2′-bis(1-propyl-1H-benzimidazol-2-yl)biphenyl]copper(I) bis(acetonitrile)[2,2′-bis(1-propyl-1H-benzimidazol-2-yl)biphenyl]copper(I) bis(perchlorate)

The asymmetric unit of the title salt, [Cu(C32H30N4)(C2H3N)][Cu(C32H30N4)(C2H3N)2](ClO4)2, contains two per­chlor­ate anions and two crystallographically distinct CuI complexes, viz. [Cu(L1b)(acetonitrile)]+ (A) and [Cu(L1b)(acetonitrile)2]+ (B), where L1b is 2,2′-bis­(1-propyl­benzimidazol-2-yl)biphenyl. The A and B cations exhibit approximate trigonal–planar and tetra­hedral coordination geometries, respectively. In the solid state, the ligand L1b is chiral but the crystal structure is a racemate. The cations form separate, enanti­omerically pure columns along the a-axis direction. Centrosymmetrically related alternating R and S columns of A and of B cations, centered about the planes y = 0 and y = {1 \over 2}, respectively, progress along the c-axis direction. The perchlorate ions, which form columns along the a-axis direction, are linked to the cations by C—H⋯O hydrogen bonds.