Preparation and structure of (Cu(pc))3(ReO4)2 and theoretical investigation of Cu(pc)(ReO4), Cu(pc)(ReO4)2, and (Cu(pc))3(ReO4)2

The compound (Cu(pc))3(ReO4)2 (pc = phthalocyaninato) has been prepared by electrocrystallization from a p-dichlorobenzene solution of Cu(pc) and [N(n-Bu)4][ReO4]. (Cu(pc))3(ReO4)2 crystallizes with one formula unit in the triclinic space group P1¯ with cell constants at T = 153 K of a = 12.6202(6) Å, b = 13.7596(7) Å, c = 14.0294(7)Å α = 64.6376(9)°, β = 64.2570(9)°, and γ = 66.0549(9)°. The molecular structure comprises a stack of three Cu(pc) rings; the Cu center in each peripheral ring has an attached ReO4 ligand, the Cu-O distance being 2.374(5) Å. The inter-ring distance is 3.1595(11) Å. Density functional theory calculations for Cu(pc)(ReO4) and Cu(pc)(ReO4)2 suggest that the ring-π states are the source of the electron donation to the ligands. Calculations for (Cu(pc))3(ReO4)2 suggest that the charges on the central and peripheral rings are nearly equal. For all three compounds the basic spin distributions are similar to each other and to those of other Cu(pc) systems. For (Cu(pc))3(ReO4)2 a localized, rather than an itinerant, description of the magnetism is indicated.