X-ray study of [Cu(NH3)4](ReO4)2-[Cu(NH3)2(μ-ReO4)2]n transformation

Resumo

The X-ray in-situ study of [Cu(NH₃)₄](ReO₄)₂ complex salt is carried out on heating up to 500 K. The product obtained at this temperature is a new crystalline phase [Cu(NH₃)₂(μ-ReO₄)₂]_n with the following unit cell parameters: a = 14.7523(3) Å, b = 5.8559(1) Å, c = 5.6290(1) Å, β = 111.387(1)°, V = = 452.799(2) ų, space group C2/m, Z = 2, d_x = 4.386 g/cm³. The coordination polyhedron of the Cu atom is a distorted octahedron formed by two nitrogen atoms (Cu–N 2.195 Å), and four oxygen atoms (Cu–О 2.306 Å). The structure consists of infinite [Cu(NH₃)₂(μ-ReO₄)₂]_n chains, the shortest N(H)…O distances between the chains being 2.82 Å.