Crystal structure of Bis(2,2':6',2''-terpyridyl)cobalt(II) iodide dihydrate at 295 K and at 120 K

Abstract

The crystal structure of the title compound, [CO(C₁₅H₁₁N₃)₂] 12.2H₂O, has been determined by single crystal X-ray diffraction methods at 295 K and at 120 K, being refined by least squares to residuals of 0.051 and 0.035 respectively for 982 and 1024 'observed' reflections at these temperatures. Both structures are based on a P4₂/n tetragonal cell, a c. 8.9, c c. 19.4 Å, Z 2, in which only a quarter of the cation is independent, being located about a site of 4 symmetry. At room temperature (μ_off c. 3.2 BM) Co-N (central, distal) are 1.942(7), 2.104(5) Å diminishing to 1.912(5), 2.083(4) Å at 120 K, with μ_off c. 2.2 BM, corresponding to a fully populated low-spin ground state.