The d-d transition spectrum and Cu(II)-N bonds of [Cu(2,2′-bipyridine)2 (saccharin)] (saccharin) · 3 H2O

Following a recent upsurge of interest in saccharin complexes system, we have synthesized several saccharin mixed ligand complexes and attempt to discussed them. In this work, the d-d transition spectrum of the title compound crystal have been determined and it is explained with scaling radial theory of non-free ions which was proposed by our laboratory. However, the absorption position of d-d transitions of the title compound are at 10474, 12435, 13814, 15627 cm⁻¹. With data in the work of Brown and Shannon, Cu(II)-N bonds of the title compound are discussed and it shows that the coordination ability of saccharin in to copper(II) ion is weaker than that of 2,2′-bipyridine, but more stronger than that of a water molecule.