Crystal, molecular, and electronic structure of trans-bis[ethanone, 1-(2-hydroxyphenyl)-oximato]nickel(II)

The compound [Ni(apox)(2)], (where apex - denotes the anion of 2-hydroxyacetophenoneoxime, C8H8NO2), was prepared and studied by means of spectroscopic (IR, H-1 NMR, UV-Vis) measurements and theoretical calculations employing the Huckel method. The structure was determined by X-ray diffraction studies. The unit cell is monoclinic (space group P2(1)/c) with dimensions a = 7.845(1), b = 9.911(2), c = 19.371(2) Angstrom, beta=94.37(1)degrees and contains four formula units. Huckel investigations in comparison with the electronic excitation spectrum revealed that the two bands at 2.73 and 2.62 mu m(-1) can be characterised as MLCT, the band at 1.62 mu m(-1) as d-d transition, while the band at 2.14 cm(-1) has a mixed character of both MLC-IT and d-d transition.