Crystal and molecular structure of bis[dimethylbis(pyrazol-1-yl)gallato]nickel(II)

Abstract

Crystals of the title compound are monoclinic, a= 8·530(6), b= 17·939(10), c= 7·415(6)Å, β= 106·88(7)°, space group P2₁/c, Z= 2. The structure was determined from diffractometer data by Patterson and Fourier syntheses, and refined by full-matrix least-squares methods to R 0·049 for 1352 observed reflexions. The whole molecule is in a pseudo-chair conformation with the two six-membered Ga–(N–N)₂–Ni rings in boat conformations. The nickel atom lies on a crystallographic centre of symmetry in the middle of a planar arrangement of four nitrogen atoms. Mean dimensions are: Ga–N 1·977, Ni–N 1·895, Ga–C 1·944, N–N 1·355, C–N 1·333, C–C 1·377 Å; N–Ga–N 91·6, Ga–N–N 120·5, C–Ga–C 126·9, N–Ni–N (chelate angle) 92·4, N–Ni–N (non-chelate angle) 87·6, Ni–N–N, 124°.