Combined N, N-isomers in the crystal structure of [1,8,9,10-tetrahydro-1,3,6,8-tetramethyl-dibenzo [c,m] dipyrazolo [3, 4-f:4', 3'-j]-[1,2,5,8,9,12] hexaazacyclotetradecinate-(2-)-N4,N9,N14 and 15 ; N20]-nickel

The authors have made an x-ray structural investigation (R = 0.053) of the complex of nickel with [1,2,5,8,9,12]-hexaazacyclotetradecine. In both independent molecules A and B the Ni atom is coordinated via the vertices of a distorted square by two amino atoms N am (Ni-N = 1.86 A) and two N azo atoms of both azo groups (Ni−N = 1.80-2.01 A) of the 14-membered macroheterocyclic ligand. The form of the macrocycle in A and B is a symmetrical saddle