Magnetic properties of new copper(II) and [copper(II)](3)-manganese(II) complexes of [14]N-4 macrocyclic oxamides

Four new complexes of [14]N-4 macrocyclic oxamides, namely [CuL1], [CuL2]: [(CuL1)(3)Mn](ClO4)(3) and [(CuL2)(3) Mn](ClO4)(3) [L-1 and L-2 are the dia nions of 2,3-dioxo-5,6: 3,14-dibenzo-7,12-bis(ethoxycarbonyl)-1,4,8,11-tetr aazacyclotetradeca-7,11-diene (H2L1) and 2,3-dioxo-5,6:3, 14-dibenzo-9-meth yl-7,12-bis(ethoxycarbonyl)-1,4,8,11 -tetraazacyclo-tetradeca-7,11-diene (H 2L2), respectively], have been prepared and characterized. The observed mag netic susceptibilities of the [(CuL1)(3)Mn] (ClO4)(3) complex over the cn. 2-300 K range have been fitted to theoretical equations based on the Heisen berg spin Hamiltonian (H) over cap = -2J (S) double under bar(Mn)((S) over cap(Cu1) + (S) over cap(Cu2) + (S) over cap(Cu3)) and molecular field appro ximation. The results indicated that both the intramolecular and intermolec ular magnetic interactions are antiferromagnetic with J(CuMn) = -19.8 cm(-1 ) and zJ' = -1.41 cm(-1).