INTERACTION BETWEEN METAL-IONS AND ZWITTERIONIC SPECIES - CRYSTAL ANDMOLECULAR-STRUCTURE AND SPECTROSCOPIC CHARACTERIZATION OF [CU(MTPA)(2)(NO3)(2)] (3-METHYL-1,2,3-TRIAZOLO[1,5-A]PYRIDINIO)]ACETATE)

The crystal and molecular structure of [Cu(mtpa)(2)(NO3)(2)] (mtpa = ( 3-methyl-1,2,3-triazolo[1,5-a]pyridinio)]acetate) have been determined by X-ray diffraction methods. The crystal structure is built up of di screte [Cu(mtpa)(2)(NO3)(2)] entities. The stereochemistry displayed b y the copper atoms, which lie on symmetry centres, can be described as elongated rhombic octahedral (CuO2O'O-2 ''(2) chromophore), with bide ntate nitrato groups involved in off-the-z-axis coordination. Spectros copic properties are interpreted on the basis of the above stereochemi stry. Copyright (C) 1996 Elsevier Science Ltd