STRUCTURAL AND SPECTROSCOPIC STUDIES IN THE [M(C₆H₆N₃S₂)₂] [M= Cu(II), Ni(II)] COMPOUNDS. J. L. Pizarro, J. García-Tojal, L. Lezama, M. I. Arriortua, Depts. de Mineralogía-Petrología y Química Inorgánica. Universidad del País Vasco. Aptdo 644. 48080 Bilbao. Spain.

The [M(C₆H₆N₃S₂)₂] compounds, where M= Cu(II), Ni(II), crystallize in the P2₁/c monoclinic space group, with a= 7.541(1), b= 7.243(1), c= 16.179(5) Å, [[beta]]= 102.71(2)deg., Z= 2, R= 0.024, wR= 0.043, for the copper(II) compound, and a= 7.476(1), b= 7.298(1), c= 15.862(5) Å, [[beta]]=101.13(2)deg., Z= 2, R= 0.032, wR= 0.049, for the nickel(II) complex. The structure of both compounds consists of discrete monomeric molecules with four coordinate square planar copper(II) and nickel(II) ions (see Figure). The metal ion is joined to two thiophene-2-carbaldehyde thiosemicarbazone ligand by the azomethinic nitrogen and the sulphur atom of the thioamide group.

IR, reflectance and EPR spectra together with the antitumoral activity will be discussed.