SYNTHESIS AND X-RAY STRUCTURE OF A NEW TC(IV) OXALATO COMPLEX - K4[(C2O4)2TC(MU-O)2TC(C2O4)2].3H2O

The synthesis and characterization of the complex K4[(C2O4)2Tc(mu-O)2Tc(C2O4)2].3H2O by IR, UV-Vis spectroscopy is described; X-ray crystal structure determination is also reported. The complex is dimeric and contains a Tc(mu-O)2Tc unit in which a strong Tc-Tc interaction is present. Crystals are triclinic, space group P1BAR, a = 8.765(2), b = 9.895(2), c = 12.822(4) angstrom, alpha = 87.47(1)degrees, beta = 88.41(1), gamma = 71.03(2)degrees, Z = 2, V = 1050.4. Each technetium atom is bound to two oxalato anions resulting in an octahedral coordination. From IR data it was possible to assign the frequencies of the ring system vibrations as well for other polyamino-polycarboxylato complexes.