A SN-119 MOSSBAUER STUDY OF HEPTACOORDINATED TIN COMPLEXES WITH MULTIDENTATE LIGANDS

Three novel heptacoordinated tin complexes with multidentate ligands w ere prepared and studied by Mossbauer spectroscopy. The complexes were identified as [MeSnCl(Hdaptsc)]Cl MeOH, [MeSnCl(H(2)dapsc)]Cl-2 2H(2) O and [ClSnCl(Hdaptsc)]Cl, where H(2)daptse = 2,6-diacetylpyridinebis (thiosemicarbazone) and H(2)dapse = 2,6-diacetylpyridinebis (semicarba zone). The structures of the first two complexes were determined by X- ray crystallography. The ligand H(2)dapse originated a fourth complex, which was characterised as [(Me(2)SnCl(2))(2)(H(2)dapsc)] in which th e two Sn atoms are probably hexacoordinated, as suggested by Mossbauer data. The isomer shifts and the quadrupole splittings of the complexe s are consistent with the structural interpretation, and correlate wel l with other literature examples and with X-ray data whenever availabl e. The correlation between Mossbauer results and structural informatio n is important considering the paucity of published data for heptacoor dinated species.