Nuclear spin-spin coupling between directly bound tin atoms studied by a novel form of INDOR spectroscopy

Heteronuclear magnetic double-resonance experiments have been used to determine the signs and magnitudes of 1J(119Sn119Sn) and other coupling constants in Li[Sn(SnMe3)3]sup(.)3thf, [Fe(eta-C5H5)[P(OPh3)]2 [Sn(SnMe3)3]], and SnMe2(SnMe3)2. Values of ca. -5000 Hz are found in the first of these compounds, and the results indicate that in general tin-tin coupling constants are determined mainly by changes in βsub(SnSn), the s-overlap integral for the Sn-Sn bond, brought about by changes in the substituents at the tin atoms. A new double-resonance method for recording the spectra of species in low abundance is also described. (author)