Hyperfine Interactions and Metal Atom Dynamics in a Number of Stannyl Phosphide Compounds and the Detailed Crystal Structure of Triphenyltin Chloride Revisited

Temperature-dependent 119Sn Mossbauer effect (ME) spectroscopy has been used to elucidate the hyperfine parameters (isomer shift and quadrupole splitting) as well as the dynamics of the motion of tin in three triphenyltin phosphide complexes, namely P(SnPh3)3 (C54H45PSn3, 1), P7(SnPh3)3 (C54H45P7Sn3, 2), and [Na(benzo-15-crown-5)][P(SnPh3)2] (C50H50NaO5PSn2, 3), as well as in triphenyltin chloride (4). Although the isomer shifts are very similar for all four compounds, the quadrupole splitting is dependent upon their detailed structures. The metal atom vibrations are essentially isotropic with respect to the principal symmetry axis passing through the tin atom and the triphenyltin moiety. The crystal structure of triphenyltin chloride has been re-determined at four different temperatures, and the root-mean-square amplitudes-of-vibration of the metal atom have been evaluated from the crystallographic Ui,j values and compared with the corresponding data derived from the Mossbauer measurements. These metal atom dynamics have been compared with those of the stannyl phosphide complexes derived from ME data and related to their structural details. The sensitivity of the ME technique with respect to elucidating the metal atom dynamics is demonstrated in detail.