文摘
The influence of intermolecular interactions on the Mössbauer quadrupole splitting () of 119Sn was investigatedin detail by density functional theory (DFT) calculations. Six organotin(IV) complexes [Me2Sn(acac)2 (1),Ph3SnCl (2), Me3Sn-succinimide (3), Me3Sn-phthalimide (4), Me3SnCl (5), and cHex3SnCl (6)] of knownsolid-state structures and quadrupole splittings were selected. Theoretical values were calculated for bothfully optimized geometries and experimental solid-state structures of different size, and the results werecompared to the experimental values. Compared to a synthetic procedure described in the literature forcompound 4, a more convenient synthesis is reported here. The experimental of this compound has alsobeen redetermined at 80 K. For compounds with negligible intermolecular interactions in the solid state,calculated values obtained did not vary significantly. In contrast, the calculated values turned out to bevery sensitive to the size of the supramolecular moiety considered in the crystal lattice. The crystal structureof compound 2 shows no significant intermolecular interactions; however, the calculated and the experimental values remained very different, even when the supramolecular moiety considered was extended. Distortionof the coordination sphere of tin in the molecule of 2 toward a trigonal bipyramidal geometry was considered,and a possible weak intermolecular Sn···Cl interaction was included in the model. Steps of the distortionfollowed the new structure correlation function, which was found for the R3SnCl (R = alkyl, aryl) compounds.The experimental value could be approached by this method. These results suggest that compound 2 isinvolved in some unexpected intermolecular interaction at 80 K.