摘要：

The reactions of solutions of TlPF 6 and OPPh 3 in tetrahydrofuran or acetone with NBu 4 [AuR 2 ] (R=C 6 Cl 5 , C 6 F 5 ) gave the new complexes [Au(C 6 Cl 5 ) 2 ] 2 [Tl(OPPh 3 )][Tl(OPPh 3 )(L)] (L=THF ( 1 ), acetone ( 2 )) and the previously reported [Tl(OPPh 3 ) 2 ][Au(C 6 F 5 ) 2 ] ( 3 ). The crystal structures of complexes 1 and 2 display extended unsupported chains with short intermolecular interactions between alternating gold( I ) and thallium( I ) centres. Moreover, the Tl I centres show two different types of geometrical environments, such as pseudotetrahedral and distorted trigonal-bipyramidal, due to the presence of solvent molecules that act as ligands in the solid-state structure. Quasirelativistic and nonrelativistic ab initio calculations were performed to study the nature of the intermetallic Au I –Tl I interactions and are consistent with the presence of a high ionic contribution (80%) and dispersion-type (van der Waals) interaction with a charge-transfer contribution (20%) when relativistic effects are taken into account. All complexes are luminescent in the solid state at room temperature and at 77 K. Complexes 1 and 2 show site-selective excitation, probably due to the different environments around the Tl I centres. The DFT and time-dependent (TD)-DFT calculations are in agreement with the experimental excitation spectra for all complexes and confirm the site-selective excitation behaviour as a function of the Tl I geometrical environment.

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