Ab initio study on luminescent properties and aurophilic attraction of [Au-2(dpm)(i-mnt)] and its related Au(I) complexes (dpm = bis(disphosphino-methane and i-mnt = i-malonitriledithiolate)

作者：Pan QJ; Zhang HX^*

来源：Organometallics, 2004, 23(22): 5198-5209.

DOI：10.1021/om0498652

The ground- and excited-state properties of the model compound [Au-2(dpm)(i-mnt)] (1) (dpm = bis(diphosphino)methane and i-mnt = i-malononitriledithiolate) are studied by ab initio methods. The calculated Au-Au distance (2.913 Angstrom) and the corresponding Au-Au stretching frequency (110 cm(-1)) in the (1)A' ground state at the MP2 level indicate the existence of weak aurophilic attraction in the compound. Four excited states of 1 producing the emissions in the gas phase are obtained by CIS calculations. The IPCM model and the dimerization model, [Au-2(dpm)(i-mnt)](2) (1(...)1), are employed to account for the solvent and solid effects, respectively. The 454 nm emission from the b(3)A"-->(1)A' transition is assigned as an Au-Au-->S charge transfer ((MMLCT)-M-3) transition, and the interaction between the sigma/pi-(Au-2) and pi(i-mnt) orbitals rationalizes the much longer Au-Au distance (3.467 Angstrom) in the b(3)A" excited state. The c(3)A' excited state gives the 307 nm emission in the gas phase and the 512 nm emission in acetonitrile, both with the character of the Au-Au-->i-mnt charge transfer, where the latter is comparable to experimental 558 nm emission of [Au-2(dmpm)(i-mnt)] (dmpm = bis(dimethylphosphino)methane) in acetonitrile. The calculated absorptions of 1 in acetonitrile agree well with experimental observations. The comparison between 1 and related Au(I) complexes ([Au-2(dpm)(2)](2+) (2), [Au-2(PH3)(2)(i-mnt)] (3), and [Au-2(dpm)(SCH2S)] (4)) contributes to the understanding of the luminescence and aurophilicity of these Au(I) complexes.

• 出版日期2004-10-25
• 单位吉林大学