ELECTRONIC ABSORPTION AND MCD SPECTRA FOR PD(AUPPH(3))(8)(2+), PT(AUPPH(3))(8)(2+), AND RELATED PLATINUM-CENTERED GOLD CLUSTER COMPLEXES

摘要

Electronic absorption and 7.0 T magnetic circular dichroism (MCD) spectra in the UV-vis region, 1.6 to similar to 4.0 mu m(-1) (1 mu m-1 = 10(4) cm(-1)) are reported for [Pd(AuPPh(3))(8)](NO3)(2) and [Pt(AuPPh(3))(8)](NO3)(2) in acetonitrile solutions at room temperature. The MCD spectra are better resolved than the absorption spectra and consist of both A and B terms. The spectra are interpreted in terms of D-4d Skeletal geometry and MO's that are approximated by 5s and 6s orbitals for Pd and Pt/Au atoms, respectively. The lowest energy excited configurations and states are attributed to intraframework (IF) AU(8)(2+) transitions. Evidence is also presented for Pt 5d --> Au 6s transitions in the MCD spectra for Pt(AUPPh(3))(8)(2+). Acetonitrile solution. absorption and MCD spectra for the related Pt-centered cluster complexes [Pt(CO)(AuPPh(3))(8)](NO3)(2), [Pt(AUP(p-tolyl)(3))(8)](NO3)(2), [Pt(CUCl)(AUPPh(3))(8)](NO3)(2),[Pt(AgNO3)(AUPPh(3))(8)](NO3)(2), [Pt(Hg)(2)(AUPPh(3))(8)](NO3)(2), [Pt(HgCl)(2)(AUPPh(3))(8)](BF4)(2), and [Pt(HgNO3)(2)(AuPPh(3))(8)](BF4)(2) are also reported and interpreted within the context of the model developed for the M(AUPPh(3))(8)(2+) complexes. [References: 27]