| Abstract: | Structural and spectroscopic properties of and theoretical investigations on dinuclear Pd2(CN)4(P–P)2] (P–P=bis(dicyclohexylphosphanyl)methane ( 1 ), bis(dimethylphosphanyl)methane ( 2 )) and mononuclear trans‐Pd(CN)2(PCy3)2] ( 3 ) complexes are described. Xray structural analyses reveal Pd???Pd distances of 3.0432(7) and 3.307(4) Å in 1 and 2 , respectively. The absorption bands at λ>270 nm in 1 and 2 have 4d →5pσ electronic‐transition character. Calculations at the CIS level indicate that the two low‐lying dipole‐allowed electronic transition bands in model complex Pd2(CN)4(μ‐H2PCH2PH2)2] at 303 and 289 nm are due to combinations of many orbital transitions. The calculated interaction‐energy curve for the skewed dimer {trans‐Pd(CN)2(PH3)2]}2] is attractive at the MP2 level and implies the existence of a weak PdII–PdII interaction. |
