83827-01-4Relevant academic research and scientific papers
Heteropolynuclear gold complexes with metallophilic interactions: Modulation of the luminescent properties
Calhorda, Maria Jose,Ceamanos, Carmen,Crespo, Olga,Gimeno, M. Concepcion,Laguna, Antonio,Larraz, Carmen,Vaz, Pedro D.,Villacampa, M. Dolores
, p. 8255 - 8269 (2010/12/18)
Metalloligands of stoichiometry [AuCl(P-N)] have been obtained by the reaction of the heterofunctional phosphines P-N = PPh2py, PPh 2CH2CH2py, or PPhpy2 with [AuCl(tht)] (tht = tetrahydrothiophene). Reactions of these metalloligands with several metal compounds have afforded heteropolynuclear species which exhibit luminescent properties. The stoichiometries depend on the molar ratio and the heterometal. Thus, the reaction with [Cu(NCMe)4]+ in a molar ratio 2:1 gives the trinuclear compounds [Au2CuCl 2(P-N)2]+, in which the structure and Au...Cu interactions depend on the phosphine ligand. With rhodium and iridium derivatives the reactivity is different leading to complexes of the type [AuMCl2(cod)(P-N)] for P-N = PPh2py, PPhpy2, and [Au2M2Cl(cod)2(P-N)2]Cl with PPh2CH2CH2py. Using [MCl2(NCPh) 2] (M = Pd, Pt) in a 2:1 molar ratio yields [Au2MCl 4(P-N)2] and in a 1:1 molar ratio [AuPdCl 3(μ3-PPhpy2)]. Several compounds have been characterized by X-ray diffraction showing in many cases short Au...M distances. The luminescence of these derivatives has been studied. The metalloligands display bands assigned to intraligand (IL) transitions. For the bimetallic (Au/M) systems the luminescence depends on the heterometal present and on the metallophilic interactions. The most important excitations in the relevant energy range were assigned essentially a MMLCT character (from Rh/Ir and Au to ligands) based on density functional theory (DFT) calculations in selected complexes. The luminescence behavior in Rh/Ir [AuMCl 2(cod)(PPh2py)] complexes was interpreted on the basis of the different nature of the half occupied orbitals in the triplet state.
