In-depth exploration of the photophysics of a trinuclear palladium complex

Abstract

A detailed theoretical and spectroscopic study on the electronically excited states of a trinuclear palladium complex is presented both in the gas phase and solution. The application of DFT and TDDFT methods as well as a variety of spectroscopic methods to the chosen complex [Pd3{Si(mt(Me))3}2] (1, mt(Me) = methimazole) leads to the first detailed analysis of the photophysics of a symmetric trinuclear complex. In combination with the calculations, energies, structures and lifetimes of the excited electronic states (with an (3)A1 state as the lowest one) are characterized by applying the resonant-2-photon-ionization method in a molecular beam experiment as well as luminescence, time-correlated single photon counting and excited state femtosecond absorption spectroscopy in solution. These investigations are of fundamental interest to analyze photophysical properties of metal containing complexes on a molecular level.

Differential Many‐Body Cooperativity in Electronic Spectra of Oligonuclear Transition‐Metal Complexes

“…[11] In our present computations, we replacet he three Pd ions by one, two and three Pt ions, respectively,t hereby keeping the geometries of theses ubstituted complexes either fixed at the equilibrium structure of the complex [Pt 3 {Si(mt Me ) 3 } 2 ], or optimizing the geometries individually for each complex. [11] In our present computations, we replacet he three Pd ions by one, two and three Pt ions, respectively,t hereby keeping the geometries of theses ubstituted complexes either fixed at the equilibrium structure of the complex [Pt 3 {Si(mt Me ) 3 } 2 ], or optimizing the geometries individually for each complex.…”

Excited-State Dynamics of Catalytically Active Transition Metal Complexes Studied by Transient Photofragmentation in Gas Phase and Transient Absorption in Solution

“…In DMSO after photoexcitation at 330 nm the observed absorption changes are dominated by an instantaneous bleach in the region of electronic ground state absorption and a concomitant fast (*400 fs) build-up of spectrally broad and long-lived (ns time-scale) excited state absorption at 370-750 nm, which is assigned to the lowest triplet state ( 3 A 1 ). No hints on ligand dissociation or other structural/electronic changes have been observed in solution [4].…”

Low Valent Palladium Clusters: Synthesis, Structures and Catalytic Applications

“…Soon afterward, spectroscopic investigations and computational studies explored by this team uncovered the electronically excited states of the Pd 3 cluster in detail. [ 33 ] Analogous to the similar platinum cluster, this reaction is thought to start with an oxidative addition to Pd(0) initially, then the adduct reacts with excess Pd(0) complexed to release H 2 and achieve the final cluster. Before this, only Osakada and co‐workers have investigated silylene bridged palladium cluster [Pd{Pd(dmpe)} 3 ( μ 3 ‐SiPh 2 ) 3 ] (dmpe = 1,2‐bis(dimethylphosphino)ethane), [ 34 ] and recently, inspired by the development of silicon chemistry, more and more palladium clusters with silicon ligands appear like [Pd 4 {Si( i Pr) 2 } 3 (CN t Bu) 4 ], which is reported by Sunada and co‐workers.…”