Sensitivity of the photo-physical properties of organometallic complexes to small chemical changes - Condensed Matter > Strongly Correlated Electrons

Sensitivity of the photo-physical properties of organometallic complexes to small chemical changes - Condensed Matter > Strongly Correlated Electrons - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: We investigate an effective model Hamiltonian for organometallic complexesthat are widely used in optoelectronic devices. The two most importantparameters in the model are $J$, the effective exchange interaction between the$\pi$ and $\pi^*$ orbitals of the ligands, and $\epsilon^*$, the renormalizedenergy gap between the highest occupied orbitals on the metal and on theligand. We find that the degree of metal-to-ligand charge transfer MLCTcharacter of the lowest triplet state is strongly dependent on the ratio$\epsilon^*-J$. $\epsilon^*$ is purely a property of the complex and can bechanged significantly by even small variations in the complex-s chemistry, suchas replacing substituents on the ligands. We find that that small changes in$\epsilon^*-J$ can cause large changes in the properties of the complex,including the lifetime of the triplet state and the probability of injectedcharges electrons and holes forming triplet excitations. These results givesome insight into the observed large changes in the photophysical properties oforganometallic complexes caused by small changes in the ligands.

Autor: A. C. Jacko, B. J. Powell, Ross H. McKenzie

Fuente: https://arxiv.org/