Affiliation:
1. Institute of Theoretical Chemistry Ulm University 89069 Ulm Germany
2. Institute of Inorganic Chemistry I Materials and Catalysis Ulm University 89069 Ulm Germany
3. Helmholtz Institute Ulm (HIU) Electrochemical Energy Storage 89069 Ulm Germany
Abstract
AbstractBased on quantum chemical calculations, we predict strong solvatochromism in a light‐driven molecular photocatalyst for hydrogen generation, that is we show that the electronic and optical properties of the photocatalyst strongly depend on the solvent it is dissolved in. Our calculations in particular indicate a solvent‐dependent relocation of the highest occupied molecular orbital (HOMO). Ground‐state density functional theory and linear response time‐dependent density functional theory calculations were applied in order to investigate the influence of implicit solvents on the structural, electronic and optical properties of a molecular photocatalyst. Only at high dielectric constants of the solvent, is the HOMO located at the metal center of the photosensitizer, whereas at low dielectric constants the HOMO is centered at the metal atom of the catalytically active complex. We elucidate the electronic origins of this strong solvatochromic effect and sketch the consequences of these insights for the use of photocatalysts in different environments.
Funder
Deutsche Forschungsgemeinschaft
Studienstiftung des Deutschen Volkes
Ministerium für Wissenschaft, Forschung und Kunst Baden-Württemberg
Subject
General Chemistry,Catalysis,Organic Chemistry