Assigning Optical Absorption Transitions with Light-Induced Crystal Structures: Case Study of a Single-Crystal Nanooptomechanical Transducer

UV/vis absorption spectroscopy affords indirect structural information about the photochemistry and photophysics of molecules by inferring types of electronic transitions from spectral features. Direct structural information would become available, though, if light-induced crystal structures could be mapped against changes in optical absorption spectra as a photochemical process evolves. We present a series of light-induced crystal structures that track real-time changes in solid-state optical absorption spectra of a crystalline nanooptomechanical transducer, while the transduction process unfolds within its crystal lattice at 100 K. Results afford a combined structural and spectral mapping of its solid-state optical absorption, from which the operational mechanism of nanooptomechanical transduction is revealed. Metal-to-ligand and metal-centered charge-transfer bands are assigned to optical absorption peaks directly from their three-dimensional (3D) light-induced crystal structures. This approach could be used to characterize many solid-state optoelectronic materials.

Automated summary

UV/vis absorption spectroscopy provides indirect structural information about the photochemistry and photophysics of molecules by inferring types of electronic transitions from spectral features. Direct structural information could be obtained by mapping light-induced crystal structures against changes in optical absorption spectra. This study reveals the operational mechanism of nanooptomechanical transduction through a combined structural and spectral mapping of solid-state optical absorption.