Modeling dark- and light-induced crystal structures and single-crystal optical absorption spectra of ruthenium-based complexes that undergo SO₂-linkage photoisomerization

Journal Article · 19 December 2021 · Journal of Chemical Physics

DOI: https://doi.org/10.1063/5.0077415 · OSTI ID:1901712

Jain, Apoorv ^[1]; Cole, Jacqueline M.  ^[2]; Vázquez-Mayagoitia, Álvaro ^[3]; Sternberg, Michael G. ^[3]

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1. Univ. of Cambridge (United Kingdom)
2. Univ. of Cambridge (United Kingdom); Rutherford Appleton Laboratory (United Kingdom); Argonne National Lab. (ANL), Argonne, IL (United States)
3. Argonne National Lab. (ANL), Lemont, IL (United States)

A family of coordination complexes of the type [Ru(SO₂)(NH₃)₄X]^m+Y_n– (m, n = 1 or 2) exhibit optical switching capabilities in their single-crystal states. This striking effect is caused by the light-induced formation of SO₂-linkage photoisomers, which are metastable if kept at suitably cool temperatures. We modeled the dark- and light-induced states of these large crystalline complexes via plane-wave (PW)- and molecular-orbital (MO)-based density functional theory (DFT) and time-dependent DFT in order to calculate their structural and optical properties; the calculated results are compared with experimental data. We show that the PW-DFT-based periodic models replicate the structural properties of these complexes more effectively than the MO-DFT-based molecular-fragment models, observing only small deviations in key bond lengths relative to the experimentally derived crystal structures. The periodic models were also found to more effectively simulate trends seen in experimental optical absorption spectra, with optical absorbance and coverage of the visible region increasing with the formation of the photoinduced geometries. The contribution of the metastable photoisomeric species more heavily focuses on the lower-energy end of the spectra. Spectra generated from the molecular-fragment models are limited by the geometry of the fragment used and the number of excited-state roots considered in those calculations. In general, periodic models outperform the molecular-fragment models owing to their ability to better appreciate the periodic phenomena that are present in these crystalline materials as opposed to MO approaches, which are finite methods. We thus demonstrate that PW-DFT-based periodic models should be considered as a more than viable method for simulating the optical and electronic properties of these single-crystal optical switches.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: Science and Technologies Facilities Council (STFC-UK); USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1901712
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 23 Vol. 155; ISSN 0021-9606
• Publisher: American Institute of Physics (AIP)Copyright Statement
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
coordination complex
crystal structure
dark states
density functional theory
energy minimization
optical absorption spectroscopy
optoelectronics
photo-isomerization