p Charge and Spin Delocalization in Mixed-Valent Vinylruthenium-Triarylamine-Conjugates with Planarized Triarylamines
Breimaier S, Fröhlich N, Herberger J, Linseis M, Kivala M, Winter RF (2022)
Publication Type: Journal article
Publication year: 2022
Journal
DOI: 10.1021/acs.organomet.1c00619
Abstract
We report on three new vinylruthenium-triaryl-amine (TA) conjugates with planarized TA substituents. The neutral, mono-, and dioxidized forms of the complexes were scrutinized by UV/vis/NIR, IR, and EPR spectroscopies as well as by quantum chemical calculations. By analyzing the intervalence charge-transfer (IVCT) transitions of the mixed-valent radical cations, we obtain information on the extent of electronic coupling between the chemically different redox sites. Completely delocalized Ru-MeTA+ shows a vibrationally structured, nonsolvatochromic IVCT band. Decreased blueshifts of the indicative Ru(CO) stretching vibration during the first oxidation and larger A(N-14) EPR hyperfine splitting constants in concert with smaller g values indicate enhanced TA contributions to the singly occupied molecular orbital of the other two complexes Ru-TOTA & BULL;+ and Ru-DOTA & BULL;+ and hence less symmetrical charge and spin density distributions. This is also reflected by the solvatochromism and the asymmetric shape of the IVCT band with a smaller bandwidth at the low-energy side. Temperature-dependent UV/vis/NIR spectroscopy of mixed-valent Ru-TOTA & BULL;+ and Ru-DOTA & BULL;+ revealed that the band skewing is due to the vibrational coupling of the IVCT transition to symmetrical vibrations, placing these radical cations near or at the class II/III borderline according to Robin and Day.
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Germany (DE)How to cite
APA:
Breimaier, S., Fröhlich, N., Herberger, J., Linseis, M., Kivala, M., & Winter, R.F. (2022). p Charge and Spin Delocalization in Mixed-Valent Vinylruthenium-Triarylamine-Conjugates with Planarized Triarylamines. Organometallics. https://dx.doi.org/10.1021/acs.organomet.1c00619
MLA:
Breimaier, Stefanie, et al. "p Charge and Spin Delocalization in Mixed-Valent Vinylruthenium-Triarylamine-Conjugates with Planarized Triarylamines." Organometallics (2022).
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