The diruthenium(III) compound (m-oxa)Ru(acac)(2)(2) 1, oxa(2-) =oxamidato(2-), acac(-) =2,4-pentanedionato exhibits an S=1 ground state with antiferromagnetic spin-spin coupling (J=-40 cm(-1)). The molecular structure in the crystal of 1·2 C(7)H(8) revealed an intramolecular metal-metal distance of 5.433 \AAA and a notable asymmetry within the bridging ligand. Cyclic voltammetry and spectroelectrochemistry (EPR, UV/Vis/NIR) of the two-step reduction and of the two-step oxidation (irreversible second step) produced monocation and monoanion intermediates (K(c) =10(5.9)) with broad NIR absorption bands (e ca. 2000 M(-1)cm(-1)) and maxima at 1800 (1(-)) and 1500 nm (1(+)). TD-DFT calculations support a Ru(III)Ru(II) formulation for 1(-) with a doublet ground state. The 1(+) ion (Ru(IV)Ru(III)) was calculated with an S=3/2 ground state and the doublet state higher in energy (DE=694.6 cm(-1)). The Mulliken spin density calculations showed little participation of the ligand bridge in the spin accommodation for all paramagnetic species (m-oxa)Ru(acac)(2)(2)(n), n=+1, 0, -1, and, accordingly, the NIR absorptions were identified as metal-to-metal (intervalence) charge transfers. Whereas only one such NIR band was observed for the Ru(III)Ru(II) (4d(5)/4d(6)) system 1(-), the Ru(IV)Ru(III) (4d(4)/4d(5)) form 1(+) exhibited extended absorbance over the UV/Vis/NIR range.on SciFinder (R)
%0 Journal Article
%1 Agarwala.2012
%A Agarwala, Hemlata
%A Scherer, Thomas Michael
%A Maji, Somnath
%A Mondal, Tapan Kumar
%A Mobin, Shaikh M.
%A Fiedler, Jan
%A Urbanos, Francisco A.
%A Jimenez-Aparicio, Reyes
%A Kaim, Wolfgang
%A Lahiri, Goutam Kumar
%D 2012
%J Chemistry (Weinheim an der Bergstrasse, Germany)
%K imported
%N 18
%P 5667--5675
%T Correspondence of Ru(III) Ru(II) and Ru(IV) Ru(III) mixed valent states in a small dinuclear complex
%V 18
%X The diruthenium(III) compound (m-oxa)Ru(acac)(2)(2) 1, oxa(2-) =oxamidato(2-), acac(-) =2,4-pentanedionato exhibits an S=1 ground state with antiferromagnetic spin-spin coupling (J=-40 cm(-1)). The molecular structure in the crystal of 1·2 C(7)H(8) revealed an intramolecular metal-metal distance of 5.433 \AAA and a notable asymmetry within the bridging ligand. Cyclic voltammetry and spectroelectrochemistry (EPR, UV/Vis/NIR) of the two-step reduction and of the two-step oxidation (irreversible second step) produced monocation and monoanion intermediates (K(c) =10(5.9)) with broad NIR absorption bands (e ca. 2000 M(-1)cm(-1)) and maxima at 1800 (1(-)) and 1500 nm (1(+)). TD-DFT calculations support a Ru(III)Ru(II) formulation for 1(-) with a doublet ground state. The 1(+) ion (Ru(IV)Ru(III)) was calculated with an S=3/2 ground state and the doublet state higher in energy (DE=694.6 cm(-1)). The Mulliken spin density calculations showed little participation of the ligand bridge in the spin accommodation for all paramagnetic species (m-oxa)Ru(acac)(2)(2)(n), n=+1, 0, -1, and, accordingly, the NIR absorptions were identified as metal-to-metal (intervalence) charge transfers. Whereas only one such NIR band was observed for the Ru(III)Ru(II) (4d(5)/4d(6)) system 1(-), the Ru(IV)Ru(III) (4d(4)/4d(5)) form 1(+) exhibited extended absorbance over the UV/Vis/NIR range.on SciFinder (R)
@article{Agarwala.2012,
abstract = {The diruthenium(III) compound [(\textgreek{m}-oxa){Ru(acac)(2)}(2)] [1, oxa(2-) =oxamidato(2-), acac(-) =2,4-pentanedionato] exhibits an S=1 ground state with antiferromagnetic spin-spin coupling (J=-40 cm(-1)). The molecular structure in the crystal of 1·2 C(7)H(8) revealed an intramolecular metal-metal distance of 5.433 {\AA}A and a notable asymmetry within the bridging ligand. Cyclic voltammetry and spectroelectrochemistry (EPR, UV/Vis/NIR) of the two-step reduction and of the two-step oxidation (irreversible second step) produced monocation and monoanion intermediates (K(c) =10(5.9)) with broad NIR absorption bands (\textgreek{e} ca. 2000 M(-1)cm(-1)) and maxima at 1800 (1(-)) and 1500 nm (1(+)). TD-DFT calculations support a Ru(III)Ru(II) formulation for 1(-) with a doublet ground state. The 1(+) ion (Ru(IV)Ru(III)) was calculated with an S=3/2 ground state and the doublet state higher in energy (\textgreek{D}E=694.6 cm(-1)). The Mulliken spin density calculations showed little participation of the ligand bridge in the spin accommodation for all paramagnetic species [(\textgreek{m}-oxa){Ru(acac)(2)}(2)](n), n=+1, 0, -1, and, accordingly, the NIR absorptions were identified as metal-to-metal (intervalence) charge transfers. Whereas only one such NIR band was observed for the Ru(III)Ru(II) (4d(5)/4d(6)) system 1(-), the Ru(IV)Ru(III) (4d(4)/4d(5)) form 1(+) exhibited extended absorbance over the UV/Vis/NIR range.[on SciFinder (R)]},
added-at = {2022-06-15T11:26:56.000+0200},
author = {Agarwala, Hemlata and Scherer, Thomas Michael and Maji, Somnath and Mondal, Tapan Kumar and Mobin, Shaikh M. and Fiedler, Jan and Urbanos, Francisco A. and Jimenez-Aparicio, Reyes and Kaim, Wolfgang and Lahiri, Goutam Kumar},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2a5a73c556de3db07f6bcaf42174c57eb/huebleriac},
interhash = {e0d6af10b3f84f6f9f062b39865a8a32},
intrahash = {a5a73c556de3db07f6bcaf42174c57eb},
issn = {1521-3765},
journal = {Chemistry (Weinheim an der Bergstrasse, Germany)},
keywords = {imported},
number = 18,
pages = {5667--5675},
timestamp = {2022-06-15T09:26:56.000+0200},
title = {Correspondence of Ru(III) Ru(II) and Ru(IV) Ru(III) mixed valent states in a small dinuclear complex},
volume = 18,
year = 2012
}
