%0 Journal Article %1 Sieger.2003 %A Sieger, Monika %A Wanner, Matthias %A Kaim, Wolfgang %A Stufkens, Derk J. %A Snoeck, Theo L. %A Zalis, Stanislav. %D 2003 %J Inorganic Chemistry %K DFT;EPR DFT;charge Raman TDDFT;cobalt acceptor azabutadiene cobalt complex excited ligand pi radical state state;IR transfer transition %N 10 %P 3340--3346 %R 10.1021/ic026078t %T Low-Valent Cobalt Complexes with Three Different p Acceptor Ligands: Experimental and DFT Studies of the Reduced and the Low-Lying Excited States of (R-DAB)Co(NO)(CO), R-DAB = Substituted 1,4-Diaza-1,4-butadiene %V 42 %X The complexes (RN=CH-CH=NR)Co(NO)(CO) with R = iso-Pr, 2,6-diisopropylphenyl, or p-tolyl are chem. and electrochem. reducible to radical anions at potentials which strongly depend on R. The DFT calcd. structure for the neutral compd. with R = iPr agrees with the expt., and the computed structure of the anion radical reveals changes according to a redn. of the R-DAB ligand. EPR results confirm an (R-DAB)-based singly occupied MO in [(RNCHCHNR)Co(NO)(CO)].bul.-, with minor but detectable contributions from NO as supported by IR spectroelectrochem. and as quantified by DFT spin d. calcns. The calcns. indicate increasingly stabilized CO, NO, and RNCHCHNR p* acceptor orbitals, in that order. On the basis of TD-DFT (time-dependent d. functional theory) calcns., the lowest-lying excited states are assigned to metal-to-(R-DAB) charge transfer transitions while bands due to the metal-to-nitrosyl charge transfer occur at higher energies but still in the visible region. Resonance Raman studies were used to probe these assignments. [on SciFinder(R)]

@article{Sieger.2003, abstract = {The complexes (RN=CH-CH=NR)Co(NO)(CO) with R = iso-Pr, 2,6-diisopropylphenyl, or p-tolyl are chem. and electrochem. reducible to radical anions at potentials which strongly depend on R. The DFT calcd. structure for the neutral compd. with R = iPr agrees with the expt., and the computed structure of the anion radical reveals changes according to a redn. of the R-DAB ligand. EPR results confirm an (R-DAB)-based singly occupied MO in [(RNCHCHNR)Co(NO)(CO)].bul.-, with minor but detectable contributions from NO as supported by IR spectroelectrochem. and as quantified by DFT spin d. calcns. The calcns. indicate increasingly stabilized CO, NO, and RNCHCHNR \textgreek{p}* acceptor orbitals, in that order. On the basis of TD-DFT (time-dependent d. functional theory) calcns., the lowest-lying excited states are assigned to metal-to-(R-DAB) charge transfer transitions while bands due to the metal-to-nitrosyl charge transfer occur at higher energies but still in the visible region. Resonance Raman studies were used to probe these assignments. [on SciFinder(R)]}, added-at = {2022-06-15T11:26:56.000+0200}, author = {Sieger, Monika and Wanner, Matthias and Kaim, Wolfgang and Stufkens, Derk J. and Snoeck, Theo L. and Zalis, Stanislav.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/239cfb859c4705b3ff2be0d6246c4d03d/huebleriac}, doi = {10.1021/ic026078t}, interhash = {be8482b82a6e0936a72f9a51c164e8f1}, intrahash = {39cfb859c4705b3ff2be0d6246c4d03d}, issn = {0020-1669}, journal = {Inorganic Chemistry}, keywords = {DFT;EPR DFT;charge Raman TDDFT;cobalt acceptor azabutadiene cobalt complex excited ligand pi radical state state;IR transfer transition}, number = 10, pages = {3340--3346}, timestamp = {2022-06-15T09:26:56.000+0200}, title = {Low-Valent Cobalt Complexes with Three Different \textgreek{p} Acceptor Ligands: Experimental and DFT Studies of the Reduced and the Low-Lying Excited States of (R-DAB)Co(NO)(CO), R-DAB = Substituted 1,4-Diaza-1,4-butadiene}, volume = 42, year = 2003 }