%0 Journal Article %1 publ9344953 %A Gillery, Claire %A Rosmus, Pavel %A Werner, Hans Joachim %A Stoll, Hermann %A Maier, John P. %D 2004 %J Mol. Phys. %K chemie imported werner from:alexanderdenzel theoretische stuttgart theochem %N 21-22 %P 2227–2236 %R 10.1080/00268970410001734314 %T A theoretical study of the electronically excited states in linear and cyclic C₆⁺ %U http://dx.doi.org/10.1080/00268970410001734314 %V 102 %X The electronically excited doublet and quartet states of the linear (D ∞h ) and cyclic (C 2V ) C 6 + ion were studied using high-level ab initio methods. For the linear ion it is found that the three lowest excited 2 π g states, which contribute to the n 2 π g -X 2 π u transitions between 1.88 and 2.73 eV, are strongly coupled and form avoided crossings if the bond distances are varied. This leads to a centrosymmetric double minimum potential of the 2 2 π g state. For the cyclic C 2v structures the lowest states have 2 A 1 and 2 B 2 symmetries. At their equilibrium geometries both states are almost degenerate and their energies are 0.3 eV lower than the minimum of the linear X 2 π u state. The excitation energies are strongly affected by geometry relaxation effects. The adiabatic excitation energies of the cyclic 2 2 A 1 and the linear 1 2 π g states are predicted to be about 1.9 eV, i.e. close to the observed band origin. Several electronically excited states-2 2 A 2 , 2 2 B 1 , 2 2 B 2 -of the cyclic structure and the 2 2 π g state of the linear structure were calculated between 2.3 and 2.5eV, i.e. higher than the observed band origin at 2.17eV. Due to strong electronic and vibronic couplings a reliable prediction of relative intensities is presently not possible, and therefore the calculated transition moments cannot be used for the interpretation of the experimental spectrum.

@article{publ9344953, abstract = {The electronically excited doublet and quartet states of the linear (D ∞h ) and cyclic (C 2V ) C 6 + ion were studied using high-level ab initio methods. For the linear ion it is found that the three lowest excited 2 π g states, which contribute to the n 2 π g -X 2 π u transitions between 1.88 and 2.73 eV, are strongly coupled and form avoided crossings if the bond distances are varied. This leads to a centrosymmetric double minimum potential of the 2 2 π g state. For the cyclic C 2v structures the lowest states have 2 A 1 and 2 B 2 symmetries. At their equilibrium geometries both states are almost degenerate and their energies are 0.3 eV lower than the minimum of the linear X 2 π u state. The excitation energies are strongly affected by geometry relaxation effects. The adiabatic excitation energies of the cyclic 2 2 A 1 and the linear 1 2 π g states are predicted to be about 1.9 eV, i.e. close to the observed band origin. Several electronically excited states-2 2 A 2 , 2 2 B 1 , 2 2 B 2 -of the cyclic structure and the 2 2 π g state of the linear structure were calculated between 2.3 and 2.5eV, i.e. higher than the observed band origin at 2.17eV. Due to strong electronic and vibronic couplings a reliable prediction of relative intensities is presently not possible, and therefore the calculated transition moments cannot be used for the interpretation of the experimental spectrum.}, added-at = {2019-03-01T15:49:43.000+0100}, author = {Gillery, Claire and Rosmus, Pavel and Werner, Hans Joachim and Stoll, Hermann and Maier, John P.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2b70363f8bf6d17f64000bc03aa6d4e13/theochem}, doi = {10.1080/00268970410001734314}, interhash = {aac1e48a39e33be16aba570678e36c74}, intrahash = {b70363f8bf6d17f64000bc03aa6d4e13}, issn = {00268976}, journal = {Mol. Phys.}, keywords = {chemie imported werner from:alexanderdenzel theoretische stuttgart theochem}, number = {21-22}, pages = {2227–2236}, timestamp = {2019-03-01T14:49:43.000+0100}, title = {{A theoretical study of the electronically excited states in linear and cyclic C₆⁺}}, url = {http://dx.doi.org/10.1080/00268970410001734314}, volume = 102, year = 2004 }