title: The valence and Rydberg excited states of CH2: a theoretical exploration.
abstract: Using the completed active space second-order perturbation (CASPT2) method, valence and Rydberg excited states of CH(2) molecule are probed with the large atomic natural orbital (ANO-L) basis set. Five states are optimized and the geometric parameters are in good agreement with the available data in literatures, furthermore, the state of 2(1)B(1) is obtained for the first time. Valence and Rydberg excited states of CH(2) are also calculated for the vertical transitions with the ANO-L+ basis set that is constructed by adding a set of 1s1p1d Rydberg orbitals into the ANO-L basis set. Two Rydberg states of the p(~3)A(2) and r(~3) B(1) at 9.88 and 10.50 eV are obtained for the first time, and the 3a(1) → 3d(yz) nature of the state p(~3)A(2) and the 3a(1) → d(x2-y2) nature of the state r(~3)B(1) are confirmed.
authors: Department of Chemistry, Shanxi Normal University, Linfen 041004, China. butong.lee@gmail.com
authors: Bu-Tong
authors: BT
authors: Li
authors: Zi-Zhang
authors: ZZ
authors: Wei
authors: Hai-Shun
authors: HS
authors: Wu