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Dynamic Stark-induced degenerate state (DSIDS) is essential to generate electronic coherent angular momentum to identify molecular chirality. We previously derived DSIDS for phenylalanine enantiomers in the independent interaction model (IIM), in which two linearly polarized nonresonant UV lasers independently interact with relevant two electronic excited states. We present a numerical method to derive DSIDS beyond IIM. Here, both lasers interact with both excited states, and laser input parameters are determined for DSIDS located at the center of the excited states. The numerical results reasonably agree with those calculated in the IIM, which elucidate the validity of DSIDS in the IIM.

A set of harmonic potential surfaces have been obtained at the CASSCF/6-311+G** level for the ground, n–p*, and p–p* states of 9Hadenine. They have been used to analyze experimental R2PI and resonance fluorescence spectra and the excited state lifetimes of adenine. A tentative plausible assignment has been proposed, which takes into account a strong coupling between these electronic states. Using the potential surfaces, the excess energy dependence of the excited state lifetimes of adenine has been interpreted, and the lifetime of the n–p * state at the band origin has also been estimated to be in the order of 10 ns.

Geometries, vibrational frequencies, excitation energies, and vibronic spectra of seven excited states of C6H5 have been studied by multireference ab initio calculations. For the 1 2 B 1 ,1 2 B 2 ,2 2 B 2 , and 2 2 B 1 states the most intense vibronic peaks are calculated at 17952, 37744, 43380, and 43251 cm −1 , respectively, and for 1 2 A 2 , 2 2 A 1 , and 3 2 A 1 upper estimates for adiabatic excitation energies are 22176, 30988, and 42543 cm −1 . We have assigned the 530–440 nm band in the absorption spectra to 1 2 B 1 with possible contribution from 1 2 A 2 , the 265–230 nm band to 1 2 B 2 and 3 2 A 1 , and intense peaks starting from ∼212 nm to 2 2 B 1 and 2 2 B 2 .

Density functional B3LYP calculations have been performed to investigate dissociation pathways of benzene trication in order to understand the mechanism of dissociative ionization of benzene after irradiation in intense laser fields. Numerous decomposition products can be formed: H 2 CCCH 2+ +C 3 H 3 + (with the activation barrier of 38.4 kcal/mol), cyclobutadiene dication C 4 H 4 2+ +C 2 H 2 + (53.0 kcal/mol), C 6 H 5 2+ +H + (64–65 kcal/mol), etc. The C 2 H 2 + detachment channels have the highest exothermicity (−131 to −138 kcal/mol), followed by C 3 H 3 + detachment (−125.7) and finally H + detachment (−83.7). The fragments are expected to be produced with high-translational energy due to high Coulomb repulsion energy barriers.

Singlet–triplet separation and heat of formation of phenylcarbene were calculated by using the B3LYP, RCCSD(T), G2M, G3, CASSCF, CASPT2 and MRCI methods. Our calculated values are 2.5±1 kcal/mol for the singlet–triplet splitting energy, 113.5±1 kcal/mol for the standard heat of formation (ΔH f 298 0 ) of singlet phenylcarbene, and 111.0±2 kcal/mol for the standard heat of formation of triplet phenylcarbene. While the singlet–triplet separation is in good agreement with previous theoretical and experimental data, the standard heat of formation of triplet phenylcarbene is about 7–8 kcal/mol higher than the experimental value (103.8±2.2 kcal/mol by Squires et al. [J. Chem. Soc., Perkin Trans. 2 (1999) 2249]).

This paper presents a comprehensive theoretical treatment of the low-lying electronic states of the molecular ion AsCl+ correlating with the lowest dissociation asymptote As+ (3P) + Cl (2P). All-electron CASSCF + CI calculations have been made with averaged atomic natural orbital basis sets. There are four bound states, namely X2Π, A2Π, 1 4 Σ − and 1 4 Π . Spectroscopic constants are calculated for the bound states and are in good agreement with experimental data for the doublet states.