All-electron relativistic calculations have been performed on the low-lying electronic states of InCl by using the internally contracted multireference singles and doubles configuration interaction with the Davidson correction method. The potential energy curves and the spectroscopic constants are obtained. The C 1Π1 state has also been studied by using other internally contracted multireference methods, and it is found that the spectroscopic constants can be well reproduced by the multireference average quadratic coupled cluster method. Moreover, the essentials that affect the spectroscopic properties of the C 1Π1 state are discussed. Besides the X 1Σ+, Π0−3, A 3Π0+, B 3Π1, Π23, and C 1Π1 states, some valence excited states with shallow minima close to each other and four Rydberg states are also obtained. With the aid of the theoretical results, some experimental weak bands are reanalyzed: it is proved that the so-called “D state” is not a single state in fact, but a set of closely spaced states with shallow potential wells, and the symmetry of the E state is predicted to be Π0+3.

systems are observed and analyzed, and the spectroscopic constants of the C 1 P state are obtained. The results indicates there are some new bound electronic states lying at about 37 705 cm À1 . Theoretical calculations have also been performed on the electronic states of InBr by using coupled-cluster single-and double-linear response theory (CCSD-LRT). The theoretical results agree with our experimental analyses very well.

All-electron relativistic calculations on the ground and valence excited states of the GaCl molecule have been performed using extended internally contracted multireference electron correlation techniques. The potential energy curves (PECs) of all the 12 Λ–S states and the 23 Ω states generated from them are plotted, and the spectroscopic constants (SCs) of bound states are fitted. This seems to be the first time that a study has been made of the spin–orbit coupling effects of valence states and the transition properties of A 3Π0+, B 3Π1 and C 1Π1 states of the GaCl molecule in a theoretical way. On comparison of the calculated results obtained from different multireference electron correlation methods, we find that the size-extensivity corrections improve the theoretical Te, re and ωe results significantly, and the multireference average quadratic coupled cluster method well reproduces the experimental values in most cases. The PEC shape and the SCs of the C 1Π1 state are affected by both the avoided crossing rule among Ω states of the same symmetry and the size-extensivity correction. The C 1Π1 state has a very shallow potential well . The lifetime of the C 1Π1 state is of the order of a nanosecond, while that of the A 3Π0+ and B 3Π1 states is of the order of a microsecond.

Ab initio calculations on the ground and valence excited states of the GaBr molecule have been performed by using the entirely uncontracted all-electronic aug-cc-pVQZ basis sets and the internally contracted multireference singles and doubles configuration interaction method with Davidson size-extensivity correction and Douglas-Kroll scalar relativistic correction. The potential energy curves of all valence states and the spectroscopic constants of bound states are fitted. It is the first time that the entire 23 Ω states generated from the 12 Λ−S states of the GaBr molecule are studied in a theoretical way. Calculation results well reproduce most of the experimental data. The effects of the spin−orbit coupling and the avoided crossing rule between Ω states of the same symmetry are analyzed. The observed diffuse absorption bands near 36000 cm-1 can be contributed to the transitions from the C1(II) and other higher shallow potential well excited states, lying at the region of about 34000−38000 cm-1, to the ground state. The transition properties of the A3Π0 + and B3Π1 states to the ground-state transitions are predicted for the first time, including the transition dipole moments, the Franck−Condon factors and the radiative lifetimes. The lifetime of the A3Π0 + state of the GaBr molecule is of the order of milliseconds, while that of the B3Π1 state is of the order of microseconds.

Ab initio calculations on the ground and valence excited states of the GaF molecule have been performed by using the internally contracted multireference electronic correlation methods (MR-CISD, MR-CISD + Q, and MR-AQCC) with entirely uncontracted all-electronic basis sets and Douglas-Kroll scalar relativistic correction. The potential energy curves of all valence states and the spectroscopic constants of bound states are fitted. It is the first time that the 12 valence Lambda-S states of GaF molecule and all of the 23 Omega states generated from the former are studied in a theoretical way. Calculation results well reproduce most of the experimental data. The effects of the size-extensivity correction and the avoided crossing rule between Omega states of the same symmetry are analyzed. The transition properties of the A 3Pi0+, B 3Pi1, C 1Pi1, and 3Sigma1+ states are predicted, including the transition dipole moments, the Franck-Condon factors and the radiative lifetimes. The radiative lifetime of the C 1Pi1 state of GaF molecule is of the order of nanosecond, implying that it is a rather short-live state. The lifetimes of the B 3Pi1 and 3Sigma1+ states are of the order of microsecond, while the lifetime of the A 3Pi0+ state are the order of millisecond.