Lead oxide（Pb O）, which plays the key roles in a range of research fields, has received a great deal of attention. Owing to the large density of electronic states and heavy atom Pb including in Pb O, the excited sta...Lead oxide（Pb O）, which plays the key roles in a range of research fields, has received a great deal of attention. Owing to the large density of electronic states and heavy atom Pb including in Pb O, the excited states of the molecule have not been well studied. In this work, high level multireference configuration interaction calculations on the low-lying states of Pb O have been carried out by utilizing the relativistic effective core potential. The effects of the core-valence correlation correction, the Davidson modification, and the spin–orbital coupling on the electronic structure of the Pb O molecule are estimated. The potential energy curves of 18 Λ-S states correlated to the lowest dissociation limit（Pb（~3P_g） ＋ O（~3P_g）） are reported. The calculated spectroscopic parameters of the electronic states below 30000 cm^（-1）, for instance, X^1Σ~＋, 1~3Σ~＋,and 1~3Σ^-, and their spin–orbit coupling interaction, are compared with the experimental results, and good agreements are derived. The dipole moments of the 18 Λ-S states are computed with the configuration interaction method, and the calculated dipole moments of X^1Σ~＋and 1~3Σ~＋are consistent with the previous experimental results. The transition dipole moments from 1~1Π, 2~1Π, and 2~Σ to X^1Σ~＋and other singlet excited states are estimated. The radiative lifetime of several low-lying vibrational levels of 1~1Π, 2~1Π, and 2~1Σ~＋ states are evaluated.展开更多
The electronic states of the smallest boron cluster B_(3)with excitation energies up to 5 e V are systematically investigated.Geometries and spectroscopic constants for the low-lying electronic states were calculated ...The electronic states of the smallest boron cluster B_(3)with excitation energies up to 5 e V are systematically investigated.Geometries and spectroscopic constants for the low-lying electronic states were calculated using the multireference configuration interaction method with Davidson correction(MRCI+Q).The nondegenerate 1^(2)B_(2)and 2^(2)A_(1)states are arising from the degenerate~2E~′state in D_(3h)symmetry,this is also the case for 2^(2)B_(2)and 3~2A_(1).Furthermore,vertical excitation energies,oscillator strengths,main configurations,and transitions of the excited state of B_(3)were determined.Notably,the theoretically predicted wavelengths for the X^(2)A_(1)→2^(2)A_(1)and X^(2)A_(1)→2^(2)B_(2)electronic transitions(728 nm and 457 nm,respectively)exhibit excellent agreements with experimental absorption bands observed at 736 nm and 458 nm.These theoretical findings provide critical insights into the electronic structure and geometric configuration of the B_(3)cluster.展开更多
The calculations on the potential energy curves and spectroscopic constants of the ground and low-lying excited states of BrCl^+, one of the important molecular ions in environment science, have been performed by usin...The calculations on the potential energy curves and spectroscopic constants of the ground and low-lying excited states of BrCl^+, one of the important molecular ions in environment science, have been performed by using the multireference configuration interaction method at high level of theory in quantum chemistry. Through analyses of the effects of the spin-orbit coupling interaction on the electronic structures and spectroscopic properties, the multiconflguration characteristic of the X^2Π ground state and low-lying excited states was established. The spin-orbit coupling splitting energy of the X^2 Π ground state was calculated to be 1814 cm^(-1), close to the experimental value 2070 cm^(-1). The spin-orbit coupling splitting energy of the ~2Π(II) exited state was predicted to be 766 cm^(-1). The transition dipole moments and Frank-Condon factors of the 3/2(III)-X3/2 and 1/2(III)-1/2(I) transitions were estimated, and the radiative lifetimes of the two transitions were briefly discussed.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11404180 and 11574114)the Natural Science Foundation of Heilongjiang Province,China(Grant No.A2015010)+1 种基金the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province,China(Grant No.UNPYSCT-2015095)the Natural Science Foundation of Jilin Province,China(Grant No.20150101003JC)
文摘Lead oxide（Pb O）, which plays the key roles in a range of research fields, has received a great deal of attention. Owing to the large density of electronic states and heavy atom Pb including in Pb O, the excited states of the molecule have not been well studied. In this work, high level multireference configuration interaction calculations on the low-lying states of Pb O have been carried out by utilizing the relativistic effective core potential. The effects of the core-valence correlation correction, the Davidson modification, and the spin–orbital coupling on the electronic structure of the Pb O molecule are estimated. The potential energy curves of 18 Λ-S states correlated to the lowest dissociation limit（Pb（~3P_g） ＋ O（~3P_g）） are reported. The calculated spectroscopic parameters of the electronic states below 30000 cm^（-1）, for instance, X^1Σ~＋, 1~3Σ~＋,and 1~3Σ^-, and their spin–orbit coupling interaction, are compared with the experimental results, and good agreements are derived. The dipole moments of the 18 Λ-S states are computed with the configuration interaction method, and the calculated dipole moments of X^1Σ~＋and 1~3Σ~＋are consistent with the previous experimental results. The transition dipole moments from 1~1Π, 2~1Π, and 2~Σ to X^1Σ~＋and other singlet excited states are estimated. The radiative lifetime of several low-lying vibrational levels of 1~1Π, 2~1Π, and 2~1Σ~＋ states are evaluated.
基金Project supported by the National Natural Science Foundation of China(Grant No.12274178)。
文摘The electronic states of the smallest boron cluster B_(3)with excitation energies up to 5 e V are systematically investigated.Geometries and spectroscopic constants for the low-lying electronic states were calculated using the multireference configuration interaction method with Davidson correction(MRCI+Q).The nondegenerate 1^(2)B_(2)and 2^(2)A_(1)states are arising from the degenerate~2E~′state in D_(3h)symmetry,this is also the case for 2^(2)B_(2)and 3~2A_(1).Furthermore,vertical excitation energies,oscillator strengths,main configurations,and transitions of the excited state of B_(3)were determined.Notably,the theoretically predicted wavelengths for the X^(2)A_(1)→2^(2)A_(1)and X^(2)A_(1)→2^(2)B_(2)electronic transitions(728 nm and 457 nm,respectively)exhibit excellent agreements with experimental absorption bands observed at 736 nm and 458 nm.These theoretical findings provide critical insights into the electronic structure and geometric configuration of the B_(3)cluster.
基金the National Basic Research Program of China(Grant No.2006CB601102)the National Natural Science Foundations of China(Grant Nos.20490210 and 20503001)
文摘The calculations on the potential energy curves and spectroscopic constants of the ground and low-lying excited states of BrCl^+, one of the important molecular ions in environment science, have been performed by using the multireference configuration interaction method at high level of theory in quantum chemistry. Through analyses of the effects of the spin-orbit coupling interaction on the electronic structures and spectroscopic properties, the multiconflguration characteristic of the X^2Π ground state and low-lying excited states was established. The spin-orbit coupling splitting energy of the X^2 Π ground state was calculated to be 1814 cm^(-1), close to the experimental value 2070 cm^(-1). The spin-orbit coupling splitting energy of the ~2Π(II) exited state was predicted to be 766 cm^(-1). The transition dipole moments and Frank-Condon factors of the 3/2(III)-X3/2 and 1/2(III)-1/2(I) transitions were estimated, and the radiative lifetimes of the two transitions were briefly discussed.
