本文采用完全活性空间自洽场(complete active space self-consistent field,CASSCF)和加戴维森校正的多参考组态相互作用(multireference configuration interaction with Davidson correction,MRCI+Q)方法,研究了超氧阴离子(O_(2)^(-)...本文采用完全活性空间自洽场(complete active space self-consistent field,CASSCF)和加戴维森校正的多参考组态相互作用(multireference configuration interaction with Davidson correction,MRCI+Q)方法,研究了超氧阴离子(O_(2)^(-))的低激发电子态及自旋-轨道耦合(spin-orbit coupling,SOC)效应对电子态的影响.使用aug-cc-pV5Z-dk基组,计算了O_(2)^(-)第一和第二解离极限对应的42个Λ-S态的势能曲线(potential energy curves,PECs)以及束缚态的光谱常数.同时考虑SOC效应,计算了这42个Λ-S态分裂形成的84个Ω态的PECs和部分束缚态的光谱常数.其中第一解离极限结果与已有文献高度一致,第二解离极限结果为本文计算提供.这些结果为研究O_(2)^(-)的电子结构和光谱性质提供了重要的理论依据.针对a^(4)Σ_(4)^(-)态的双势阱现象,本文通过比较不同基组下的计算结果,证实了a^(4)Σ_(4)^(-)态的双势阱形成源于与a^(4)Σ_(4)^(-)态的避免交叉影响.此外,研究发现基组大小直接影响a^(4)Σ_(4)^(-)态的首个势阱深度,这进一步表明基组选择对光谱常数计算的精确性至关重要.本文数据集可在科学数据银行https://doi.org/10.57760/sciencedb.j00213.00076中访问获取.展开更多
The potential energy curves （PECs） of 14 A-S states for magnesium chloride （MgC1） have been calculated by using multi-reference configuration interaction method with Davidson correction （MRCI ＋ Q）. The core-val...The potential energy curves （PECs） of 14 A-S states for magnesium chloride （MgC1） have been calculated by using multi-reference configuration interaction method with Davidson correction （MRCI ＋ Q）. The core-valence correlation （CV）, scalar relativistic effect, and spin-orbit coupling （SOC） effect are considered in the electronic structure computations. The spectroscopic constants of X2∑＋ and A2П states have been obtained, which are in good agreement with the existing theoretical and experimental results. Furthermore, other higher electronic states are also characterized. The permanent dipole moments （PDMs） of A-S states and the spinorbit （SO） matrix elements between A-S states are also computed. The results indicate that the abrupt changes of PDMs and the SO matrix elements are attributed to the avoided crossing between the states with the same symmetry. The SOC effect is taken into account with Breit-Panli operator, which makes the 14 A-S states split into 30 Ωstates, and leads to a double-well potential of the Ω =（3）1/2 state. The energy splitting for the A2I-I is calculated to be 53.61 cm-1 and in good agreement with the experimental result 54.47 cm-1. The transition dipole moments （TDMs）, Franck-Condon factors （FCFs）, and the corresponding radiative lifetimes of the selected transitions from excited Ω states to the ground state X2∑＋ 1/2 have been reported. The computed radiative lifetimes tV1, of low-lying excitesΩ states are all on the order of 10 ns. Finally, the feasibility of laser cooling of MgC1 molecule has been analyzed.展开更多
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 high level quantum chemistry ab inito multi-reference configuration interaction （MRCI） method with large V5Z basis set is used to calculate the spectroscopic properties of the 15 A-S electronic states （X1∑＋, ...The high level quantum chemistry ab inito multi-reference configuration interaction （MRCI） method with large V5Z basis set is used to calculate the spectroscopic properties of the 15 A-S electronic states （X1∑＋, A I П, 1 △, 1 ∑, 3∑＋, 3П, 3△, 3△ , 5∑＋, 5П, 5△, 1П （II）, ofAsO＋ radical correlated to the dissociation limit As＋（3pg） ＋ O（3pg） and As＋（IDg） ＋ O（1Dg）. In order to obtain better potential curves and more accurate spectroscopic properties, the Davidson modification is taken into account. With the potential energy curves （PECs） determined here, vibrational levels G（v） and inertial rotation constants Bu are computed for all the bound electronic states when the rotational quantum number J equals zero （J = 0）. Except for the states X1∑＋, A1П , it is the first time that the multi-reference configuration calculation has been used on the 13 A-S electronic states of the AsO＋ radical. The potential energy curves of all the A-S electronic states are depicted according to the avoided crossing rule of the same symmetry. Spin-orbit coupling effect （SOC） is introduced into the states X1 ∑＋, A1 П, 3П to consider its effects on the spectroscopic properties. Transition dipole moments （TDMs） from A1П 1, 3 П1 states to the ground state X1∑0＋ are predicted as well.展开更多
利用量子化学从头计算方法MRCI+Q在AVQZ级别上对BS+离子进行了研究.通过计算得到了与BS+离解极限B+(1Sg)+S(3Pg)和B+(1Sg)+S(1D)对应的5个Λ-S态,确认了BS+离子的基态为X3Π电子态,而第一激发态1Σ+的激发能T e仅仅为564.53 cm 1.首次...利用量子化学从头计算方法MRCI+Q在AVQZ级别上对BS+离子进行了研究.通过计算得到了与BS+离解极限B+(1Sg)+S(3Pg)和B+(1Sg)+S(1D)对应的5个Λ-S态,确认了BS+离子的基态为X3Π电子态,而第一激发态1Σ+的激发能T e仅仅为564.53 cm 1.首次纳入的旋轨耦合效应(SOC)使得BS+的5个Λ-S态分裂成为9个态,原有的两个离解极限分裂为B+(1S0)+S(3P2),B+(1S0)+S(3P1),B+(1S0)+(3P1)以及B+(1S0)+S(1D2).在考虑自旋轨道耦合效应之后,态的基态为X2态.通过势能曲线(PECs)可以发现所得到的Λ-S态和态均为束缚态,利用LEVEL8.0程序拟合得到了对应电子态的光谱常数,这些结果可以为实验和理论方面进一步研究BS+的光谱性质提供准确的电子结构信息.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
文摘本文采用完全活性空间自洽场(complete active space self-consistent field,CASSCF)和加戴维森校正的多参考组态相互作用(multireference configuration interaction with Davidson correction,MRCI+Q)方法,研究了超氧阴离子(O_(2)^(-))的低激发电子态及自旋-轨道耦合(spin-orbit coupling,SOC)效应对电子态的影响.使用aug-cc-pV5Z-dk基组,计算了O_(2)^(-)第一和第二解离极限对应的42个Λ-S态的势能曲线(potential energy curves,PECs)以及束缚态的光谱常数.同时考虑SOC效应,计算了这42个Λ-S态分裂形成的84个Ω态的PECs和部分束缚态的光谱常数.其中第一解离极限结果与已有文献高度一致,第二解离极限结果为本文计算提供.这些结果为研究O_(2)^(-)的电子结构和光谱性质提供了重要的理论依据.针对a^(4)Σ_(4)^(-)态的双势阱现象,本文通过比较不同基组下的计算结果,证实了a^(4)Σ_(4)^(-)态的双势阱形成源于与a^(4)Σ_(4)^(-)态的避免交叉影响.此外,研究发现基组大小直接影响a^(4)Σ_(4)^(-)态的首个势阱深度,这进一步表明基组选择对光谱常数计算的精确性至关重要.本文数据集可在科学数据银行https://doi.org/10.57760/sciencedb.j00213.00076中访问获取.
基金Project supported by the National Natural Science Foundation of China(Grand Nos.11564019,11147158,11264020,and 11574114)Jiangxi Provincial Education Department Project,China(Grand No.GJJ170654)
文摘The potential energy curves （PECs） of 14 A-S states for magnesium chloride （MgC1） have been calculated by using multi-reference configuration interaction method with Davidson correction （MRCI ＋ Q）. The core-valence correlation （CV）, scalar relativistic effect, and spin-orbit coupling （SOC） effect are considered in the electronic structure computations. The spectroscopic constants of X2∑＋ and A2П states have been obtained, which are in good agreement with the existing theoretical and experimental results. Furthermore, other higher electronic states are also characterized. The permanent dipole moments （PDMs） of A-S states and the spinorbit （SO） matrix elements between A-S states are also computed. The results indicate that the abrupt changes of PDMs and the SO matrix elements are attributed to the avoided crossing between the states with the same symmetry. The SOC effect is taken into account with Breit-Panli operator, which makes the 14 A-S states split into 30 Ωstates, and leads to a double-well potential of the Ω =（3）1/2 state. The energy splitting for the A2I-I is calculated to be 53.61 cm-1 and in good agreement with the experimental result 54.47 cm-1. The transition dipole moments （TDMs）, Franck-Condon factors （FCFs）, and the corresponding radiative lifetimes of the selected transitions from excited Ω states to the ground state X2∑＋ 1/2 have been reported. The computed radiative lifetimes tV1, of low-lying excitesΩ states are all on the order of 10 ns. Finally, the feasibility of laser cooling of MgC1 molecule has been analyzed.
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 Nos.11274097 and 61275132)the Natural Science Foundation of Henan Province,China(Grant No.2008A140008)
文摘The high level quantum chemistry ab inito multi-reference configuration interaction （MRCI） method with large V5Z basis set is used to calculate the spectroscopic properties of the 15 A-S electronic states （X1∑＋, A I П, 1 △, 1 ∑, 3∑＋, 3П, 3△, 3△ , 5∑＋, 5П, 5△, 1П （II）, ofAsO＋ radical correlated to the dissociation limit As＋（3pg） ＋ O（3pg） and As＋（IDg） ＋ O（1Dg）. In order to obtain better potential curves and more accurate spectroscopic properties, the Davidson modification is taken into account. With the potential energy curves （PECs） determined here, vibrational levels G（v） and inertial rotation constants Bu are computed for all the bound electronic states when the rotational quantum number J equals zero （J = 0）. Except for the states X1∑＋, A1П , it is the first time that the multi-reference configuration calculation has been used on the 13 A-S electronic states of the AsO＋ radical. The potential energy curves of all the A-S electronic states are depicted according to the avoided crossing rule of the same symmetry. Spin-orbit coupling effect （SOC） is introduced into the states X1 ∑＋, A1 П, 3П to consider its effects on the spectroscopic properties. Transition dipole moments （TDMs） from A1П 1, 3 П1 states to the ground state X1∑0＋ are predicted as well.
文摘利用量子化学从头计算方法MRCI+Q在AVQZ级别上对BS+离子进行了研究.通过计算得到了与BS+离解极限B+(1Sg)+S(3Pg)和B+(1Sg)+S(1D)对应的5个Λ-S态,确认了BS+离子的基态为X3Π电子态,而第一激发态1Σ+的激发能T e仅仅为564.53 cm 1.首次纳入的旋轨耦合效应(SOC)使得BS+的5个Λ-S态分裂成为9个态,原有的两个离解极限分裂为B+(1S0)+S(3P2),B+(1S0)+S(3P1),B+(1S0)+(3P1)以及B+(1S0)+S(1D2).在考虑自旋轨道耦合效应之后,态的基态为X2态.通过势能曲线(PECs)可以发现所得到的Λ-S态和态均为束缚态,利用LEVEL8.0程序拟合得到了对应电子态的光谱常数,这些结果可以为实验和理论方面进一步研究BS+的光谱性质提供准确的电子结构信息.
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.
