The B2Σ+ state of zinc deuteride

Conventional high-resolution photographic spectroscopy has been employed to study the B²Σ-X²Σ emission system of zinc deuteride in the region 280–370 nm. The B-X system of ZnD is reported for the first time and 17 such bands have been rotationally analyzed. Many local rotational perturbations have been found in the B state and are attributable to interactions with the A²Π state. The rotational and vibrational data for ZnH (after Stenvinkel) and ZnD are complementary and enable the RKR curve for the B state to be mapped with reasonable accuracy for almost 10 000 cm⁻¹. B-X Franck-Condon factors for ZnH and ZnD are also reported.     

Rotational Analysis of the B2Σ+-X2Σ+ Bands of 12C18O+

The emission spectrum of the B²Σ⁺-X²Σ⁺ (First Negative) system of the molecular ion ¹²C¹⁸O⁺ have been photographed at a resolution sufficient to observe the spin splitting of the lines with N > 18. Four bands, 0-1, 0-3, 1-4 and 2-5, have been rotationally analyzed and the molecular constants of the B²Σ⁺ , v = 0,1, 2 and X²Σ⁺ , v =1, 3, 4, 5 have been obtained.     

The 41Σ+ electronic state of LiCs molecule

The 4¹Σ⁺ state of LiCs molecule is observed experimentally for the first time. The inverted perturbation approach (IPA) method is used to derive the potential energy curve of the state from the measured spectra. The experiment is accompanied by theoretical calculations of adiabatic potentials for excited states in LiCs including 4¹Σ⁺, performed with the MOLPRO program package. The irregular shape of the 4¹Σ⁺ state potential predicted by theory is confirmed in the experiment.     

激波管壁AlO自由基B~2Σ~+-X~2Σ~+和C~2Π_r-X~2Σ~+带系辐射光谱的研究

爆轰驱动过程中产生的高温高压气流对铝质膜片、激波管壁产生烧蚀和冲刷作用,以致激波管壁、端盖上附有氧化铝等杂质,而高温下AlO自由基在气体分子的高速碰撞下被激发并产生强烈的辐射,从而干扰了高温气体辐射光谱的分析。用爆轰驱动加热技术将空气加热到4 000~7 000 K,利用多通道光学分析仪对AlO自由基辐射光谱进行分析,实验发现在460~530 nm波长范围内有多支辐射非常强烈的AlO自由基B2Σ+-X2Σ+(T00=20 689 cm-1)带系辐射谱带,且每支谱带都由多个带头组成,带头间隔约为2 nm,带头处于高频位置并向低频方向伸延。通过实验与理论计算相结合,重点分析了AlO自由基B2Σ+-X2Σ+带系辐射光谱的结构特征。AlO自由基C2Πr-X2Σ+(T00=33 047 cm-1)带系辐射光谱处于270~335 nm波长范围内,其辐射强度相对于B2Σ+-X2Σ+带系较弱,并且与OH基A2Σ+-X2Π(T00=32 682 cm-1)带系辐射光谱互相干扰而难以分辨,对该波段高温空气的辐射光谱分析产生不利的影响。     

N2+分子离子的B2Σu+、A2Πu和X2Σg+电子态光谱研究

采用光外差 磁旋转 速度调制吸收光谱技术 ,在可见光波段范围 16 80 0～ 175 73cm-1,对N2 + 的A2 Πu-X2 Σ+ g(12 ,6 )、(11,5 )、(7,2 )带和B2 Σ+ u -X2 Σ+ g(1,5 )带进行了测量和分析 ,推导了双原子分子振转能级在受到微扰作用时的有效哈密顿量形式 ,并分析了N2 + 的A2 Πu-B2 Σ+ u 之间存在的微扰相互作用 ,通过与实验数据的拟合得到了精确的电子态微扰常数 ξe、ηe.     

Ab initio configuration interaction study on the electronic structure of the X2Σ+, B2Σ+ and 32Σ+ states of SiO+

The energy levels and electronic structure of the X²Σ⁺, B²Σ⁺ and 3²Σ⁺ states of SiO⁺ are studied using ab initio configuration interaction (CI) calculations at and around their equilibrium internuclear distances R _e. Spectroscopic constants and the vertical excitation energy from the SiO⁺ X²Σ⁺ state are predicted for the 3²Σ⁺ state. Based on the calculated CI wavefunctions, avoided crossings of the potential energy curve for the 3²Σ⁺ state and a near-degeneracy effect in the avoided crossing region are examined. The effects of the mixing of excited configuration state functions in the total electronic wavefunctions for the 1–3 ²Σ⁺ states are investigated by analysing correlation energies in terms of the contributions from classes of excited configurations. The importance of both the near-degeneracy effect and the correlation energy effect in describing correctly the electronic structure of the 3 ²Σ⁺ state in the neighbourhood of its R _e is discussed.     

High-resolution laser excitation spectroscopy: Analysis of the B2Σ+-X2Σ+ system of CaCl

Single-mode cw dye laser excitation spectra of the (0, 0), (1, 1), and (2, 2) bands of the B²Σ⁺-X²Σ⁺ system of CaCl have been observed and assigned. Some 300 independent photo-luminescence spectra have been used in making the rotational assignment and demonstrate the power of the technique of line-by-line analysis in unraveling complex spectra. Spectroscopic constants (cm^?1) obtained from a weighted least squares fit of the data are given below. Numbers in parentheses refer to 95% confidence limits in the last digit.

     

11.

Molecule opacities of X~2Σ~+, A~2Π, and B~2Σ~+ states of CS~+          下载免费PDF全文

《中国物理 B》2019,(5)

Carbon sulfide cation(CS~+) plays a dominant role in some astrophysical atmosphere environments. In this work, the rovibrational transition lines are computed for the lowest three electronic states, in which the internally contracted multireference configuration interaction approach(MRCI) with Davison size-extensivity correction(+Q) is employed to calculate the potential curves and dipole moments, and then the vibrational energies and spectroscopic constants are extracted. The Frank–Condon factors are calculated for the bands of X~2~+Σ~+–A~2Π and X~2Σ~+–B~2Σ~+systems, and the band of X~2Σ~+–A~2Π is in good agreement with the available experimental results. Transition dipole moments and the radiative lifetimes of the low-lying three states are evaluated. The opacities of the CS~+ molecule are computed at different temperatures under the pressure of 100 atms. It is found that as temperature increases, the band systems associated with different transitions for the three states become dim because of the increased population on the vibrational states and excited electronic states at high temperature.     

12.

Zur Rotationsanalyse der2Σ →2Σ- und2II →2Σ-Banden des CO+     

R. Schmid  L. Gerö 《Zeitschrift für Physik A Hadrons and Nuclei》1933,86(5-6):297-313

     

13.

MgH分子X2Σ+,A2Π和B2Σ+电子态的势能函数   总被引：1，自引：0，他引：1       下载免费PDF全文

吕兵  周勋  令狐荣锋  杨向东  朱正和 《物理学报》2008,57(2)

利用QCISD(T),SAC-CI方法和cc-pVQZ,aug-cc-pVTZ,6-311 G及6-311 G(3df,2pd)基组,对MgH分子的基态X2Σ ,第一简并激发态A2Π和第二激发态B2Σ 的结构进行优化计算.通过对4个基组计算结果进行比较,得出6-311 G(3df,2pd)基组为最优基组.使用6-311 G(3df,2pd)基组和QCISD(T)方法对基态X2Σ ,SAC-CI方法对激发态A2Π和B2Σ 进行单点能扫描计算,然后采用Murrell-Sorbie函数及修正的Murrell-Sorbie C6函数进行拟合,得到了相应电子态的势能函数参数和对应的光谱常数.计算结果表明,用修正的Murrell-Sorbie C6函数计算得到的MgH分子基态和第一简并激发态的光谱常数ωe,ωexe,Be,αe与实验数据吻合很好.表明修正后的Murrell-Sorbie C6函数能更为准确地描述MgH分子的基态和第一激发态的势能函数.     

14.

A high-resolution study of the vacuum ultraviolet spectrum of CS: The B1Σ+-X1Σ+ system     

《Journal of Molecular Spectroscopy》1987,124(2):420-429

     

15.

Analysis of the bands of the B2Σ+-X2Σ+ transition in 12C16O+ and 13C16O+     

《Journal of Molecular Spectroscopy》1987,125(1):54-65

The First Negative bands of ¹²C¹⁶O⁺ and ¹³C¹⁶O⁺, in the spectral region 40 000–46 000 cm⁻¹, have been photographed at a resolution sufficient to resolve the spin-doubled components. These data for ¹²C¹⁶O⁺, along with previously reported data of the same transitions, as well as microwave transitions of ¹²C¹⁶O⁺ in the ground state, have been explicitly included in a least-squares fit to determine the most precise set of molecular constants to date for the B²Σ⁺ and X²Σ⁺ states of ¹²C¹⁶O⁺. Furthermore, we report a rotational analysis of the First Negative bands of ¹³C¹⁶O⁺ for the first time. Several molecular constants characterizing ¹³C¹⁶O⁺ in the B²Σ⁺ and the X²Σ⁺ states, including spin-doubling parameters, have been determined.     

16.

Rotational Analysis of the 1–4 Band of the B 2Σ+–X 2Σ+ System of 14C16O+     

W. Szajna  M. Zachwieja  R. Kępa 《光谱学快报》2013,46(3):207-212

ABSTRACT

High-resolution emission spectrum of the 1–4 band of the B ²Σ⁺–X ²Σ⁺ transition of ¹⁴C¹⁶O⁺ was observed for the first time by conventional emission spectroscopy. The band spectrum was excited in a water-cooled Geissler lamp filled with commercial gaseous carbon monoxide enriched in about 80% of the radiocarbon ¹⁴C. A rotational analysis has been carried out and obtained molecular constants have been merged with previously published data for the B ²Σ⁺–A ²Π_i and A ²Π_i–X ²Σ⁺ transitions. The principal equilibrium constants for the ground X ²Σ⁺ state obtained from this work are ω_e = 2121.7726(98), ω_e x _e = 13.9055(27), B _e = 1.815290(30), α_e = 1.6594(33) × 10^?2, and γ_e = ? 0.377(73) × 10^?4 cm^?1. Also, presently known experimental equilibrium molecular constants of the X ²Σ⁺ states of the CO⁺ isotopic molecules are summarized and isotopic dependence of the B _e and ω _e constants is discussed.     

17.

Reinvestigation of the vacuum ultraviolet spectrum of CO and isotopic species: The B1Σ+ ↔ X1Σ+ transition     

《Journal of Molecular Spectroscopy》1987,121(2):309-336

     

18.

Jet-cooled laser-induced fluorescence spectroscopy of B2Σ+–X2Σ+ system of scandium monoxide: Improved molecular constants at equilibrium     

Sheo Mukund  Suresh Yarlagadda  Soumen Bhattacharyya  S.G. Nakhate 《Journal of Quantitative Spectroscopy & Radiative Transfer》2012,113(16):2004-2008

The investigation on B²Σ⁺–X²Σ⁺ system of ScO was extended to higher vibrational levels by laser-induced fluorescence (LIF) spectroscopy in a free-jet. We have observed rotationally resolved excitation spectra for (4,0), (3,0), (2,0), and (1,2) bands in addition to the previously observed (0,0) and (1,0) bands. The wavenumbers of these bands were fitted to a Hamiltonian matrix to determine the molecular constants for the vibrational levels up to ν′=4 of the B²Σ⁺ state and ν″=2 of the X²Σ⁺ state. In addition, the vibration constants of the ground states were determined from the dispersed fluorescence wavenumbers between B²Σ⁺ (ν′=0–4) and X²Σ⁺ (ν″=0–8) transitions. The equilibrium molecular constants, derived from the extensive set of molecular constants for individual vibrational levels, were used to construct RKR potential energy curves for both the electronic states. The Franck–Condon factors were also calculated for the B²Σ⁺–X²Σ⁺ transition.     

19.

The ion-molecule reaction O+ (4S) + N2(X1Σ+) → NO+ (X1Σ +, v′) + N(4S) and the predissociation of the A2Σ+ and B2Π states of N2O+     

G. CHAMBAUD  H. GRITLI  P. ROSMUS  H.-J. WERNER  P. J. KNOWLES 《Molecular physics》2013,111(21):1793-1802

The potential energy surfaces (PESs) for several electronic states involved in the reaction O⁺ (⁴S) + N₂(X¹Σ⁺) → NO⁺ (X¹Σ ⁺, v′) + N(⁴S) and the role of the ionic N₂O⁺ intermediate have been investigated by ab initio calculations. The ⁴A″ PES, which correlates with the ground state educts, has a barrier of about 1 eV, and therefore at low collision energies the reaction cannot take place adiabatically on this surface. However, the spin-orbit coupling in the entrance channel allows the system to pass into the Renner-Teller system of the X² Π electronic ground state of the N₂O⁺ intermediate. The reaction then proceeds on these surfaces up to the region in the exit channel where a similar coupling allows it to reach the product quartet asymptote. At collision energies higher than about 1 eV, the reaction proceeds mainly on the adiabatic PES of the ⁴A″ state. The A²Σ⁺ state of N₂O⁺ predissociates via a vibronic coupling with the B²Π state, and in bent structures via a spin-orbit coupling with the ⁴A″ component of the ⁴II state. The electronic structure of the B²Π state is found to be of crucial importance for the understanding of the reactive processes in low lying electronic states of N₂O⁺.     

20.

BH 分子 Χ1Σ+ 和 B1Σ+ 态的理论研究     

李伟  朱遵略  杜丙阁  孙金锋  蔡利霞 《原子与分子物理学报》2009,26(2):224-228

本文应用 Gaussian03 程序包中提供的完全活性空间自洽场 (CASSCF) 方法, 采用标准基组 6-311++G(3d,2p) 对 BH 分子Χ1Σ+ 和 B1Σ+ 态势能曲线进行了单点能计算. 在此基础上, 利用相关理论将计算结果拟合到 Murrell-Sorbie 函数得到了与各电子态相对应的光谱常数和力常数, 并将计算结果与实验和其他理论结果进行了比较. 同时, 我们还利用光谱常数与力常数以及 Murrell-Sorbie 函数之间的关系计算了与实验光谱数据相对应的力常数和 Murrell-Sorbie 函数, 并与 CASSCF 结果进行了比较得出了一些有价值的结论. 最后, 对于具有双极小值的B1Σ+ 态给出了更精确的定量的信息.     

	$\text{X}{}^2\text{Σ}{}^{\mathrm{+}}$	$\text{B}{}^2\text{Σ}{}^{\mathrm{+}}$
$\text{T}{}_{\mathrm{e}}$	0	16856.69(2)
$\text{ω}{}_{\mathrm{e}}$	369.8(10)	366.8(10)
$\text{ω}{}_{\mathrm{e}}\text{x}{}_{\mathrm{e}}$	1.13(20)	1.28(20)
$\text{B}{}_{\mathrm{e}}$	0.15200(54)	0.15448(54)
$\text{α}{}_{\mathrm{e}}$	0.00063(34)	0.00073(35)
$\text{D}{}_{\mathrm{e}}$	1.027(16) × 10?7	1.097(17) × 10?7
$\text{γ}{}_{\mathrm{e}}$ (spin-rotation)	+0.003	?0.0630(16)

Molecule opacities of X~2Σ~+, A~2Π, and B~2Σ~+ states of CS~+

Carbon sulfide cation(CS~+) plays a dominant role in some astrophysical atmosphere environments. In this work, the rovibrational transition lines are computed for the lowest three electronic states, in which the internally contracted multireference configuration interaction approach(MRCI) with Davison size-extensivity correction(+Q) is employed to calculate the potential curves and dipole moments, and then the vibrational energies and spectroscopic constants are extracted. The Frank–Condon factors are calculated for the bands of X~2~+Σ~+–A~2Π and X~2Σ~+–B~2Σ~+systems, and the band of X~2Σ~+–A~2Π is in good agreement with the available experimental results. Transition dipole moments and the radiative lifetimes of the low-lying three states are evaluated. The opacities of the CS~+ molecule are computed at different temperatures under the pressure of 100 atms. It is found that as temperature increases, the band systems associated with different transitions for the three states become dim because of the increased population on the vibrational states and excited electronic states at high temperature.     

MgH分子X2Σ+,A2Π和B2Σ+电子态的势能函数

利用QCISD(T),SAC-CI方法和cc-pVQZ,aug-cc-pVTZ,6-311 G及6-311 G(3df,2pd)基组,对MgH分子的基态X2Σ ,第一简并激发态A2Π和第二激发态B2Σ 的结构进行优化计算.通过对4个基组计算结果进行比较,得出6-311 G(3df,2pd)基组为最优基组.使用6-311 G(3df,2pd)基组和QCISD(T)方法对基态X2Σ ,SAC-CI方法对激发态A2Π和B2Σ 进行单点能扫描计算,然后采用Murrell-Sorbie函数及修正的Murrell-Sorbie C6函数进行拟合,得到了相应电子态的势能函数参数和对应的光谱常数.计算结果表明,用修正的Murrell-Sorbie C6函数计算得到的MgH分子基态和第一简并激发态的光谱常数ωe,ωexe,Be,αe与实验数据吻合很好.表明修正后的Murrell-Sorbie C6函数能更为准确地描述MgH分子的基态和第一激发态的势能函数.     

Analysis of the bands of the B2Σ+-X2Σ+ transition in 12C16O+ and 13C16O+

The First Negative bands of ¹²C¹⁶O⁺ and ¹³C¹⁶O⁺, in the spectral region 40 000–46 000 cm⁻¹, have been photographed at a resolution sufficient to resolve the spin-doubled components. These data for ¹²C¹⁶O⁺, along with previously reported data of the same transitions, as well as microwave transitions of ¹²C¹⁶O⁺ in the ground state, have been explicitly included in a least-squares fit to determine the most precise set of molecular constants to date for the B²Σ⁺ and X²Σ⁺ states of ¹²C¹⁶O⁺. Furthermore, we report a rotational analysis of the First Negative bands of ¹³C¹⁶O⁺ for the first time. Several molecular constants characterizing ¹³C¹⁶O⁺ in the B²Σ⁺ and the X²Σ⁺ states, including spin-doubling parameters, have been determined.     

Rotational Analysis of the 1–4 Band of the B 2Σ+–X 2Σ+ System of 14C16O+

ABSTRACT

High-resolution emission spectrum of the 1–4 band of the B ²Σ⁺–X ²Σ⁺ transition of ¹⁴C¹⁶O⁺ was observed for the first time by conventional emission spectroscopy. The band spectrum was excited in a water-cooled Geissler lamp filled with commercial gaseous carbon monoxide enriched in about 80% of the radiocarbon ¹⁴C. A rotational analysis has been carried out and obtained molecular constants have been merged with previously published data for the B ²Σ⁺–A ²Π_i and A ²Π_i–X ²Σ⁺ transitions. The principal equilibrium constants for the ground X ²Σ⁺ state obtained from this work are ω_e = 2121.7726(98), ω_e x _e = 13.9055(27), B _e = 1.815290(30), α_e = 1.6594(33) × 10^?2, and γ_e = ? 0.377(73) × 10^?4 cm^?1. Also, presently known experimental equilibrium molecular constants of the X ²Σ⁺ states of the CO⁺ isotopic molecules are summarized and isotopic dependence of the B _e and ω _e constants is discussed.     

Jet-cooled laser-induced fluorescence spectroscopy of B2Σ+–X2Σ+ system of scandium monoxide: Improved molecular constants at equilibrium

The investigation on B²Σ⁺–X²Σ⁺ system of ScO was extended to higher vibrational levels by laser-induced fluorescence (LIF) spectroscopy in a free-jet. We have observed rotationally resolved excitation spectra for (4,0), (3,0), (2,0), and (1,2) bands in addition to the previously observed (0,0) and (1,0) bands. The wavenumbers of these bands were fitted to a Hamiltonian matrix to determine the molecular constants for the vibrational levels up to ν′=4 of the B²Σ⁺ state and ν″=2 of the X²Σ⁺ state. In addition, the vibration constants of the ground states were determined from the dispersed fluorescence wavenumbers between B²Σ⁺ (ν′=0–4) and X²Σ⁺ (ν″=0–8) transitions. The equilibrium molecular constants, derived from the extensive set of molecular constants for individual vibrational levels, were used to construct RKR potential energy curves for both the electronic states. The Franck–Condon factors were also calculated for the B²Σ⁺–X²Σ⁺ transition.     

The ion-molecule reaction O+ (4S) + N2(X1Σ+) → NO+ (X1Σ +, v′) + N(4S) and the predissociation of the A2Σ+ and B2Π states of N2O+

The potential energy surfaces (PESs) for several electronic states involved in the reaction O⁺ (⁴S) + N₂(X¹Σ⁺) → NO⁺ (X¹Σ ⁺, v′) + N(⁴S) and the role of the ionic N₂O⁺ intermediate have been investigated by ab initio calculations. The ⁴A″ PES, which correlates with the ground state educts, has a barrier of about 1 eV, and therefore at low collision energies the reaction cannot take place adiabatically on this surface. However, the spin-orbit coupling in the entrance channel allows the system to pass into the Renner-Teller system of the X² Π electronic ground state of the N₂O⁺ intermediate. The reaction then proceeds on these surfaces up to the region in the exit channel where a similar coupling allows it to reach the product quartet asymptote. At collision energies higher than about 1 eV, the reaction proceeds mainly on the adiabatic PES of the ⁴A″ state. The A²Σ⁺ state of N₂O⁺ predissociates via a vibronic coupling with the B²Π state, and in bent structures via a spin-orbit coupling with the ⁴A″ component of the ⁴II state. The electronic structure of the B²Π state is found to be of crucial importance for the understanding of the reactive processes in low lying electronic states of N₂O⁺.     

BH 分子 Χ1Σ+ 和 B1Σ+ 态的理论研究

本文应用 Gaussian03 程序包中提供的完全活性空间自洽场 (CASSCF) 方法, 采用标准基组 6-311++G(3d,2p) 对 BH 分子Χ1Σ+ 和 B1Σ+ 态势能曲线进行了单点能计算. 在此基础上, 利用相关理论将计算结果拟合到 Murrell-Sorbie 函数得到了与各电子态相对应的光谱常数和力常数, 并将计算结果与实验和其他理论结果进行了比较. 同时, 我们还利用光谱常数与力常数以及 Murrell-Sorbie 函数之间的关系计算了与实验光谱数据相对应的力常数和 Murrell-Sorbie 函数, 并与 CASSCF 结果进行了比较得出了一些有价值的结论. 最后, 对于具有双极小值的B1Σ+ 态给出了更精确的定量的信息.