Franck--Condon factors and r-Centroids for the A 1∑+u-X1∑+g Band System of 107,109Ag2: Comparison of the Observed and Calculated Absorption Band Strengths

Franck-Condon factors and r-centrolds for the, A^1 ∑^＋ u-X^1∑^＋ 9 band system of ^107,109Ag2 are computed using Morse and Rydberg-Klein-Rees potentials for both lower and upper electronic states. The differences between the two sets of results are typically in the third decimal place for transitions involving vibrational levels with ν＇ and ν＂ up to about 15. Somewhat larger deviations appear for higher vibrational levels, but both sets of results follow the same pattern, which is to match well with the relative absorption band strength distribution in our experimental spectrum. The relative absorption band strengths are calculated by assuming that the electronic transition moment has only a weak dependence on the internuclear distance r. Good agreement between our measured and calculated absorption band strength ratios is found, which provides an excellent test of the calculated Franck- Condon factors and relative absorption band strengths. The r-centrold value for the （ν＇ = 0, ν＂ = 0） band is found to be approximately equal to the average value of r＇ and r＇＇e , indicating that the potentials of both states are not significantly aaharmonic around their minimum regions.     

利用Townsend放电测定N2(A3∑u+)亚稳态分子的扩散系数和猝灭速率常数

在纯N₂气体中,利用Townsend放电方法,对N₂(A³∑_u⁺)亚稳态分子的扩散系数D_m和猝灭速率常数K_q的测定进行了研究。分别得到:D_m=128cm²/s,K_q=8.1×10^-19cm³/s。 关键词：     

Study of hot bands in the B2Σ+u-X2Σ+g system of C-2 anion

Optical heterodyne magnetic rotation enhanced velocity modulation spectroscopy was employed to observe the visible absorption spectra of the B^2Σ^+_u-X^2Σ^+_g electronic transition of C^-_2. Four hot bands (0,1), (1,2), (2,3) and (3,4) have been observed and the band (3,4) is measured directly for the first time, so far as we know, by absorption. A rotational analysis was carried out to obtain molecular constants. With the Franck－Condon principle and the vibrational Boltzmann distribution, we have estimated the vibrational temperature of C^-_2 to be about 3000K.     

N2O+离子A2Σ+电子态的光解动力学研究

用一束波长为360.55nm的激光，通过N2O分子的（3+1）共振多光子电离（REMPI）过程制备纯净且布居完全处于X2Π(000)态的母体离子N2O+，然后用另一束波长在275—328nm范围内的可调谐激光将制备的N2O+离子激发至预解离电子态A2Σ+.实验发现，由于解离碎片NO+所具有的一定的反冲速度，其TOF质谱峰明显比N2O+母体宽.通过分析NO+碎片TOF质谱峰形状，得到了解离产物的总平均平动能〈ET〉；通过考察〈ET〉随光解能量的变化，发现光解能量在32000cm-1附近约250cm-1的变化 关键词： N2O+离子A2Σ+态 TOF质谱峰 预解离机理     

KCl:OH-中O2-色心实验研究

通过调制吸收光谱和电子自旋共振(ESR)谱的测量得知,在被高能射线辐照前后,KCl:OH^-中氧的成分主要以O₂^-的形式存在。O₂^-在样品中的浓度随辐照时间增加而增加,直至(OH)^-完全被辐照分解。O₂^-有相当强的稳定性。其存在与产生过程对增加F₂⁺激光色心的稳定性无直接作用。本文还根据ES 关键词：     

MgF自由基A2π-X2Σ+跃迁的高分辨激光诱导荧光光谱和Franck-Condon因子

MgF自由基被认为是适用于直接激光冷却的候选分子之一. 本文利用激光诱导荧光技术研究了MgF A²π-X²Σ⁺电子跃迁系统的转动分辨光谱. 在超声射流膨胀条件下利用两个镁针对SF₆/Ar气体混合放电产生MgF自由基. 在348∽370 nm范围内,实验记录了属于Δv=0,±1三个序的19个振动带. 通过对实验光谱的转动分析,确定了X²Σ⁺和A²π态的精确光谱常数. 利用实验结果结合和Rydberg-klein-rees方法计算了包括Franck-Condon因子(FCFs)在内的光谱常数. 实验结果和理论计算的FCFs之间存在显著差异,表明FCFs几乎不依赖于A²π态自旋-轨道耦合效应. 本文确定的势能曲线和FCFs为MgF分子激光冷却方案的理论模拟提供了必要的光谱数据.     

F2 Σ+ -X 2Σ +Band System of Cobalt Carbide

用脉冲直流放电产生Xe原子亚稳态5p56s[3/2]2和5p56s′[1/2]0.在单光子28000－42000cm-1能量范围内,结合飞行时间质谱技术获得Xe原子共振增强激发光谱.光谱分析表明,所有谱线来源于Xe原子5p56s[3/2]2和5p56s′[1/2]0两个亚稳态吸收单个光子向偶宇称np′、nf′自电离Rydberg态序列的跃迁.实验观测到许多新的自电离能级,并获得更精确和系统的能级位置和量子亏损值数据.     

Vibration-rotation and deperturbation analysis of A2Π-X2Σ+ and B2Σ+-X2Σ+ systems of the CaI molecule

Doppler-limited laser excitation spectroscopy employing narrow-band fluorescence detection was used to obtain a rotational and vibrational analysis in the (0, 0) and (1, 1) bands of the A²Π-X²Σ⁺ system and the (4, 2) (3, 1), (0, 0), (0, 1), (1, 2), (2, 3), and (3, 4) bands of the B²Σ⁺-X²Σ⁺ system of CaI. The A and B states are deperturbed to obtain spectroscopic constants and Franck-Condon factors. Deperturbation was necessary because of the small separation of the A and B states relative to the A ～ B interaction strength and the A²Π spin-orbit splitting. The main deperturbed constants (in cm^?1) are

     

9.

P-branch emission spectra of the A¹Π-X¹Σ⁺ system of IrN          下载免费PDF全文

樊群超  孙卫国  李会东  冯灏 《中国物理 B》2012,21(2):23301-023301

The P-branch emission spectra of (4,1) and (3,1) bands of the A¹Π-X¹Σ⁺ system of IrN molecule are studied using an analytical formula which is derived from elementary expression of molecular total energy by taking multiple spectral differences. It not only reproduces the known experimental transition lines, but also predicts the unknown spectral lines up to J= 80 for each band by using a group of fifteen known experimental transition lines.     

10.

Vibrational analysis of Fourier transform spectrum of the A³Π₀-X¹Σ⁺ and B³Π₁-X¹Σ⁺ transitions of indium monobromide     

Renu Singh  K. N. Uttam  M. D. Saksena  M. N. Deo 《Pramana》2009,73(5):889-899

The emission spectrum of InBr molecule has been recorded in the region 350–400 nm on BOMEM DA8 Fourier transform spectrometer at an apodized resolution of 0.06 cm⁻¹ using microwave excitation technique. About 61 violet degraded and single headed bands have been recorded and are classified into two band systems, viz. A³Π₀-X¹Σ⁺ and B³Π₁-X¹Σ⁺. A few new bands have been observed and are fitted in the vibrational schemes of the two systems. Revised vibrational constants have been determined. The vibrational assignments have been confirmed by observing isotope effect due to InBr⁸¹ in the 30 bands of the A³Π₀-X¹Σ⁺ system and 19 bands of the B³Π₁-X¹Σ⁺ system. The analysis is further supported by calculating the Franck-Condon factor for InBr⁷⁹ and InBr⁸¹ molecules. The following vibrational constants (in cm⁻¹) have been determined from the analysis:      

11.

Investigation of [πh9／2＋i13／2^—1]10^— Isomer in ^206 At^1     

Feng  Xichen  Wen  Shuxian 《近代物理研究所和兰州重离子加速器实验室年报》1999,(1):24-24

     

12.

MRCI study of spectroscopic and molecular properties of X¹Σ_g⁺ and A¹Π_u electronic states of the C₂ radical          下载免费PDF全文

张小妞  施德恒  孙金锋  朱遵略 《中国物理 B》2011,20(4):43105-043105

The potential energy curves (PECs) of X1Σ+g and A1Πu electronic states of the C2 radical have been studied using the full valence complete active space self-consistent field (CASSCF) method followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI) approach in conjunction with the aug-cc-pV6Z basis set for internuclear separations from 0.08 nm to 1.66 nm. With these PECs of the C2 radical,the spectroscopic parameters of three isotopologues ( 12C2 ,12C13C and 13C2 ) have been determined. Compared in detail with previous studies reported in the literature,excellent agreement has been found. The complete vibrational levels G(υ),inertial rotation constants B υ and centrifugal distortion constants D υ for the 12C2 ,12C13C and 13C2 isotopologues have been calculated for the first time for the X1Σ+g and A1Πu electronic states when the rotational quantum number J equals zero. The results are in excellent agreement with previous experimental data in the literature,which shows that the presented molecular constants in this paper are reliable and accurate.     

13.

Ar⁺ laser-induced fluorescence spectra of Cs₂: The E¹Σ_u⁺ and (1) ¹Π_g electronic states     

C. Amiot  C. Crépin  J. Vergès 《Journal of Molecular Spectroscopy》1984,107(1):28-47

Laser-induced fluorescence of Cs₂ molecules in the infrared (1.15–2.5 μm) and the visible (505–545 nm) regions has been observed using several excitation wavelengths from an argonion laser. Accurate molecular constants and potential energy curves for the pumped E¹Σ_u⁺ state and the first excited gerade ¹Π state are derived from more than 1300 fluorescence lines precisely measured with a high-resolution Fourier transform interferometer. The main molecular constants for the states are

	$\text{X}{}^2\text{Σ}{}^{\mathrm{+}}$	$\text{A}{}^2\text{Π}$	$\text{B}{}^2\text{Σ}{}^{\mathrm{+}}$
$\text{T}{}_{\mathrm{e}}$	0	15 624.67(5)	15 700.52(12)
$\text{ω}{}_{\mathrm{e}}$	238.7496(33)	241.19(7)	242.63(17)
$\text{ω}{}_{\mathrm{e}}\text{χ}{}_{\mathrm{e}}$	0.62789(64)	0.53(5) (Pekeris)	1.17(12) (Pekeris)
$\text{B}{}_{\mathrm{e}}$	0.0693254(84)	0.070460(14)	0.071572(22)
$\text{α}{}_{\mathrm{e}}\text{× 10}{}^4$	2.640(35)	2.15(10)	3.95(2)
$\text{A}{}_{\mathrm{e}}$	—	45.8968(52)	—
$\text{R}{}_{\mathrm{e}}\text{(}\text{A}\text{?}\text{)}$	2.8286(2)	2.8057(3)	2.7839(4)

     

14.

Lifetime vibrational interference during the NO 1s^-1π^* resonant excitation studied by the NO⁺(A ¹Π → X ¹Σ⁺) fluorescence     

A. Ehresmann  W. Kielich  L. Werner  Ph. V. Demekhin  D. V. Omel''yanenko  V. L. Sukhorukov  K.-H. Schartner  H. Schmoranzer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(2):235-246

Dispersed fluorescence from fragments formed after the de-excitation of the 1s^-1π^* resonances of N^*O and NO^* has been measured in the spectral range of 118–142 nm. This range is dominated by lines of atomic nitrogen and oxygen fragments and by the bands in the NO⁺ ion which result from the participator Auger decay of the 1s^-1π^* resonances. Ab-initio calculations of the transition probabilities between vibrational levels during the reaction NO N^*O ⇒ NO were used to explain the observed intensity dependence for the fluorescence bands on the exciting-photon energy across the resonances and on both v^′ and v^′′ vibrational quantum numbers. The multiplet structure of the 1s^-1π^* resonance and lifetime vibrational interference explain the observed exciting-photon energy dependence of the fluorescence intensity. A strong spin-orbit coupling between singlet and triplet states of NO⁺ is proposed to reduce additional cascade population of the state via radiative transitions from the and states and to explain remaining differences between measured and calculated integral fluorescence intensities.     

15.

N₂O⁺离子A²Σ⁺电子态高振动能级的转动结构分析          下载免费PDF全文

汪华  刘世林  刘杰  王凤燕  姜波  杨学明 《中国物理 B》2008,17(2):796-802

利用一束波长为36055nm的激光，通过(3+1)共振多光子电离方法制备纯净的且处于X²Π_1/2，3/2(000)态的N₂O⁺离子，用另一束激光激发所制备的离子到第一电子激发态A²Σ⁺的不同振动能级，然后解离，通过检测解离碎片NO⁺强度随光解光波长的变化，得到了转动分辨的N₂     

16.

Laser spectroscopy of CuS: Analysis of the A²Σ-X²Π_i system     

F. David  M. Douay  Y. Lefebvre 《Journal of Molecular Spectroscopy》1985,112(1):115-126

Laser excitation spectra of the A²Σ-X²Π_i system have been recorded for ⁶³CuS and ⁶⁵CuS isotopic molecules with a single-mode dye laser operating in the region 17000–18000 cm^?1. For highly overlapped sequences, use of a monochromator as a narrow band filter was necessary to allow rotational analysis. A simultaneous fit of all eight analyzed bands has led to the following spectroscopic constants for ⁶³CuS (in cm^?1):

	$\text{T}{}_{\mathrm{e}}\text{(}\text{cm}{}^{\mathrm{?1}}\text{)}$	$\text{ω}{}_{\mathrm{e}}\text{(}\text{cm}{}^{\mathrm{?1}}\text{)}$	$\text{B}{}_{\mathrm{e}}\text{(}\text{cm}{}^{\mathrm{?1}}\text{)}$	$\text{R}{}_{\mathrm{e}}\text{(}\text{A}\text{?}\text{)}$
$\text{E}{}^1\text{Σ}{}_{\mathrm{u}}{}^{\mathrm{+}}$	20195.23	29.10	0.00891	5.340733
(1) ${}^1\text{Π}{}_{\mathrm{g}}$	13913.42	18.44	0.00781	5.697722

     

17.

Influence of relaxation effects on probabilities of the 2s2p³⁵S₂－2s²2p^{2 3}P_1，2 intercombination transitions in NII          下载免费PDF全文

袁萍  刘欣生  颉录有  张义军  董晨钟 《中国物理》2003,12(3):271-274

Transition probabilities of the 2s2p^3 {}^5S_2－2s^22p^2 {}^3P_{1,2} intercombination transitions in NII have been calculated by using a large-scale multiconfiguration Dirac－Fock method. In the calculation the most important effects of relativity, correlation, and relaxation are considered. From the calculated transition probabilities, the lifetime of the 2s2p^3 {}^5S_2 metastable state is derived. The result is in excellent agreement with the latest experimental result. In the meantime the influence of anomalously strong relaxation effects on probabilities of the 2s2p^3 {}^5S_2－2s^22p^2 {}^3P_{1,2} lines in NII have been found.     

18.

Extended Measurement of the v₂ (1^- ←0⁺) Band of H₃O⁺ by Mid-Infrared Diode Laser Spectroscopy          下载免费PDF全文

郑锐  王瑞波李松黄光明  段传喜 《中国物理快报》2007,24(9):2569-2571

Twenty-five new R-branch lines of the v2（1^-← 0^＋） band of H3O^＋ are measured using diode laser velocity modulation spectroscopy between 1070 and 1230 cm^-1. The H3O^＋ ions are produced in a high voltage ac discharge with water diluted in helium. The observed lines together with all the previously published measurements are fit to the standard vibration-rotational Hamiltonian of an oblate symmetric top, yielding a set of improved molecular constants. All the sextic centrifugal distortion constants for both 0^＋ and 1^- states are determined precisely. The observed R（13, 0） transition is shifted about -0.129 cm^-1 from its calculated value, indicating that a near degeneracy exists between the （13, 0）^＋ and （13, 3）^- ground-state rotation-inversion levels.     

19.

Infrared diode laser spectroscopy of O₂–N₂O van der Waals complex in the v₁ symmetric stretch region of N₂O          下载免费PDF全文

李松  郑锐  段传喜 《中国物理 B》2014,(12):137-141

The rovibrational spectrum of O2–N2O van der Waals complex is measured in the ν1 symmetric stretch region of N2 O monomer using a tunable diode laser spectrometer. The complex is generated by a slit-pulsed supersonic expansion with gas mixtures of O2, N2 O, and He. Both a- and b-type transitions are observed. The effective Hamiltonian for an open-shell complex consisting of a diatomic molecule in a ^3Σ electronic state and a closed-shell partner is used to analyze the observed spectrum. Molecular constants in the vibrationally excited state are determined accurately. The band-origin of the spectrum is determined to be 1284.7504（25） cm^-1, red-shifted from that of the N2 O monomer by ～ 0.1529 cm^-1.     

20.

Improving luminescent property of SrIn₂ O₄ :Eu³⁺ by co-doped A⁺ （A = Li, Na, K） or Sm³⁺          下载免费PDF全文

王志军  李盼来  杨志平  郭庆林 《中国物理 B》2013,(4):495-499

A series of SrIn2 O4 :Eu3+ phosphors are synthesized by a high temperature solid-state method, and their luminescent properties are investigated. They can be excited by 395-nm radiation, and produce red emission (619 nm); however, they have a low absorption of near-ultraviolet light with the wavelength of 400nm-405 nm. When co-doped with A+ (A=Li, Na, K), the emission intensity of SrIn2O4 :Eu3+ is significantly enhanced, but its emission and excitation spectral profile is unchanged. With co-doping Sm3+ , not only is the emission intensity of SrIn2 O4 :Eu3+ enhanced, but also the absorption is broadened and strengthened in the range of 400 nm-405nm. The effect of Sm3+ -doped content on the emission intensity of SrIn2O4 :Eu3+ , Sm3+ is investigated, and the optimal Sm3+ content is 0.02 mol.     

State	$\text{v}$	$\text{T}{}_{\mathrm{v}}$	$\text{B}{}_{\mathrm{v}}$	$\text{D}{}_{\mathrm{v}}\text{× 10}{}^6$	$\text{γ}{}_{\mathrm{v}}$	$\text{p}{}_{\mathrm{v}}$	$\text{a}{}_{\mathrm{v}}\text{× 10}{}^6$
$\text{A}{}^2\text{Σ}{}^{\mathrm{?}}$	0	17924.335 (7)	0.17989 (4)	0.177 (7)	0.03853 (7)
$\text{X}{}^2\text{Π}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$	1	842.574 (7)	0.18701 (4)	0.163 (7)		0.01496 (9)
	0	432.566 (6)	0.18818 (4)	0.162 (7)		0.01508 (9)
$\text{X}{}^2\text{Π}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}$	1	411.289 (7)	0.18724 (4)	0.184 (7)			?0.96 (6)
	0	—	0.18839 (4)	0.160 (7)			?0.11 (6)

P-branch emission spectra of the A1Π-X1Σ+ system of IrN

The P-branch emission spectra of (4,1) and (3,1) bands of the A¹Π-X¹Σ⁺ system of IrN molecule are studied using an analytical formula which is derived from elementary expression of molecular total energy by taking multiple spectral differences. It not only reproduces the known experimental transition lines, but also predicts the unknown spectral lines up to J= 80 for each band by using a group of fifteen known experimental transition lines.     

Vibrational analysis of Fourier transform spectrum of the A3Π0-X1Σ+ and B3Π1-X1Σ+ transitions of indium monobromide

The emission spectrum of InBr molecule has been recorded in the region 350–400 nm on BOMEM DA8 Fourier transform spectrometer at an apodized resolution of 0.06 cm⁻¹ using microwave excitation technique. About 61 violet degraded and single headed bands have been recorded and are classified into two band systems, viz. A³Π₀-X¹Σ⁺ and B³Π₁-X¹Σ⁺. A few new bands have been observed and are fitted in the vibrational schemes of the two systems. Revised vibrational constants have been determined. The vibrational assignments have been confirmed by observing isotope effect due to InBr⁸¹ in the 30 bands of the A³Π₀-X¹Σ⁺ system and 19 bands of the B³Π₁-X¹Σ⁺ system. The analysis is further supported by calculating the Franck-Condon factor for InBr⁷⁹ and InBr⁸¹ molecules. The following vibrational constants (in cm⁻¹) have been determined from the analysis:      

MRCI study of spectroscopic and molecular properties of X1Σg+ and A1Πu electronic states of the C2 radical

The potential energy curves (PECs) of X1Σ+g and A1Πu electronic states of the C2 radical have been studied using the full valence complete active space self-consistent field (CASSCF) method followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI) approach in conjunction with the aug-cc-pV6Z basis set for internuclear separations from 0.08 nm to 1.66 nm. With these PECs of the C2 radical,the spectroscopic parameters of three isotopologues ( 12C2 ,12C13C and 13C2 ) have been determined. Compared in detail with previous studies reported in the literature,excellent agreement has been found. The complete vibrational levels G(υ),inertial rotation constants B υ and centrifugal distortion constants D υ for the 12C2 ,12C13C and 13C2 isotopologues have been calculated for the first time for the X1Σ+g and A1Πu electronic states when the rotational quantum number J equals zero. The results are in excellent agreement with previous experimental data in the literature,which shows that the presented molecular constants in this paper are reliable and accurate.     

Ar+ laser-induced fluorescence spectra of Cs2: The E1Σu+ and (1) 1Πg electronic states

Laser-induced fluorescence of Cs₂ molecules in the infrared (1.15–2.5 μm) and the visible (505–545 nm) regions has been observed using several excitation wavelengths from an argonion laser. Accurate molecular constants and potential energy curves for the pumped E¹Σ_u⁺ state and the first excited gerade ¹Π state are derived from more than 1300 fluorescence lines precisely measured with a high-resolution Fourier transform interferometer. The main molecular constants for the states are

Lifetime vibrational interference during the NO 1s-1π* resonant excitation studied by the NO+(A 1Π → X 1Σ+) fluorescence

Dispersed fluorescence from fragments formed after the de-excitation of the 1s^-1π^* resonances of N^*O and NO^* has been measured in the spectral range of 118–142 nm. This range is dominated by lines of atomic nitrogen and oxygen fragments and by the bands in the NO⁺ ion which result from the participator Auger decay of the 1s^-1π^* resonances. Ab-initio calculations of the transition probabilities between vibrational levels during the reaction NO N^*O ⇒ NO were used to explain the observed intensity dependence for the fluorescence bands on the exciting-photon energy across the resonances and on both v^′ and v^′′ vibrational quantum numbers. The multiplet structure of the 1s^-1π^* resonance and lifetime vibrational interference explain the observed exciting-photon energy dependence of the fluorescence intensity. A strong spin-orbit coupling between singlet and triplet states of NO⁺ is proposed to reduce additional cascade population of the state via radiative transitions from the and states and to explain remaining differences between measured and calculated integral fluorescence intensities.     

N2O+离子A2Σ+电子态高振动能级的转动结构分析

利用一束波长为36055nm的激光，通过(3+1)共振多光子电离方法制备纯净的且处于X²Π_1/2，3/2(000)态的N₂O⁺离子，用另一束激光激发所制备的离子到第一电子激发态A²Σ⁺的不同振动能级，然后解离，通过检测解离碎片NO⁺强度随光解光波长的变化，得到了转动分辨的N₂     

Laser spectroscopy of CuS: Analysis of the A2Σ-X2Πi system

Laser excitation spectra of the A²Σ-X²Π_i system have been recorded for ⁶³CuS and ⁶⁵CuS isotopic molecules with a single-mode dye laser operating in the region 17000–18000 cm^?1. For highly overlapped sequences, use of a monochromator as a narrow band filter was necessary to allow rotational analysis. A simultaneous fit of all eight analyzed bands has led to the following spectroscopic constants for ⁶³CuS (in cm^?1):

Influence of relaxation effects on probabilities of the 2s2p35S2－2s22p2 3P1，2 intercombination transitions in NII

Transition probabilities of the 2s2p^3 {}^5S_2－2s^22p^2 {}^3P_{1,2} intercombination transitions in NII have been calculated by using a large-scale multiconfiguration Dirac－Fock method. In the calculation the most important effects of relativity, correlation, and relaxation are considered. From the calculated transition probabilities, the lifetime of the 2s2p^3 {}^5S_2 metastable state is derived. The result is in excellent agreement with the latest experimental result. In the meantime the influence of anomalously strong relaxation effects on probabilities of the 2s2p^3 {}^5S_2－2s^22p^2 {}^3P_{1,2} lines in NII have been found.     

Extended Measurement of the v2 (1- ←0+) Band of H3O+ by Mid-Infrared Diode Laser Spectroscopy

Twenty-five new R-branch lines of the v2（1^-← 0^＋） band of H3O^＋ are measured using diode laser velocity modulation spectroscopy between 1070 and 1230 cm^-1. The H3O^＋ ions are produced in a high voltage ac discharge with water diluted in helium. The observed lines together with all the previously published measurements are fit to the standard vibration-rotational Hamiltonian of an oblate symmetric top, yielding a set of improved molecular constants. All the sextic centrifugal distortion constants for both 0^＋ and 1^- states are determined precisely. The observed R（13, 0） transition is shifted about -0.129 cm^-1 from its calculated value, indicating that a near degeneracy exists between the （13, 0）^＋ and （13, 3）^- ground-state rotation-inversion levels.     

Infrared diode laser spectroscopy of O2–N2O van der Waals complex in the v1 symmetric stretch region of N2O

The rovibrational spectrum of O2–N2O van der Waals complex is measured in the ν1 symmetric stretch region of N2 O monomer using a tunable diode laser spectrometer. The complex is generated by a slit-pulsed supersonic expansion with gas mixtures of O2, N2 O, and He. Both a- and b-type transitions are observed. The effective Hamiltonian for an open-shell complex consisting of a diatomic molecule in a ^3Σ electronic state and a closed-shell partner is used to analyze the observed spectrum. Molecular constants in the vibrationally excited state are determined accurately. The band-origin of the spectrum is determined to be 1284.7504（25） cm^-1, red-shifted from that of the N2 O monomer by ～ 0.1529 cm^-1.     

Improving luminescent property of SrIn2 O4 :Eu3+ by co-doped A+ （A = Li, Na, K） or Sm3+

A series of SrIn2 O4 :Eu3+ phosphors are synthesized by a high temperature solid-state method, and their luminescent properties are investigated. They can be excited by 395-nm radiation, and produce red emission (619 nm); however, they have a low absorption of near-ultraviolet light with the wavelength of 400nm-405 nm. When co-doped with A+ (A=Li, Na, K), the emission intensity of SrIn2O4 :Eu3+ is significantly enhanced, but its emission and excitation spectral profile is unchanged. With co-doping Sm3+ , not only is the emission intensity of SrIn2 O4 :Eu3+ enhanced, but also the absorption is broadened and strengthened in the range of 400 nm-405nm. The effect of Sm3+ -doped content on the emission intensity of SrIn2O4 :Eu3+ , Sm3+ is investigated, and the optimal Sm3+ content is 0.02 mol.