Rh XⅢ—Cd XVI离子4s24p3—4s4p4能级与跃迁的理论计算

用HFR（Hartree-Fock with relativistic corrections）方法对Rb V—Cd XVI离子4s²4p³和4s4p⁴组态能级结构做了全面系统的理论计算研究. 通过分析能级结构参数的HFR理论计算值与基于实验能级拟合得到的计算值之比值随着原子序数Z_c变化的规律,运用广义拟合外推方法预言了这些离子能级结构参数. 由此进一步计算了Rh XⅢ,Pd XIV,Ag XV和Cd XVI离子4s²4p³（⁴S_3/2,²P_1/2,3/2,²D_3/2,5/2）和4s4p⁴（⁴P_1/2,3/2,5/2,²P_1/2,3/2,²D_3/2,5/2,²S_1/2）组态能级以及电偶极跃迁波长与振子强度. 研究表明,对于4s²4p³组态,单组态近似可以得到较满意的结果;而对于4s4p⁴组态,只有在考虑了4s²4p²4d的组态相互作用效应时,计算结果的准确性才能明显得到提高. 同时,本文还运用全相对论grasp2K-DEV程序包计算了Rh XⅢ—Cd XVI离子组态能级. 对于Rh XⅢ离子4s²4p³（²P_1/2）,Pd XIV离子4s²4p³（⁴S_3/2,²P_1/2,3/2,²D_3/2,5/2）和4s4p⁴（²P_1/2,3/2,²D_3/2,5/2,²S_1/2）,能级均无实验值;对于Ag XV和Cd XVI离子,截至目前还没实验能级数据,没有实验能级值的所有数据均仅来自本文的计算数值. 本文计算结果与已有实验值吻合得很好.     

243—263nm S原子Rydberg态的(2+1)共振增强多光子电离

在243—263nm波长范围,测量了S⁺分质量激发谱,得到SO₂分子光解产生的S原子近50条(2+1)共振增强多光子电离谱线．除了来自S原子基态3p⁴³P_2,1,0直至n=10的Rydberg态³P,³D,³F的许多双光子跃迁谱线外,观察到若干新的¹P⁰,⁵S^关键词：     

中性硅3s23P2 3P2,1D2→3s3p3 3D3o跃迁能量,超精细结构常数与同位素移动的MCDHF计算

本文使用多组态Dirac-Hartree-Fock方法计算了²⁹Si的3s²3p^{2 3}P₂,¹D₂→3s3p³D₃⁰跃迁能量和³P₂,³D₃⁰超精细结构A常数以及Si同位素²⁹Si,³⁰Si和³¹Si相对于²⁸Si在3s²3p^{2 3}P₂→3s3p^{3 3}D₃⁰跃迁的同位素移动.通过尝试双电子激发（SD）和三电子激发（SDT）,分别考虑VV相关,CV相关和CC相关产生各种不同的扩展组态波函数得到的计算结果和实验值的比较,推测了对于中性硅原子这两个组态,内壳层2p2s,1s电子活动到外壳层的概率较小,而3s3p壳层中的电子都比较活跃,但主要是在n=3,4的壳层内活动,活动到更高n壳层的概率则比较小.     

PbCl2分子的光解离

用YAG激光的四次谐波光解离PbCl₂分子。实验确认了这种光解过程是双光子过程。通过对激光诱导荧光的测量,发现这一光解过程造成了Pb原子的亚稳态6p^{2 3}P₂与基态6p^{2 3}P。间的粒子数反分布。同时观察到基于6p^{2 3}P₂能级的受激共振辐射及受激喇曼散射。 关键词：     

CuⅩⅧ离子谱线波长和跃迁概率的理论计算

用多组态HFR方法对CuⅩⅧ离子n=3complex组态能级结构进行了综合的分析与计算.在已 有实验工作的基础上，运用参数拟合方法获得了能级结构参数的最佳计算值，由这些参数值 预测计算了CuⅩⅧ离子n=3complex组态能级以及3s²—3s3p,3s3p—3p ²,3p²—3p3d,3s3d—3p3d,3p3d—3d²组态能级跃迁的谱线波 长，振子强度和跃迁概率. 关键词： CuⅩⅧ离子 原子能级 跃迁谱线波长 振子强度和跃迁概率     

一价铝离子能级结构的多通道量子亏损理论分析

利用多通道量子亏损理论(MQDT)对一价铝离子(AIII)的各受干扰序列:3sns ¹S₀,3snp ³P_0,1,2^O,¹P₁^O,3snd ¹D₂和3snf³F_2,3,4^O的能级结构进行理论分析。结果表明:前两个序列所受到的干扰较弱,后三个序列则受到了来自干扰态3p4s ¹P₁^O,3p^{2 1}D₂和3p3d³F_2,3,4^O的强烈干扰,而3snf ¹F₃^O序列则受到来自电离限上方干扰态的影响。利用获得的MQDT参数推算出3p3d ¹F₃^O干扰态位于电离限上方5613cm^-1处,这一结果与其他作者的预言相符合。 关键词：     

Al等离子体类锂伴线的布居机制分析及实验应用

基于K壳层稳态碰撞辐射模型的程序,详细分析Al等离子体类锂伴线的主要布居机制,分别给出1s2p^{2 2}P-1s²2p²P,1s2s2p(¹S)²P-1s²2s²S与1s2p^{2 2}D-1s²2p² 关键词： 碰撞辐射模型 类锂伴线 线强比 激光等离子体     

Nb XIII离子3d94s2, 3d94s4p, 3d94p2 组态能级结构与跃迁的理论研究

用准相对论Hartree-Fock方法对Nb XIII离子二电子激发组态3d⁹4s², 3d⁹4s4p, 3d⁹4p² 的能级结构做了全面系统的理论计算研究.在对已有研究结果分析的基础上, 运用最小二乘方法对径向积分参数进行了优化计算, 得到了与这些组态有关的电偶极允许跃迁的谱线波长和跃迁概率.计算结果与最新的实验值做了对比分析, 表明本文计算结果是准确的. 研究发现, 波长40.92 nm的谱线, 属于3d⁹4s(¹D)4p²F_7/2–3d⁹ (²D)4s^{2 2}D_5/2 的跃迁谱线, 而不属于3d⁹4s (¹D)4p⁴D_7/2–3d⁹(²D)4s^{2 2}D_5/2 的跃迁谱线, 即上谱项能级为²F_7/2, 而不是⁴D_7/2. 关键词： Nb XIII离子 二电子激发组态 谱线波长 跃迁概率     

ZBLAN玻璃中Pr3+掺杂离子3P0和1D2能级的发光特性和寿命

对ZBLAN氟锆酸盐玻璃中Pr³⁺掺杂离子³P₀和¹D₂能级的寿命和发光特性进行了较详细的光谱学研究。首先测量了两种掺杂浓度(质量分数分别为1×10^-3,5×10^-3)的Pr³⁺:ZBLAN玻璃的吸收光谱,然后运用时间分辨激光光谱技术测量了³P₀和¹D₂能级在激光单光子共振激发下的荧光发射谱和能级寿命。将不同荧光发射谱带的强度和文献报道的Judd Ofelt理论计算辐射跃迁几率数值做了比较分析,证明了文献中理论计算结果的可靠性。由于浓度猝灭效应,在相同的激发条件下,掺杂浓度为1×10^-3样品的荧光发射强度明显大于5×10^-3样品的荧光发射强度。但是从我们的测量结果看,掺杂浓度对³P₀和¹D₂ 的能级寿命值无显著影响。掺杂浓度为1×10^-3时,Pr³⁺离子³P₀和¹D₂能级的寿命值分别为46,322μ_s。     

Zn2准分子的形成及其发射特性

通过光学抽运Zn(4s¹S₀—4p³P₁)共振线,在充有惰性气体的Zn蒸气中观察到两个连续的发射谱带。实验辨认它们可能归属于Zn₂准分子³∑_u⁺态,这与理论预言一致。研究谱带的时间与温度特性,以及惰性气体对谱带发射的影响。给出分子形成速率的上限和猝灭速率。结果表明,惰性气体分子在Zn₂准分子的形成及衰变中起了主要作用。 关键词：     

Lifetime of metastable magnesium atoms in superfluid helium

The metastable 3s3p³P_{0, 1, 2} states of the magnesium atom immersed into superfluid helium have been investigated. Absorption-fluorescence measurements were carried out to monitor the population of the³P₀,³P₁ and³P₂ level as a function of time. The population of these levels was found to decrease exponentially with a constant of =15±2 ms. This is about three times as long as the vacuum lifetime of the³P₁ level. In the resonant excitation band of the 3s3p³P states to the 3s4s³S state a blueshift of 70 nm compared to the emission and a large broadening were detected. The³P₂ and³P₀ states are not at all metastable any more. Additionally the weak intercombination transition of the³P₁ state to the¹S₀ ground state was investigated by monitoring this emission line as a function of time and of wavelength. The experiments resulted in the same exponential decay time as the excitation measurement. This outcome indicates a rather effective fine structure mixing of the considered Mg states in superfluid helium. Moreover, this raises the question whether common atomic quantum numbers are conserved and the selection rules are still valid.     

Orientation of Cs 6p 2P3/2 atomic photofragments in a magnetic field: interference in the photodissociation of diatomic molecules

In a magnetic field, Cs₂ molecules were excited from the ground X¹Σ⁺_g(v_X=0,J_X=55) level to the D ¹Σ⁺_u(v=46,J=54) level by dissociation laser light linearly polarized parallel to the field, for which the magnetic sublevels were degenerated and thus all the transitions between them were simultaneously stimulated. Probe laser light excited the dissociated Cs 6p²P_3/2 atomic fragments to 6p²D_3/2 level and the resultant 6p²P_1/2 - 6d²D_3/2 emission was detected as the function of the wavelength of the probe light. The populations of the 6p²P_3/2,mj magnetic sublevels were determined from the relative strengths of the 6p²P_3/2,mj - 6d²D_3/2,m'j transitions induced by the probe light. Non-zero orientation O₀ was found in the ensemble of dissociated Cs 6p²P_3/2 atomic fragments. The orientation O₀ increased as the magnetic field strength increased. It was demonstrated both experimentally and theoretically that the orientation O₀ was induced through the interference in the excitation and dissociation paths in the presence of an external magnetic field, even when all degenerated transitions between the magnetic sublevels of the molecules are simultaneously excited by the light linearly polarized parallel to the field.     

Electron excitation of neutral and ionic levels in Townsend discharges of argon at high E/N

We have measured the emission coefficients of the 3p levels of ArI: 3p₁, 3p₅, 3p₆, 3p₇, 3p₈, and 3p₁₀. The data for the 3p₅, 3p₆, 3p₇, 3p₈ and 3p₁₀ levels were converted to excitation coefficients by using quenching coefficients from the literature. Measurements were performed in the range of E/N between to above except for the 3p₇ level where measurements were done only up to . The data for the emission coefficients for Ar II levels include two 4p' levels with terms ² P ⁰ _1/2 and ² F ⁰ _7/2, and three 4p levels with terms ² P ⁰ _1/2, ⁴ P ⁰ _5/2 and ² D ⁰ _5/2. The measurements for the ionic levels were done for E/N above up to nearly . The absolute values of the coefficients were obtained from the intensity of the light emitted at the anode in the parallel plate self-sustained Townsend argon discharges. For low E/N the apparent emission coefficients (i.e. the normalized spatial profile of emission) for both neutral and ionic levels increase exponentially in almost the entire discharge gap. At about the exponentially increasing signal was obtained only near the anode, while at the spatial dependence was flat throughout the electrode gap. Received: 18 January 1999 / Received in final form: 12 April 1999     

Resonance-enhanced multiple-photon ionisation spectroscopy of excited sulphur atoms

Sulfur atoms are produced in the excited 3s ²3p ^{4 1} D ₂ and 3s ²3p ^{4 1} S ₀ levels by two-photon photodissociation of CS₂ in the gas phase in the region 285–305 nm. These excited atoms are detected by three-photon (two to resonance) ionisation at selected laser wavelengths. Many new transitions have been observed which have not been reported previously. The new dark states that have been accessed by two-photon absorption have been characterised and the energy levels with respect to the ground ³ P ₂ state have been determined. Configuration interaction between 6p ³ P ₁, 6p ⁵ P ₁, and 4p¹ P ₁ states, and also between 6p ³ P ₂, 6p ⁵ P ₂, and 4p¹ D ₂ states has been observed. It is found that intermediate states reached from the ¹ S ₀ level through two-photon absorption lie above the first ionisation potential of S⁺(⁴ S ⁰). It is proposed that autoionisation into the ⁴ S ⁰+e^– continuum is a dominant mechanism in the decay of these levels, although ionisation by a further photon absorption is not ruled out.     

Mechanisms of broadening of emission lines of a laser-induced plasma generated on the surface of rigid targets

This article reports the results of an experimental investigation of the basic mechanisms that cause the broadening of emission lines of a laser-induced plasma generated on the surface of rigid targets in a gaseous atmosphere. The contribution of Stark and resonance mechanisms of emission-line broadening for the resonance doublet Al I 3s²3p²P_3/2,1/2-3s²4s²S_1/2 and triplet Mg I 3s3p³P _0,1,2 ⁰ -3s4s³S₁ is discussed. The concentrations of neutral Al atoms in the laser-induced plasma are evaluated by the magnitude of resonance line broadening. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 2, pp. 234–237, March–April, 2000.     

Relativistic R-matrix close-coupling calculations for photoionization of Ne-like Al IV

We present relativistic close-coupling photoionization calculations of Al IV using the Breit-Pauli R-matrix method to obtain photoionization cross-section of Al IV from the ground state and the lowest two J=0 (even) excited states. A multi-configuration eigenfunctions expansion of the core Al V is employed with spectroscopic configurations 2s²2p⁵, 2s2p⁶, 2s²2p⁴3s, 2s²2p⁴3p, 2s²2p⁴3d and 2s²2p⁴4s. We have included, for the first time, the lowest 68 level target states of Al V in the photoionization calculations of Al IV. Extensive configuration interaction wavefunctions are used to describe both the initial Al IV states and the final Al V states. Cross-sections are compared from three level calculations including only 2s² 2p^{5 2}P^o _3/2, _1/2 and 2s 2p^{6 2}S_1/2 levels of Al V. The present calculation using the lowest 68 target levels of Al V are presented for the first time and should provide reasonably complete database for practical application for photoionization cross-section for Al IV, where high-energy cross-sections along with near-threshold photoionization cross-section is required.     

Mössbauer spectra study on Xiu-Yan Jade

Having beautiful colours and fine features, Xiu-Yan Jade is famous in the world. Mineralogically, Xiu-Yan Jade is serpentine jade. XRD, IR and TEM study indicate that the jade consists mainly of antigorite (m{Mg_3(1?1/m)[Si₂O₅](OH)_1+3(1?2/m)}) with a minor amount of chrysotile. Two favourite samples (P_XA, P_X1?t) are chosen for research on⁵⁷Fe Mössbauer spectra. Two sets of quadrupole doublets are obtained from the spectra, The parameters of two samples, 1. 124 mm/s and 1. 119 mm/s of I. S. and 2. 732mm/s and 2. 716mm/s of Q. S. for Fe²⁺ in the octahedral and 0. 364mm/s and 0. 351mm/s of I. S. 0. 632 and 0. 546mm/s of Q. S. for Fe³⁺ in the octahedral, are only antigorite. Studies indicate that: (1) iron—ion in antigorite enters the lattice as impurity: (2)Fe²⁺ and Fe³⁺ substitute for Mg in the coordination octahedron: and (3) the colour of jade is related to content of Fe, and Fe³⁺/Fe²⁺≤1 is favourite for colour—forming.     

高离化态类镍离子电子碰撞激发过程的相对论扭曲波理论研究

利用相对论扭曲波方法和新发展的研究电子碰撞激发过程的计算程序REIE06,系统计算了电子碰撞激发高离化态类镍Gd³⁶⁺和Rn⁵⁸⁺—U⁶⁴⁺(Z=86—92)离子从基态到4l(l=s,p,d,f)次壳层精细结构能级的碰撞强度和截面.研究了随等电子系列变化时,从基态到与X射线激光有关的3d⁹4p和3d⁹4d激发态能级的电子碰撞激发截面随Z的变化,讨论了强的组态相互作用对高离化态类镍离子截面的影响.通过对Gd³⁶⁺离子涉及X射线激光跃迁的相关能级电子碰撞激发速率系数的计算,分析了等离子体中电子温度对碰撞过程的影响.同时,目前部分计算结果与以往的理论结果进行了比较,得到了很好的一致性. 关键词： 电子碰撞激发 相对论扭曲波方法 高离化态类镍离子     

Radiative de-excitation of the 1s22s3 p 3P0 level in beryllium-like ions: A competition between an E2 and a two-electron one-photon E1 transition

I have performed a complete Multi-Configuration Dirac-Fock calculation of the radiative de-excitation of the 1s²2s3p³P₀ level in beryllium-like ions. Initial and final wave functions are fully optimized, and include valence and core polarization correlation (Coulomb and Magnetic). Non-orthogonality between initial and final state spin-orbitals is exactly accounted for. I show that the main mode of de-excitation of the 1s²2s3p³P₀ level at high Z is an E2 transition to the 1s²2s2p³P₂ and that a two-electron one-photon E1 transition to the 1s²2p^{2 3}P₁ plays an important role at low Z. The latter transition appears to be the difference of two large matrix elements which cancel almost exactly and thus has a very complicated Z dependence, which is studied in the present paper. This revised version was published online in August 2006 with corrections to the Cover Date.