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1.
利用多组态相互作用方法及Rayleigh-Ritz变分法,计算了类锂离子2p2np4So(n=2-4)和1s2pmp4P(m=2,3)的能量.运用截断变分方法得到能量的改进量.计算了相对论修正、质量极化效应,从而获得了高精度的能量计算值.同时还计算了该系统之间的辐射跃迁波长、振子强度和辐射跃迁率.计算结果与实验符合得很好.  相似文献   

2.
锂内壳高激发2smd4De,2pnd4Do系列的能量和辐射跃迁   总被引:1,自引:0,他引:1       下载免费PDF全文
王菲  芶秉聪  韩利 《物理学报》2001,50(9):1685-1688
采用鞍点变分方法计算了锂内壳高激发四重态1s2smd4De(m=3—7)和1s2pnd4Do(n=3—5)的能量,利用截断变分方法得到能量改进量,并计算了相对论修正、质量极化效应,从而获得了高精度的能量计算值.同时还对该系统之间的辐射跃迁波长、振子强度和辐射跃迁率进行了计算.计算结果与实验符合得很好. 关键词: 内壳高激发态 鞍点变分方法 振子强度 精细结构  相似文献   

3.
杨富利  易有根 《物理学报》2008,57(3):1622-1625
采用全相对论量子力学GRASP2程序,广义平均能级EAL模型,在核的有限体积效应,Breit和QED效应的高阶扰动基础上,考虑到原子实的极化,系统地计算了高剥离类钾离子4s 2S1/2─3d 2D3/2电四极矩E2光谱跃迁的能级间隔,跃迁概率和振子强度,结果表明:考虑原子实极化效应后,计算的精细能级结构间隔与实验数据之间的系统误差基本消除,其跃迁概率和振子强度属首次报道. 关键词: 高剥离态 能级间隔 振子强度  相似文献   

4.
DyP5O14晶体的光谱强度参数   总被引:1,自引:0,他引:1       下载免费PDF全文
本文根据Judd-Ofelt理论,利用吸收光谱,计算了DyP5O14晶体中Dy3+的三个唯象强度参数Ωλ(λ=2,4,6),求得了计算和实验振子强度,进而计算了约化矩阵元和荧光辐射跃迁几率。 关键词:  相似文献   

5.
秉聪 《物理学报》1998,47(3):403-410
采用多通道鞍点和鞍点复数转动方法,计算了类锂离子(Z=3—10)2s2s2p2P0和2s2p2p2D三激发共振态系列的能量、精细结构和寿命.Auger宽度由耦合主要的通道得到,相对论效应计算到一级微扰,质量极化效应计算到无穷级. 关键词:  相似文献   

6.
利用全实加关联方法得到的波函数计算类锂离子(Z=11~20)1s23d-1s2nf(4≤n≤9)的偶极跃迁振子强度,三种规范下的计算结果符合的很好.将分立态的振子强度结果与单通道量子亏损理论相结合,计算在电离阈附近(|E|≤I/2)分立态间的束缚态-束缚态跃迁振子强度与束缚态-连续态跃迁的振子强度密度,实现了具有较大核电荷数的类锂离子量子跃迁特性的全能域理论预言.  相似文献   

7.
钱新宇  孙言  刘冬冬  胡峰  樊秋波  苟秉聪 《物理学报》2017,66(12):123101-123101
采用Rayleigh-Ritz变分方法计算了B原子(离子)内壳层激发高自旋态(~(4,5,6)L,L=S,P)里德伯系列的能量和精细结构劈裂,利用截断变分方法改进非相对论能量,并利用一阶微扰理论计算了相对论能量修正和质量极化效应修正,利用屏蔽的类氢公式计算了量子电动力学效应和高阶相对论效应,从而得到了高精度的组态能量.利用精确计算的波函数,计算了这些高自旋态的电偶极辐射跃迁波长、振子强度和辐射跃迁概率.通过长度规范和速度规范计算的振子强度的一致性证明了本文计算的波函数是精确的.相比其他理论计算结果,本文计算的高自旋态的能级及跃迁波长数据与实验数据符合得更好.对于一些高位的内壳层激发高自旋态,相关的能级和跃迁数据为首次报道,本文的计算结果对相关实验光谱谱线标定具有重要意义.  相似文献   

8.
利用全相对论多组态Dirac-Fock方法系统地计算了高离化类铍离子的磁四极M2 2s21S0—2s2p3P2 (Z=10—103)自旋禁戒跃迁的能级间隔、跃迁概率和振子强度,计算中考虑了重要核的有限体积效应,Breit修正和QED修正,所得结果和最近的实验数据以及理论值进行了比较,结果表明:高原子序数的高电荷离子(Z≥70)磁四极M2自旋禁戒跃迁几乎可以和中性原子的光学允许跃迁相比拟,不仅在天体等离子体中,在ICF和MCF高温激光等离子体中,磁四极自旋禁戒跃迁和其他自旋禁戒跃迁(磁偶极、电四极)一样不容忽视,在双电子复合、不透明度、自由程等理论计算中应该考虑其影响. 关键词: 磁四极M2 能级间隔 跃迁概率 振子强度  相似文献   

9.
采用鞍点变分方法和鞍点复数转动方法,并考虑相对论修正和质量极化效应,计算了类铍内壳激发态1s2p33Po的俄歇宽度、俄歇电子能量和俄歇分支率.同时还对1s2p33Po态到1s22p3p3Pe态(Z=4~10)的振子强度和辐射跃迁率进行了计算.计算结果和其他理论结果和实验数据符合的很好.  相似文献   

10.
采用Rayleigh-Ritz变分方法和组态相互作用方法,并进一步考虑相对论修正和质量极化效应,研究了氦原子单激发和双激发态里德伯系列的相对论能量,计算结果与其他理论和实验符合得很好.此外,还计算了该系统之间的振子强度、辐射跃迁率及跃迁波长,振子强度三个规范的计算结果显示出很好的一致性. 关键词: 氦原子 变分计算 振子强度 辐射跃迁率  相似文献   

11.
高虹 《物理学报》1997,46(11):2138-2145
运用量子亏损理论,并与参考系变换及本征通道R-矩阵法相结合,建立了描述氢分子里德伯态的预解离过程的理论方法.通过对氢分子的3pπD1πu+和4pσ B″1Σu+电子态的预解离过程的研究,阐明其解离的机理,并给出预解离的线宽. 关键词:  相似文献   

12.
Thermoelectric power using reversible silver electrodes and electrical conductivity on the compressed pellets of (Me4N)2Ag13I15, and (Et4N)2Ag13I15 have been measured between room temperature and below 160°C. The results of θ can be expressed by the equations:?θ = 0.115 (103/T)+0.2905VK?1 and ?θ = 0.150 (103/T) + 0.305mV K?1; and those of conductivity by the equations; σ = 28.7 exp (?0.17eV/kT) ohm?1cm?1 and σ = 216.6 exp (?0.24eVkT) ohm?1cm?1; respectively for Me- and Et-electrolytes. The results are discussed and compared with those of previous authors.  相似文献   

13.
The heat capacity of the layer compounds tetrachlorobis (n-propylammonium) manganese II and tetrachlorobis (n-propylammonium) cadmium II, (CH3CH2CH2NH3)2MnCl4 and (CH3CH2CH2NH3)2CdCl4 respectively, has been measured over the temperature range 10 K ?T ? 300 K.Two known structural phase transitions were observed for the Mn compound in this temperature region: at T = 112.8 ± 0.1 K (ΔHt= 586 ± 2 J mol?1; ΔSt = 5.47 ± 0.02 J K?1mol?1) and at T =164.3 ± (ΔHt = 496 ± 7 J mol?1; ΔSt =3.29 ± 0.05 J K?1mol?1). The lower transition is known to be from a monoclinic structure to a tetragonal structure, while the upper is from the tetragonal phase to an orthorhombic one. From comparison with the results for the corresponding methyl Mn compound it is deduced that the lower transition primarily involves changes in H-bonding while the upper transition involves motion in the propyl chain.A new structural phase transition was observed in the Cd compound at T= 105.5 ± 0.1 K (ΔHt= 1472.3 ± 0.1 J mol?1; ΔSt = 13.956 ± 0.001 J K?1mol?1), in addition to two transitions that have been observed previously by other techniques. The higher of these transitions(T = 178.7 ± 0.3 K; ΔHt = 982 ± 4 J mol?1 ΔSt = 6.16 ± 0.02 J K? mol?1) is known to be between two orthorhombic structures, while the structural changes at the lower transition (T= 156.8 ± 0.2 K; ΔHt = 598 ± 5 J mol?1, ΔSt = 3.85 ± 0.03 J K?1 mol?1) and at the new transition are not known. It is proposed that these two transitions correspond respectively to the tetragonal to orthorhombic and monoclinic to tetragonal transitions in the propyl Mn compounds.In addition to the structural phase transitions (CH3CH2CH2NH3)2MnCl4 magnetically orders at t? 130 K. The magnetic contribution to the heat capacity is deduced from the heat capacity of the corresponding diamagnetic Cd compound and is of the form expected for a quasi 2-dimensional Heisenberg antiferromagnet.  相似文献   

14.
More than two thousand Stark resonances of the ν4 and 2ν2 band transitions of 14NH3 and 15NH3 were observed at Doppler-limited resolution with a CO laser. Fourier transform infrared spectroscopy on 15NH3 is also carried out. Thirty-six new microwave transitions including seven perturbation-enhanced transitions are observed in the v4 = 1 excited vibrational state of 14NH3 and 15NH3. Accuracies of all available spectroscopic data on the v4 = 1 and the v2 = 2 states are evaluated and analyses of the vibration-rotation spectra are performed. The Coriolis interaction between the closely lying v4 = 1 a (antisymmetric level) and v2 = 2 s (symmetric level) states is explicitly included in the analysis. Smaller Coriolis interactions between the v4 = 1 a and the v2 = 1 s states and between the v2 = 2 s and the v2 = v4 = 1 a states (i.e., (v1, v2, v3, v4) = (0 1 00 11)) are also taken into consideration. The accuracy in determination of the principal molecular constants is 10?6. The parameters thus obtained reproduce the frequencies of the vibration-rotation transitions and inversion transitions within the accuracy of 0.0024 cm?1.  相似文献   

15.
The absorption spectrum of Ni2+ doped in Cs2Mg(SO4)2 · 6H2O single crystals has been studied at room and liquid nitrogen temperatures in the range 7000–34000 cm?1. The observed spectrum is satisfactorily interpreted in terms of cubic ligand field model including spin-orbit coulping. The ligand field parameters evaluated to best fit the observed spectrum are B = 955 cm?1, C = 3572 cm?1, Dq = 910 cm?1 and ξ = 550 cm?1. The non-ligand field band observed at 77K has been interpreted to be the superposition of vabrational mode of SO42? radical on 3T1g(F) band.  相似文献   

16.
<正>This paper investigates the luminescence characteristics of Eu2+ activated Ca2SiO4,Sr2SiO4 and Ba2SiO4 phosphors. Two emission bands are assigned to the f-d transitions of Eu2+ ions doped into two different cation sites in host lattices,and show different emission colour variation caused by substituting M2+ cations for smaller cations.This behaviour is discussed in terms of two competing factors of the crystal field strength and covalence.These phosphors with maximum excitation of around 370 nm can be applied as a colour-tunable phosphor for light-emitting diodes(LEDs) based on ultraviolet chip/phosphor technology.  相似文献   

17.
郭常霖  吴毓琴 《物理学报》1980,29(11):1490-1496
用衍射仪和Guinier聚焦相机收集了含秘层状结构铁电体PbBi4Ti4O15SrBi4Ti4O15的X射线粉末衍射图谱(Cu Ka),给出了d值大1.13?的88和76条衍射线的衍射数据和指标。它们都属正交晶系,空间群Bb21m(C2v12),点阵常数和X射线理论密度为PbBi4Ti4O15α=5.431?,b=5.459?,c=41.36?; z=4;Dx=7.986g/cm3.SrBi4Ti4O15:α=5.428?,b=5.438?,c=40.94?;Z=4;Dx=7.447g/cm3.  相似文献   

18.
The so-called pentad of 12CD4 consists of the vibrational states v1 = 1(symmetry A1), v3 = 1(F2), v2 = 2(A1 + E), v2 = v4 = 1(F1 + F2), and v4 = 2(A1 + E + F2). All states are located in the 1950 to 2250-cm?1 region and all are strongly interacting. In the present work we have assigned more than 5000 infrared rotation-vibrational transitions and 163 isotropic Raman transitions from the vibrational ground state to the pentad. We have used infrared and Raman spectra of a resolution better than 0.01 cm?1. From the experimental wavenumbers 2567 pentad rotation-vibrational energy levels with J ≦ 20 have been determined. These levels are reported in the paper. The levels have been used for refinements of the spectroscopic constants of two physically different effective Hamiltonians for the pentad states. For all levels with J ≦ 12 an unweighted standard deviation of 0.004 cm?1 is obtained for both Hamiltonians, whereas the standard deviation increases more or less rapidly with J above 12 due to the imperfections of the Hamiltonians. The values of the spectroscopic constants of both Hamiltonians (85 and 106, respectively) are reported and the effects of the approximations are discussed.  相似文献   

19.
The non-isothermal decomposition of NiC2O4·2H2O-FeC2O4·2H2O (1:2 mole ratio) mixture was studied on heating to the formation of NiO-Fe2O3 mixture at 350 °C in air atmosphere using thermogravimetry. Kinetic analysis of data according to the integral composite method showed that the oxidative decomposition of FeC2O4 and NiC2O4 are best described by the three-dimensional phase boundary model. The activation parameters were calculated and discussed. The solid products at different decomposition stages were identified using XRD, Mössbauer and FT-IR spectroscopic techniques. Some characteristic XRD lines of NiFe2O4 start to appear at 800 °C beside the characteristic lines of NiO and Fe2O3, whereas at 1000 °C, only the characteristic lines of single phase cubic NiFe2O4 appeared. The Mössbauer spectrum at 1000 °C fitted into two Zeeman sextets characteristic of Fe3+ on the tetrahedral (A) and octahedral (B) sites of NiFe2O4 inverse spinel. Consistent results were obtained using FT-IR where the absorption bands appeared at 602 and 407 cm−1 for the mixture calcined at 1000 °C. These can be assigned to the intrinsic vibrations of tetrahedral and octahedral sites of NiFe2O4, respectively.  相似文献   

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