共查询到19条相似文献,搜索用时 328 毫秒
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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)4p2F7/2–3d9 (2D)4s2 2D5/2 的跃迁谱线, 而不属于3d94s (1D)4p4D7/2–3d9(2D)4s2 2D5/2 的跃迁谱线, 即上谱项能级为2F7/2, 而不是4D7/2.
关键词:
Nb XIII离子
二电子激发组态
谱线波长
跃迁概率 相似文献
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利用电热法将含金物质加热,产生Au原子束,再以两束UV脉冲激光垂直照射,将处于基态的Au原子共振激发至高Rydberg态。滞后于激光脉冲200ns的高压脉冲电场(6500V/cm)加到反应区,使处于Rydberg态的Au原子电离。激光波长在一定范围内扫描,共测出了Au原子的n2D3/2(n=18—38)和n2S1/2(n=21—34;36—38)两通道的38条能级的位置。用参数拟合得到2D3/2和2S1/2两系列的极限分别为:ED=74409.8(3)cm-1,ES=74410.0(2)cm-1,计算了每条能级的量子亏损。我们的实验还证明了场电离是一种十分有效的电离手段,比用通常的激光光电离效率要高得多。这在共振电离谱学(RIS)的研究中是一种很有效的方法。
关键词: 相似文献
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Abstract The optical absorption of the diluted magnetic semiconductor Zn1?xCOxSe (x = 0.02) has been measured at room temperature under hydrostatic pressure up to 14GPa in a membrane diamond-anvil cell. We found two absorption features: (i) an absorption structure in the energy range 1.6?1.8eV, with a negligible pressure shift (i.e., 0.45 ± 0.05 meV/GPa) which we have identified as the Co2+(3d7) internal transition 4A2(F)→+4T1(P) and (ii) an onset in the energy range 2?2.7eV which redshifts with pressure (?8.1±0.6meV/GPa). We have attributed such absorption edge to charge transfer between the ZnSe valence band and the Co2+(3d7) levels. 相似文献
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应用多组态Dirac-Fock(MCDF)方法,对Xe10+离子进行了理论计算,获得了跃迁波长和概率等数据.通过逐步引入4dn—5pn(n=1, 2, 3)电子相关的相互作用组态,重点研究了电子相关效应对4d8—4d75p跃迁系跃迁概率的影响.结果显示电子相关效应显著,表明了欲得到精确的4d8—4d75p的振子强度(跃迁概率)数据,理论计算中至少要包括到4d2—5p2的电子相关组态的影响.与实验测得的跃迁波长比较发现,理论结果与之有着较好的一致性;同时理论跃迁概率在两种规范下的结果符合得相当精确,显示了计算结果的可靠性.
关键词:
多组态Dirac-Fock(MCDF)方法
电子相关
跃迁概率 相似文献
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V. A. Zilitis 《Optics and Spectroscopy》2002,92(3):353-356
The structure of the energy level system for 39 ions of the scandium isoelectronic sequence is studied on the basis of the relativistic self-consistent field method taking into account the configuration interaction. The Dirac-Fock equations are solved with subsequent diagonalization of the energy matrix. The ground-state ionization potentials are determined for each ion. The energy levels corresponding to the 3d4s 2, 3d 24s, and 3d 3 configurations are also calculated. The obtained energy values are compared with the experimental data as well as with the results of calculations carried out by other authors. 相似文献
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Relativistic multichannel treatment of autoionization Rydberg series of 4s^2nf(n=4- 23)J^π -(7/2)° for scandium 下载免费PDF全文
Based on relativistic multichannel theory, this paper calculates the energy levels of autoionization Rydberg series 4s^2nf(n=4- 23)J^π -(7/2)° of scandium at different levels of approximation within the framework of multichannel quantum defect theory. The present results show that the dipole polarizations play an important role. Considering the dynamical dipole polarization effects, this paper finds that the difference between calculated and experimental quantum defects for the 4s^2nf(n=4- 23)J^π -(7/2)° series is generally about 0.01- 0.03. Furthermore, the reason that 4s^216f is obscured in experimental spectra is suggested to be the interaction with the neighbouring resonance state converged to 3d^2(^1G4) of Sc^+. 相似文献
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STUDY OF HIGH-LYING EXCITED STATES OF RARE-EARTH ELEMENT Dy BY LASER RESONANCE IONIZATION SPECTROSCOPY 下载免费PDF全文
This paper describes the investigation of high-excited states of Dy. which includes the measurement of high Rydberg states and autoionizing states, by means of laser resonance ionization spectroscopy (LRIS). Two high Rydberg series (n>40), 4f10(5I8) 6sns and 4f10(5I8) 6snd, have been obtained by exciting the state of 4f10(5I8) 6s6p (3P02) 5I08 using two-step laser excitation-electric field ionization method. With the data obtained, we determined the first ionization potential of Dy. It is 47901.7±0.6 cm-1, that is. about one order more accurate than the results given in the literature. Using the same technique, we found 97 autoionizing states by exciting the state of 4f95d6s(7H07). 相似文献
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Fernando Colmenares 《Molecular physics》2013,111(15):1513-1519
CASSCF-MRMP2 calculations have been performed to analyse the reaction of fluoromethane with a bare ruthenium atom. Potential energy curves emerging from the ground state and the first excited state of the reactants, Ru(5F, 3F;d7s1) + CH3F, were calculated for representative electronic states associated with different approaching modes of the fragments. Whereas no favourable channels correlating with the ground state asymptote were detected for the insertion of the ruthenium atom into the C–H bond of the methyl fluoride molecule, the oxidative addition of the C–F bond of this molecule to the metal atom along the reaction path evolving from the ground state of the fragments leads to the stable inserted product CH3–Ru–F. Although forming less stable products, insertion of ruthenium into the C–H and C–F bonds of the fluorocarbon molecule can occur through electronic states which emerge from the excited triplet state asymptote. 相似文献
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The absorption, luminescence, and luminescence excitation spectra of ruthenium(II) complexes cis-[Ru(bpy)2(L)Cl]+[bpy=2,2′-bipyridyl; L=NH3, pyrazine, pyridine, 4-aminopyridine, 4-picoline, isonicotinamide, 4-cyanopyridine, 4,4′-bipyridyl, or trans-1,2-bis(4-pyridyl)ethylene] in alcoholic (4: 1 EtOH-MeOH) solutions are studied. At 77 K, the quantum yields and decay times of the luminescence of the complexes are measured and the deactivation rate constants of the lowest electronically excited metal-to-ligand charge transfer state (3MLCT) are determined. The linear correlation between the energy of the lowest state 3MLCT d π(Ru)>π*(bpy) of the cis-[Ru(bpy)2(L)Cl]+ complexes and the parameter pKa of the free 4-substituted pyridines and pyrazine used as ligands is established. 相似文献
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The complete energy matrix (210 × 210) for d6(d4) configuration ions in a trigonal ligand field is constructed. The energy levels and zero-field splitting parameters in ferrous fluosilicate and ferrous carbonate are studied. The contributions of spin singlets to zero-field splitting parameters in a trigonal ligand field are investigated for the first time. The calculation results indicate that the spin-singlet contribution to second-order zero-field splitting parameter D is negligible, but the contributions to fourth-order zero-field splitting parameter a ? F cannot be neglected. Moreover, it is found that the stronger the trigonal ligand field, the larger are the spin-singlet contributions to the zero-field splitting parameters. 相似文献
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Thermal quenching of 5d-4f luminescence from Nd3+, Er3+ and Tm3+ ions doped into KYF4 crystals has been investigated in the temperature range up to ∼750 K where this luminescence is completely quenched. The obtained temperatures of thermal quenching (Tq) are ∼270, 495, 450 K for Nd3+, Er3+, Tm3+, respectively. At high temperatures, thermal quenching of 5d-4f luminescence from Nd3+ and Er3+ is accompanied by the appearance of 4f-4f luminescence from the lower-energy 4f levels. It has been shown that the dominating mechanism of thermal quenching for Nd3+ and Er3+ ions is thermally stimulated non-radiative transitions (intersystem crossing) from the 5d states to lower-energy 4f levels, namely 2G(2)9/2 and 2F(2)7/2, respectively, whereas for the Tm3+ ion, thermally stimulated ionization of 5d electrons to the conduction band states is responsible for thermal quenching of 5d-4f luminescence. The energy gap between the lowest Tm3+ 5d level and the bottom of the KYF4 conduction band has been estimated to be 0.66 eV. 相似文献