共查询到20条相似文献,搜索用时 31 毫秒
1.
W. E. van der Veer R. J. J. van Diest A. Dönszelmann 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,25(3):201-203
The radiative lifetimes of the levels in the 3d 94s(1 D)4p configuration of Cu I are measured. The levels are excited from the metastable 3d 94s 2 2 D 3/2,5/2 levels. The metastable Cu atoms are generated in a pulsed hollow cathode discharge. The levels investigated are populated with a 35-ps laser pulse at wavelengths around 220 nm. The laser induced fluorescence signal is detected. The lifetime of the 3d 94s(3 D)4p 4 D 1/2 level is also determined by direct excitation from the ground state. A comparison with calculated literature values is given. 相似文献
2.
A. Wännström D. S. Gough P. Hannaford 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1992,22(4):723-726
Magnetic hyperfine interaction constants (A factors) and electric quadrupole interaction constants (B factors) have been determined for sixteen levels in tantalum I using the method of saturated absorption spectroscopy in a sputtered vapour. Five of these levels belong to the lowest configuration 5d 3 6s 2 which has been studied previously by other workers, and for one of these levels, thea 4 P 5/2 at 9253 cm?1, our results are new. For the eleven levels belonging to the excited configurations 5d 3 6s 6p and 5d 2 6s 2 6p our values are the first data reported in the literature. 相似文献
3.
(U)PBE0/cc-pVDZ method is used to study the structure of C60Cl30, C60(OH)30 molecules and Fe@C60(OH)30 endocomplex. The triplet state of the endocomplex is shown to be the lowest in energy among its four states corresponding to different spin multiplicities and positions of Fe nucleus within the fullerene cavity. This state is characterized by bonding between the iron atom and one of two benzenoid cycles of the carbon cage, six internuclear Fe–C distances (208 pm), and 1s22s22p63s23p63d7.24s0.14p0.3 electron configuration of iron with spin population of 2.36. 相似文献
4.
J. Maier C. S. Kischkel M. Baumann 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1991,21(2):145-151
Using laser induced fluorescence spectroscopy the hyperfine structure of the even parity levels 4f 146s6d 3 D 1, 4f 14 6s8s 3 S 1 and 4f 13 5d6s6p (7/2, 5/2)J=1,2,3 as well as of the odd parity level 4f 14 6s6p 3 P 2 in neutral ytterbium has been investigated. The isotope shift of the transitions 4f 146s6p 3 P 0 → 4f 14 6s6p 3 D 1 and 4f 14 6s6p 3 P 2 → 4f 14 6s8s 3 S 1, 4f 13 5d6s6p (7/2, 5/2)J=1,2,3 could be measured with high accuracy. The results for the 4f 14 6s6p 3 D 1 level show a considerable influence of second order effects of the hyperfine interaction. The isotope shifts of the 4f 14 6s8s 3 S 1 and 4f 13 5d6s6p (7/2, 5/2)J=1 levels indicate a possible configuration mixing for these levels. 相似文献
5.
C.David Garner Ian H. Hillier Frank E. Mabbs Martyn F. Guest 《Chemical physics letters》1975,32(2):224-226
The results of ab initio molecular orbital calculations for [CrOfs]2? and polarised single crystal electronic spectra of [MoOCl3(Op(NMe2)3)2] and Ph4As[MoOCl4(H2O)] are presented. These data are consistent with the electronic transitions of the MO3+ moieties, O2pπ → Mdxy and Mdxy → Mddxy,dyz being the lowest energy transitions in the spectra of their respective complexes, both these transitions being of low intensity. 相似文献
6.
S. Baier M. Martins B. R. Müller P. Zimmermann 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,10(4):445-449
Using a combination of collisional and laser excitation the lifetimes of 17 autoionizing Cu I states in the configurations 3d 9 4s 6s and 3d 9 4s4d were measured. The lifetimes are in the range of 1–50 ps and depend strongly on the coupling properties, the mixing with different configurations, and the radial integrals of the discrete with the continuum states. For the level 3d 9 4s 4d 4 S 3/2 the influence of an electric field via Stark mixing of 3d 9 4s 5p 4 P 1/2 on the autoionizing rate was investigated. The experimental values are compared with theoretical results which follow from ab initio calculations for the transition probabilities and least square fit values deduced from the experimental positions. Good agreement is found only for theJ=3/2 levels of both configurations 3d 9 4s 4d and 3d 9 4s 6s. 相似文献
7.
A. Baier H. O. Behrens G. H. Guthöhrlein L. Windholz 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1992,23(2):151-153
The TaI line 6356.14 Å, up to now classified as the transition 5d 36s 2 a 4 P 5/2?5d 36s(a 5 F)6p z 4 F 7 2/0 , is a blend with a second transition, which is related to the additional levels 5d 4(b 3 G)6s a 4 G 9/2?39641.24 cm?1 J=7/2°. Using laser excitation with optogalvanic and laser-induced fluorescence detection, the hyperfine constants of the four levels involved and the distance of the center wavelengths of the two fine structure transitions could be determined. 相似文献
8.
Charles W. Bauschlicher Jr 《Theoretical chemistry accounts》1995,92(3):183-198
Large atomic natural orbital (ANO) basis sets are tabulated for the Sc to Cu atoms. The primitive sets are taken from the large sets optimized by Partridge, namely (21s13p8d) for Sc and Ti and (20s12p9d) for V to Cu. These primitive sets are supplemented with threep, oned, sixf, and fourg functions. The ANO sets are derived from configuration interaction density matrices constructed as the average of the lowest states derived from the 3d n 4s 2 and 3d n+14s 1 occupations. For Ni, the1 S(3d 10) state is included in the averaging. The choice of basis sets for molecular calculations is discussed. 相似文献
9.
The electronic structure of the tetrahedral molecule VCL4 is investigated within the CNDO-MO approximations. The metal and ligand valence orbitals, 3d, 4s, 4p; and 3s, 3p; respectively, have been systematically varied in an attempt to minimize the total energy; “optimum” V 4s(χ4 = 1.10) and 4p(d 3 p 2) orbitals have been established, but V 3d(d n ) and Cl(-δ) valence orbitals are only seen to favor lower energy for expanded orbitals. Since determining the one-electron molecular orbital level which is occupied by the vanadium lone electron is a major aspect of this investigation, all calculations have been performed in triplicate: calculations assuming the unpaired electron occupies the 3a 1, 2 e and 4t 2 molecular orbital (ground state electronic configurations2 A 1,2 E, and2 T 2, respectively). The Hartree-Fock equations have been solved by Roothaan's SCF method for open shells, but off-diagonal multipliers between filled and partly filled molecular orbitals of the same symmetry have been neglected. As a qualitative estimate of the error introduced by this simplification, the pertinent overlap integrals between the eigenfunctions from calculations for the three possible configurations,2 A 1,2 E, and2 T 2, are investigated as functions of the component 3d(d n ) and Cl(-δ) valence orbitals. The overlap integrals from the relevant2 A 1 and2 T 2 calculations are reasonably small, but the neglect of off-diagonal multipliers in calculations on the2 E state is found to be a poor approximation. An ordering of the non-filled molecular orbitals in VCl4 of 4t 2 < 3a 1 < 2e < 5t 2 seems most consistent with the numerous calculations. This suggested ground state electronic configuration of2 T 2 introduces new aspects to the consideration of a (dynamic) Jahn-Teller effect in VCl4. Experimental data pertinent to the electronic structure of VCl4 has been briefly summarized, but unfortunately it is inadequate to confirm or deny the present calculations. 相似文献
10.
Omar M. Al-dossary Neji Khelifi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(1):73-84
The potential energy curves have been calculated for the electronic states of the molecule LiK within the range 3 to 300 a.u., of the internuclear distance R. Using an ab initio method, through a semiempirical spin-orbit pseudo-potential for the Li (1s 2) and K (1s 22s 22p 63s 23p 6) cores and core valence correlation correction added to the electrostatic Hamiltonian with Gaussian basis sets for both atoms. The core valence effects including core-polarization and core-valence correlation are taken into account by using an l-dependent core-polarization potential. The molecular orbitals have been derived from self-consistent field (SCF) calculation. The spectroscopic constants, dipole moments and vibrational levels of the lowest electronic states of the LiK molecule dissociating into K (4s, 4p, 5s, 3d, and 5p) + Li (2s, 2p, 3s, and 3p) in 1, 3Σ, 1, 3Π, and 1, 3Δ symmetries. Adiabatic results are also reported for 2Σ, 2Π, and 2Δ electronic states of the molecular ion LiK+ dissociating into Li (2s, 2p, 3s, and 3p) + K+ and Li+ + K (4s, 4p, 5s, 3d, and 5p). The comparison of the present results with those available in the literature shows a very good agreement in spectroscopic constants of some lowest states of the LiK and LiK+ molecules, especially with the available theoretical works. The existence of numerous avoided crossing between electronic states of 2Σ and 2Π symmetries is related to the charge transfer process between the two ionic systems Li+K and LiK+. 相似文献
11.
T. Royer D. Dowek J. C. Houver J. Pommier N. Andersen 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,10(1):45-57
Electron capture processes in the H+?Na(3s) and H+?Na(3p) collisions are experimentally investigated in the 0.3–3 keV energy range using a crossed beam experiment. The excited Na(3p) target is produced with a well-defined alignment using laser pumping. The time of flight technique enables the identification of all the H(n)+Na+ channels populated in the collision. Total cross section ratios σ3p (n=2)/σ3s (n=2),σ3p (n=3)/σ3s (n=2) and σ3s (n=3)/σ3s (n=2) for the production of H(n=2) and H(n=3) are measured in the H+?Na (3s) and H+?Na (3p) collisions. They reveal a strong dominance of the production of H(n=2) in the H+?Na(3p) collision, especially for energies below 1 keV. 相似文献
12.
We report in this paper, energy resonances of the 2s22p4 (1D2)ns,nd, 2s22p4(1S0) ns,nd and 2s2p5 (3P2)np series originating from both 2s22p5 2P1/2 metastable and 2s22p5 2P3/2 ground state of Ne+. Calculations are performed using the Screening Constant by Unit Nuclear Charge (SCUNC) method and high lying states up to n=75 are investigated. The results obtained in this work agree very well with Advanced Light Source experiments on Ne+ (Covington et al., 2002). The analysis of the present results is achieved by calculating the effective charge number in the framework of the SCUNC formalism and by evaluating the quantum defect from the standard quantum defect expansion formula. Both effective nuclear charge and quantum defect are almost constants up to n=75. 相似文献
13.
T. Brodzinski H. -D. Kronfeldt J. -R. Kropp R. Winkler 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1987,7(2):161-164
Nine transitions (ranging from 475 till 733 nm) between the excited configuration 3d 5 4s 5s and 3d 5 4s 4p of55Mn were investigated with computer supported interference spectroscopy. Thus the hyperfine structure (hfs) of the four 4s 5s and the twelve 4s 4p levels is now completely known from experiment. The hfs results are discussed with the effective operator technique and for 4s 4p the accuracy of the one-electron parametersa ik could be improved:a 3d 10 =?6.28(24),a 4s 10 =154.0(1.4),a 4p 01 =9.3(8),a 4p 12 =7.7(2.5) in mK. For the configuration 4s 5s — for which fine structure calculations are not yet available — the experimental hfs data prove a practically pureS-character. Besides the one-electron splitting parameters deduced:a 3d 10 =?6.5(5),a 4s 10 =182(3),a 5s 10 =24(3) in mK, permit to determine the degree of mixing between the twoe 6 S 5/2 andf 6 S 5/2 levels which amounts to about 3%. 相似文献
14.
B. A. Bushaw H. -J. Kluge J. Lantzsch R. Schwalbach J. Stenner H. Stevens K. Wendt K. Zimmer 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,28(4):275-281
The hyperfine spectra of the 5s4d 3 D 1-5s20f, 5s4d 3 D 2-5s23f, and 5s 4d 3 D 3-5s32f transitions of87Sr (I=9/2) have been measured by collinear fast beam laser spectroscopy. The structure in the upper configurations is highly perturbed by fine structure splitting that is of comparable size to the hyperfine interaction energy. These perturbations can be adequately treated with conventional matrix diagonalization methods, using the 5s-electron magnetic dipole interaction terma 5s and the unperturbed fine structure splittings as input parameters. Additionally, hyperfine constants for the lower 5s4d 3 D configurations, including theA- andB-factors and a separation of the individuals- andd-electron contributions to these factors, are derived. 相似文献
15.
J. Kwela Z. Konefal R. Drozdowski J. Heldt 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,9(3):215-218
The angular distribution of the electric-field-inducedE1 radiation is asymmetric with respect to the external electric field direction. Measurement of this asymmetry for the 5s4d 1 D 2 → 5s 2 1 S 0 transition in strontium permits the experimental determination of the 5s5p 1 P 1 → 5s4d1 D 2 decay rate. The result is:A(1 P 1 →1 D 2)=(4.37±0.93±0.66) × 103 s ?1. 相似文献
16.
W. Neu R. Neugart E. W. Otten G. Passler K. Wendt B. Fricke E. Arnold H. J. Kluge G. Ulm 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,11(2):105-111
The hyperfine structure and isotope shift of221–226Ra and212,214Ra have been measured in the ionic (Ra II) transition 7s 2 S 1/2–7p 2 P 3/2 (λ=381.4 nm). The method of on-line collinear fast-beam laser spectroscopy has been applied using frequency-doubling of cw dye laser radiation in an external ring cavity. The magnetic hyperfine fields are compared with semi-empirical and ab initio calculations. The analysis of the quadrupole splitting by the same method yields the following, improved values of spectroscopic quadrupole moments:Q s (221Ra)=1.978(7)b,Q s (223Ra)=1.254(3)b and the reanalyzed valuesQ s (209Ra)=0.40(2)b,Q s (211Ra)=0.48(2)b,Q s (227Ra)=1.58(3)b,Q s (229Ra)=3.09(4)b with an additional scaling uncertainty of ±5%. Furthermore, theJ-dependence of the isotope shift is analyzed in both Ra II transitions connecting the 7s 2 S 1/2 ground state with the first excited doublet 7p 2 P 1/2 and 7p 2 P 3/2. 相似文献
17.
We demonstrate the possibility of performing high resolution laser spectroscopy of iridium atoms produced by sputtering in a hollow cathode discharge. By resolving the hyperfine structure of ultraviolet transitions from the ground state, we measure the magnetic dipole and electric quadrupole constants of the 5d 7 6s 6p 6 G 11/2 and 5d 7 6s 6p 6 F 7/2 excited levels and we obtain accurate values for the isotope shifts. Iridium is also discussed as possibly providing reference spectra in the 243 nm region, close to the wavelength of the 1s–2s two-photon transition of hydrogen. 相似文献
18.
In the Eu I configuration 4f 7 6s6d the isotope shift (IS) and hyperfine-structure (hfs) of the termse 6 D ande 10 D were determined from fourteen transitions (4f 7 6s6d-4f 7 6s6p) with computer supported interference spectroscopy. From the IS of altogether nine levels of 4f 7 6s6d the crossed-second-order-parameterg 3(4f,6s)=?0.90(6)mK was evaluated. The ratiog 3/G 3=?4.4(3)·10?6 (G 3: Slater Integral of the fine structure) is of the same size as that from five other independent investigations and one theoretical value. The single electron hfs splitting constantsa 4f 10 =?1.9(3)mK,a 6s 10 =391(3)mK, anda 6d 12 =0.9(3)mK were also evaluated and are compared with those of other Eu 4f 7 6snl configurations. 相似文献
19.
J. Kwela 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1987,6(1):25-29
The angular distribution of the electric-field-inducedE1 radiation is asymmetric with respect to the electric field direction as a result of mixing of states of different parity. Measurement of this anisotropy in atomic calcium permits the experimental determination of the decay rate between the1 P and metastable1 D levels. We obtain the resultA(4s4p 1 P 1 0 ?5s4d 1 D 2)=(3.32±0.85±0.50)×103 s?1. 相似文献
20.
M. Voss W. Weiss B. Buchholz R. Winkler 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1986,1(2):151-156
By optical interference and VUV spectroscopy the doublet system of SbI 5p 26s was investigated, so that now the hyperfinestructure of all 8 levels of 5p 26s (A- andB-splitting constants) are known. From the analysis we receive a spin-orbit parameter ζ5p =3,538(57) cm?1 and from the hyperfine-analysis single electron splitting constantsa 5p 01 =52.4(4.6),a 5p 10 =?1.6(7.3),a 5p 12 =72.3(2.3),a 6s 10 =91.7(4.1),b 5p 02 =?49.6(1.1) andb 5p 11 =30.4(3.2) (all values in mK). For all calculations in the fs- and hfs-analysis the 5p 26s 2 D 3/2 has to be excluded (see discussion). With the figures given above the quadrupole moment121 Q(5p 26s)=?0.44(3) barn was obtained. It is in good agreement with the121 Q(5p 3). For the core-polarization by the 5p electron in the innerfieldns-shells (n=1, 2, 3, 4, 5) and the unpaired 6s electron a field of +500(300) kG was obtained. 相似文献