共查询到20条相似文献,搜索用时 15 毫秒
1.
S.M. Afzal S.G. Nakhate S.A. Ahmad 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1996,37(3):249-253
Isotope shift (IS) Δσ (142–150) have been measured in 92 spectral lines of Nd+ in the region 3290–3955 Å, employing recording Fabry-Perot spectrometer and highly enriched isotopic samples excited in a liquid-nitrogen cooled hollow cathode. Earlier IS measurement in UV region of Nd II spectrum is available for only a few lines, New classification has been made for several of the spectral lines studied presently. We have also revised the earlier suggested classification for some of the Nd II lines on the basis of observed isotope shifts. The transitions presently studied mostly involve high lying odd parity energy levels above 30,000 cm?1 having neither electronic configuration assignment nor term isotope shifts (ΔT) evaluated. The present study would thus enable to evaluate ΔT values of some of these high lying odd levels, which should be helpful in suggesting possible electronic configurations. 相似文献
2.
S.A. Ahmad A. Venugopalan G.D. Saksena 《Spectrochimica Acta Part B: Atomic Spectroscopy》1979,34(5):221-235
Isotope shift studies in the gadolinium spectra have been extended in the region 4140–4535 Å. Isotope shift Δσ(156–160) have been measured in 315 lines of the neutral and singly ionised galolinium atom using a recording Fabry—Perot Spectrometer and gadolinium samples enriched in 156Gd and 160Gd isotopes. Some of the Gd I lines studied involve transitions from newly identified high odd levels of 4f86s 6p, 4f75d 6s 7s and 4f75d3 configurations to low even levels of 4f86s2 and 4f76s26p configurations. Electronic configurations of the energy levels have been discussed on the basis of observed isotope shifts. In some cases assigned configurations have been revised and probable configurations have been suggested. 相似文献
3.
S.A. Ahmad I.J. Machado G.D. Saksena 《Spectrochimica Acta Part B: Atomic Spectroscopy》1980,35(4):215-224
Isotope shift △σ (172–176) have been measured in 172 lines of the first spectrum of ytterbium in the region 3900–6500 Å employing a recording Fabry—Perot spectrometer and highly enriched isotopes excited in liquid-air-cooled hollow cathodes. Out of the 172 lines studied, energy level classifications are available for 167 of them. Isotope shift △T (172–176) of 62 even and 59 odd energy levels of Yb I have been evaluated and their electronic configurations discussed. 相似文献
4.
Pushpa M. Rao S. A. Ahmad A. Venugopalan G. D. Saksena 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1990,15(3):211-220
Isotope shift ΔT (148–154) has been evaluated for twelve low-lying even and 89 odd parity levels of singly ionised samarium (Sm II) from the isotope shift (IS) studies in 182 spectral lines of Sm II in the 3890–4525 Å region. These studies were carried out on a recording Fabry-Perot spectrometer using eriched isotopes148Sm (96%) and154Sm (98%) excited in liquid nitrogen-cooled hollow-cathodes. Earlier data on isotope shifts are available for only eight lines in this region. It has been found that for a few spectral lines there are errors both in magnitudes and signs of isotope shifts, reported earlier. Most of the 89 odd parity levels of Sm II, for which ΔT values have been evaluated presently, have in literature either no electronic configuration assignments or only tentative assignments. We have suggested the leading configuration for most of these odd levels of Sm II on the basis of ΔT values evaluated in the present studies. 相似文献
5.
6.
S. M. Afzal A. Venugopalan S. A. Ahmad 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,41(2):95-100
Isotope shift Δσ(156Gd?160Gd) is reported in 70 spectral lines of neutral gadolinium atom (Gd I) in the 3290- 3920 Å region providing isotope shift data in UV lines of Gd I spectrum for the first time. The measurements were carried out on a photoelectric recording Fabry-Perot Spectrometer using highly enriched isotopic samples of gadolinium. Term isotope shifts ΔT(156Gd?160Gd) have been evaluated for 48 high lying even parity energy levels of Gd I using this data; new ΔT values have been obtained for 24 levels. Electronic configurations 4f75d6s6p, 4ff75df26p and 4f85d6s assigned earlier to these even levels have been either confirmed or configuration mixing pointed out in some of these levels. Probable assignment of 4f85d6s configuration to 8 even levels between 32 930 and 35 500 cm-1 have been confirmed. 相似文献
7.
《Spectrochimica Acta Part B: Atomic Spectroscopy》2005,60(1):33-40
Thirty-three spectral lines of chromium atom in the blue-violet region (425–465 nm) have been investigated with the method of laser-induced resonance fluorescence on an atomic beam. For all the lines, the isotope shifts for every pair of chromium isotopes have been determined. The lines can be divided into six groups, according to the configuration of the upper and lower levels. Electronic factors of the field shift and the specific mass shift (Fik and MikSMS, respectively) have been evaluated and the values for each pure configuration involved have been determined. Comparison of the values Fik and MikSMS to the ab initio calculations results has been performed. The presence of crossed second order (CSO) effects has been observed. 相似文献
8.
B. Furmann D. Stefańska A. Krzykowski A. Jarosz A. Kajoch 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1996,37(4):289-294
Isotope shifts in ten optical transitions of Ti atom have been investigated by using laser induced fluorescence on a collimated atomic beam. From the isotope shifts data, using a combined analysis with muonic atom data, specific mass shifts and field shifts have been determined and corrected values of changes of the mean square nuclear charge radii have been obtained. 相似文献
9.
Isotope shifts ΔT (142–144) have been evaluated for odd and even energy levels of the singly ionised neodymium atom from the measurements carried out in 168 spectral lines in the 3930–5820 Å region, employing a recording Fabry-Perot spectrometer and highly enriched isotopes excited in liquid-air cooled hollow cathodes. The electronic configurations 4f35d6s, 4f35d6p and 4f46p could be assigned to some of the energy levels on the basis of the present study. 相似文献
10.
Pushpa M. Rao A. Venugopalan S.A. Ahmad G.D. Saksena 《Spectrochimica Acta Part B: Atomic Spectroscopy》1985,40(8):1059-1066
Isotope shifts ΔT (170-166) have been evaluated for 54 even and 94 odd energy levels covering almost all the known configurations of the neutral erbium. These ΔT values have been derived from the isotope shift measurements carried out in 159 lines in the region 3900–4605 A using a Fabry-Perot spectrometer and liquid-air-cooled hollow cathode source with highly enriched 170Er and 166Er isotopic samples. Electronic configurations assigned to energy levels of Er I by earlier workers have been mostly confirmed and in few cases revisions have been suggested on the basis of observed ΔT values. Probable configurations have been also suggested for unassigned levels of Er I, and a large number of even levels could be assigned to 4f11 5d 6s 6p configuration. 相似文献
11.
E. M. Azaroual P. Luc R. Vetter 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1992,24(2):161-164
The use of an effusive beam of titanium atoms crossed with a CW single-mode tunable dye laser has allowed the high-resolution, Doppler-free study of the isotope shifts between50Ti,48Ti and46Ti, for seven 3d
2 4s
2 a3
F
J
3d
2 4s 4p z
5
D
J
, visible transitions of Ti I. The measurements show without ambiguity the existence of a non-negligible field shift. Using the values of the nuclear radii of titanium (coming from muonic X-ray measurements), it is possible to determine the respective values of the field and mass shifts. 相似文献
12.
The isotope shift in the proton magnetic resonance of deuteromethanes has been examined. By the use of Pople's formula for the chemical shift, it has been shown that the effect is due to vibronic coupling from the bending modes S4. The chemical shift was evaluated under the assumption that the hydrogen population is linearly dependent on the 2S character of the bonded carbon hybrid. Satisfactory agreement between theoretical and experimental results was obtained. 相似文献
13.
M. Anselment S. Chongkum K. Bekk S. Göring A. Hanser G. Meisel H. Rebel 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1986,3(4):421-422
We give data of the isotope shift for the strontium isotopes from A=80 to A=90. They are found to be inconsistent with data from another optical transition. Possible reasons for the discrepancy are discussed. 相似文献
14.
P. Luc R. Vetter C. Bauche-Arnoult J. Bauche 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1994,31(3):145-148
High accuracy measurements of hyperfine structure due to47Ti and49Ti in the 3d 2 4s 2 a 3 F 2?3d 2 4s4p z 5 D 1 absorption line at σ=18482.772 cm?1 have been performed by use of a Doppler-free experiment, where a beam of titanium atoms is crossed by a CW single mode tunable dye laser. They have allowed for the determination of isotope shifts between46Ti,47Ti,48Ti,49Ti and50Ti. By use of accurate values of mean square nuclear charge radii for the even isotopes, it has been possible to separate mass shifts from field shifts and to determine accurate values for the mean square nuclear charge radii of47Ti and49Ti. The field shift presents a marked odd-even staggering. 相似文献
15.
V. Lodwig H. H. Bukow H. v. Buttlar 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,9(2):177-186
A detailed study of the N II-N III spectra after foil-excitation of fast nitrogen ions has covered the wavelength range 40 nm to 125 nm. Among a total of 366 lines recorded, all N II and N III lines given in the literature have been reproduced. For 130 lines not previously reported a charge state determination has been done, and for 5 lines new identifications are proposed. The analysis performed on low resolution spectra has been corroborated by high resolution data obtained at another laboratory. 相似文献
16.
A. Ajdarzadeh Oskouei O. Brm A. Cannizzo F. van Mourik A. Tortschanoff M. Chergui 《Chemical physics》2008,350(1-3):104
We present photon echo peak shift and femtosecond fluorescence up-conversion studies of non-polar solvation dynamics of a simple non-polar dye p-terphenyl in ethanol and cyclohexane, using excitation in the UV range at 290 nm. The UV fluorescence up-conversion experiments were combined with a polychromatic detection and the results highlight the high sensitivity of this approach to fully characterize the excited state dynamics of the dye. We also demonstrate the feasibility of UV photon echo and transient grating and its sensitivity for the detection of non-polar solvation dynamics by measuring the frequency correlation function of the dye in the ground state. While solvation dynamics in the picosecond regime is observed in ethanol, electronic coherence dephasing occurs on timescales faster than 100 fs in ethanol as well as in the non-polar solvent cyclohexane. 相似文献
17.
de Petris G Cartoni A Rosi M Troiani A Angelini G Ursini O 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(24):6411-6421
A hitherto unknown, atmospherically relevant, isotope-exchange reaction was studied in ionised gaseous mixtures containing carbon dioxide and monoxide. The mechanism of the O exchange, proceeding over a double-minimum potential-energy surface, was positively established by mass spectrometric and theoretical methods that also allowed the identification and characterisation of the C2O3+ intermediate. The increase of internal energy displaces the observed reactivity towards an endothermic reaction path that involves only CO2 and represents an indirect route to the dissociation of carbon dioxide. 相似文献
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19.
Ch. Bourauel W. Rupprecht S. Büttgenbach 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1987,7(2):129-132
Isotope shifts in 17 transitions of ZrI have been measured by Doppler-free laser polarization spectroscopy in a hollow cathode discharge. The results were combined with other known isotope shift data of ZrI and tested for consistency in a multidimensional King plot. By including values ofδ〈r 2〉 deduced from optical isotope shifts mass and field shifts were separated, and improved values ofδ〈r 2〉 could be determined from the King plot. The results for the isotope pairs A, A′ are as follows; 90, 92: 0.244(43) fm2; 92, 94: 0.176(20) fm2; 94, 96: 0.126(23) fm2. 相似文献
20.
W. Neu G. Passler G. Sawatzky R. Winkler H. -J. Kluge 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1987,7(2):193-201
Isotope shift (IS) and hyperfine structure (hfs) measurements have been performed on seven lines of the platinum I spectrum with interference as well as laser fluorescence spectroscopy. In the latter case a frequency-doubled single-mode cw dye laser was applied. The IS of190Pt with a natural abundance of only 0.01% was determined to beδν 190, 192=?38.65(8) mK in theλ306.47 nm transition. The IS parameters and the effective hfs integrals in the configuration (5d+6s)10 were determined in intermediate coupling by a least squares fit of the IS and hfs data with eigenvectors obtained from the platinum fine structure (fs). The results are compared with theoretical values and yield improvedδ〈r 2〉 data. 相似文献