Optics and Spectroscopy, Vol. 93, No. 6, 2002, pp. 826–832. Translated from Optika i Spektroskopiya, Vol. 93, No. 6, 2002, pp. 896–903. Original Russian Text Copyright © 2002 by Churilov.
ATOMIC SPECTROSCOPY
Analysis of the Spectrum of the Zn-Like Kr VII Ion: Highly Excited 4p4d and 4p5s Configurations S. S. Churilov Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow oblast, 142190 Russia Received May 7, 2002
Abstract—The spectrum of the Zn-like Kr VII ion, excited in a capillary discharge and recorded with a high resolution in the wavelength range of 300–1000 Å, was studied. Previously performed identification of the transitions from the levels of the 4s4f, 4s5s, 4s5p, and 4s5d configurations is confirmed and extended, and the energies of these levels are specified. The (4p2 + 4s4d) – 4p4d and (4p2 + 4s5s) – 4p5s transitions are identified for the first time, and the energies of all the levels of the 4p4d and 4p5s configurations are determined. The results of the analysis performed are confirmed by semiempirical calculations in terms of the Hartree–Fock method. These results are also shown to conform to the experimental data obtained for lighter ions of the Zn I isoelectronic sequence. © 2002 MAIK “Nauka/Interperiodica”.
INTRODUCTION The spectra of the Zn-like ions with the ground configuration 3d104s2 are of considerable interest for the development of methods of theoretical calculations of the atomic structures and for the diagnostics of hightemperature plasmas. In addition, multiply charged ions of inert gases can serve as a convenient object for the measurement of the lifetimes of electronic states in experiments with ion beams. In this connection, the spectrum of the Zn-like Kr VII ion has been intensively studied by many authors with the use of different excitation sources [1–9]. A critical compilation of the experimental data on the spectrum of the Kr VII ion was carried out in [10], in which a list of identified spectral lines and measured energies of the levels of the 4s4p, 4p2, 4s4d, 4s4f (except for the 1F3 level), 4s5s, 4s5p, and 4s5d configurations is reported. However, the transitions from highly excited 4s5s 1S0, 4s4f, 4s5p, and 4s5d levels of the Kr VII ion were studied mainly by using low-resolution spectrometers [5, 8, 9]. Since the energies of these levels were determined with an error of 40–100 cm–1, the results obtained are somewhat ambiguous. In particular, the wavelengths of some identified lines are inconsistent with the measured energies of the corresponding levels [10], and a number of rather strong transitions in the spectrum of the Kr VII ion have yet to be identified. Furthermore, investigations of the lighter Zn-like As IV, Se V, and Br VI ions [11, 12] revealed a strong interaction of the 4s4f and 4s5p levels with the 4p4d configuration. The latter configuration in the energy structure of the Kr VII ion has not been studied at all, although it also may significantly affect neighboring configurations. The aim of this paper was to perform a critical analysis, more accurate determination, and extension of known data on the spectrum of the Zn-like Kr VII ion, as well as to study
the highly excited 4p4d and 4p5s configurations of this ion. METHODS OF DETECTION AND CALCULATIONS OF SPECTRA The spectra of Kr ions were excited in a fast capillary discharge by using an inductive energy storage. The design and principle of operation of the discharge source were described in detail in [13]. The operating voltage was of 35 kV for a highest discharge current in the range of 80–100 kA and for a current-pulse width of 200 ns. The discharge was initiated in a ceramic (Al2O3) capillary 40 mm long with an inner diameter of 2 mm. The initial Kr pressure in the capillary was in the range of 0.1–0.3 Torr. Spectra were recorded in the wavelength range of 300–1000 Å, using a normal incidence VUV spectrograph with a 1200 1 / mm diffraction grating with a radius of 6.65 m. The reciprocal linear dispersion of the spectrograph was 1.25 Å/mm. The spectral resolution was limited mainly by the Doppler effect in the source and varied from 7000 to 10000 for wavelengths ranging between 300–1000 Å. The spectra were photographed on Kodak SWR plates and measured by using an automated microphotometer-comparator. The wavelengths of known lines of Kr (VI–VIII) ions [10] and impurity O (IV, V) and Al (V–VII) ions were used as reference wavelengths [14]. The average measurement accuracy for the wavelengths of unperturbed lines was ± 0.007 Å. The line intensities were determined by measuring the photographic densities at the line centers with regard to the characteristic curve of the photographic emulsion. The intensity of the strongest spectral line was assumed to be 100. The spectrum of the Kr VII ion was calculated by the Hartree–Fock method employing the Cowan software package [15]. The calculations covered the even
0030-400X/02/9306-0826$22.00 © 2002 MAIK “Nauka/Interperiodica”
ANALYSIS OF THE SPECTRUM OF THE Zn-LIKE Kr VII ION
configurations 4sns (n = 4–6), 4p2, 4snd (n = 4, 5), 4d2, 4p5p, 4p4f, and 3d94s24d and the odd configurations 4snp (n = 4–6), 4snf (n = 4, 5), 4p4d, 4p5s, and 3d94s24p. The highly excited 4p5p, 4p4f, 4d2, 3d94s24p, and 3d94s24d configurations were taken into account due to the large integrals of their interaction with the lower configurations. In the calculations of the studied configurations, we used energy parameters that were semiempirically extrapolated along the As IV–Br VI sequence [11, 12]. To increase the extrapolation accuracy, we recalculated the spectra of the As IV, Se V, and Br VI ions using the same set of configurations. For the configurations that were not extrapolated along this sequence, we used the Hartree–Fock (HF) values of the average energies and spin–orbit parameters. The Slater parameters of these configurations, as well as the parameters of interaction between the configurations, were fixed at a level of 0.85 of their HF values. RESULTS AND DISCUSSION The recorded Kr spectra contain mainly the lines of the ions in the range from Kr VI to Kr IX. The spectra of the Kr VI and Kr VIII ions in the wavelength range of 300–1000 Å have been studied fairly thoroughly [10]. The 4–4 transitions in the Ni-like Kr IX ion, which also lie in this range, were identified concurrently with the analysis of the spectrum of the Kr VII ion, and the results of their analysis will be published elsewhere. Thus, only a relatively small number of the lines in the recorded spectra remained to be identified, which significantly facilitated the analysis of the spectrum of the Kr VII ion. The identification of the lines of the Kr VII ion was carried out by means of the IDEN program, developed for identification of complex spectra [16, 17]. The results are summarized in Table 1. This table contains the wavelengths (λ), intensities (I), and wave numbers (ν) of the identified lines, as well as the calculated transition probabilities (gA) and deviations ∆λ of the measured line wavelengths from the corresponding values calculated from the energies of the levels that are presented in Table 2. Table 1 contains the data for all the transitions observed in the spectrum of the Kr VII ion, including those identified previously in [6–9] (see the references in the last column). As in [6–9], the wavelengths of all the lines are given for a vacuum. For the previously identified lines located outside the wavelength range of this study (λ < 300 Å and λ > 1000 Å), the table lists the errors of the wavelength measurement, that were indicated in the corresponding publications. In the range of 300–1000 Å, we failed to find only one previously identified line, due to a very weak 4p2 2P2–4s5p 3P1 transition (λ = 487.4 ± 0.8 Å, [8]). On the basis of the new spectral data, we confirmed the identification of 61 lines from the 62 reported in [10]. For all the lines, the deviations ∆λ do not exceed the corresponding errors of the wavelength measureOPTICS AND SPECTROSCOPY
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ment. The only exception is the line at 845.5 ± 0.5 Å, attributed to the 4s4d 1D2–4s5p 1P1 transition [8, 9]. For this line, the deviation from the calculated wavelength amounts to –1.6 Å. This deviation is most likely due to insufficient resolution of the instruments used in [8, 9]. As can be seen from the spectrogram reported in [8], the at line 845.5 Å has a halfwidth of about 5 Å and appears to be blended by other lines. We detected three spectral lines in the range of 843–848 Å. One of these lines, at 847.129 Å, was attributed to the 4s4d 1D2– 4s5p 1P1 transition, because, in accordance with the Ritz principle, it correlates with other identified lines caused by transitions from the 4s5p 1P1 level. The wavelengths of the previously identified lines attributed to the (4p2 + 4s4d)–(4s4f + 4s5p) transitions were refined, and several lines were identified for the first time. In particular, we identified the lines related to the 4p2 1D2–4s4f 1F3 and 4s4d 1D2–4s4 f 1F3 transitions, which made it possible to determine the energy of the 4s4f 1F3 level. In total, 37 spectral lines of the Kr VII ion were identified in this study for the first time, and 24 of these lines were attributed to the (4p2 + 4s4d) – 4p4d transitions. It can be seen from Table 1 that these transitions have fairly high probabilities and lie in the same spectral region as the (4p2 + 4s4d) – (4s4f + 4s5p) transitions. Several lines assigned to the 4p2–4p5s transitions and located in the range of 310–330 Å were also identified. The energies of most of the 4p5s levels were determined from only a single line. Nevertheless, we consider our identification to be unambiguous, because no other lines were found in the relevant spectral regions. In addition, the identification of the 4p2 3P2– 4p5s 3P2 transition (λ = 325.812 Å) is confirmed by the observation of the 4s5s 3S1−4p5s 3P2 transition (λ = 639.076 Å). The measured energies of the levels are listed in Table 2. This table also contains the compositions of the wave functions, expressed as a sum of contributions from the terms of the L–S coupling, and the deviations ∆E = Eexptl – Ese, where Eexptl and Ese are the experimentally measured and semiempirically calculated energies, respectively. It can be seen that effects of mixing of the 4s4f, 4s5p, and 4p4d states in the Kr VII ions take place as well, especially for the term 1F3. It is the effects of mixing of states that are responsible for the occurrence of strong lines related to the two-electron 4p2–4s4f and 4p2–4s5p transitions in the Kr VII ion (Table 1). The measured energy of the 4s4f 1F3 level (559998 cm–1) is close to the value of 559500 cm–1 predicted in [9]. In accordance with the calculations, the energy of this level depends on the relative position of levels of the 4p4d configuration. Therefore, a reliable determination of the energy of the 4s4f 1F3 level became possible only after determining the energetic structure of the 4p4d configuration.
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Table 1. Identified transitions in the spectrum of the Zn-like Kr VII ion Transition
gA × 10–8, s–1
I*
λ, Å
∆λ, Å
ν, cm–1
**
1
2
3
4
5
6
7
200.9 ± 0.5 221.4 ± 0.5 311.270 311.475 313.925 320.424 325.360 325.812 326.759 356.785 361.908 385.538 388.234 429.953 434.171 435.027 443.406 444.561 445.025 445.315 446.697 447.609 449.290 453.955 454.403 458.125 459.168 460.301 460.428 462.630 468.388 474.537 477.770 479.283 480.227 480.916 482.212 487.4 ± 0.8 500.165 501.343 508.385 553.952 554.425 555.270 555.833 556.607 556.855 557.427 558.250
–0.104 0.434 –0.009 0.000 –0.002 0.000 0.000 –0.004 0.000 0.001 0.000 0.006 0.010 –0.003 –0.002 0.001 0.001 0.000 –0.007 0.000 –0.001 0.008 –0.004 0.000 0.000 –0.004 0.004 –0.003 –0.001 0.005 –0.009 –0.001 0.010 –0.007 0.005 0.004 0.010 –0.364 0.010 –0.008 –0.001 0.000 –0.009 –0.005 0.006 0.000 0.009 0.001 –0.001
497760 451670 321264 321053 318547 312086 307352 306925 306036 280281 276313 259378 257576 232584 230324 229871 225527 224941 224706 224560 223865 223400 222573 220286 220069 218281 217785 217249 217189 216155 213498 210732 209306 208645 208235 207936 207378 205170 199934 199464 196701 180521 180367 180093 179910 179660 179580 179396 179131
[8] [8] [7]
4s2 1S
1 0–4s5p P1 3 4s4p P2–4s5d3D3 4s4p 3P0–4s5p3S1 4p2 1D2–4p5s1P1 4s4p 3P1–4s5s3S1 4s4p 3P2–4s5s3S1 4p2 1D2–4p5s3P1 4p2 3P2–4p5s3P2 4p2 3P1–4p5s3P0 4p2 1D2–4s4f1F3 4s4p 1P1–4s5s1S0 4s4p 3P1–4s4d1D2 4p2 3P0–4p4d1P1 4s4p 3P0–4s4d3D1 4s4p 3P1–4s4d3D2 4s4p 3P1–4s4d3D1 4p2 3P1–4p4d3P1 4p2 3P1–4p4d3P0 4p2 3P0–4p4d3D1 4s4p 3P2–4s4d3D3 4s4p 3P2–4s4d3D2 4s4p 3P2–4s4d3D1 4p2 3P0–4s5p1P1 4p2 1D2–4p4d1F3 4p2 3P1–4p4d3P2 4p2 3P0–4s5p3P1 4p2 1D2–4s5p1P1 4p2 3P2–4p4d3D3 4p2 3P2–4p4d3D2 4p2 3P1–4s5p3P2 4p2 1D2–4s5p3P1 4p2 1S0–4p4d1P1 4p2 3P2–4s5p1P1 4s4p 1P1–4s4d1D2 4p2 3P1–4p4d1D2 4p2 1D2–4p4d1D2 4p2 3P2–4s5p3P2 4p2 3P2–4s5p3P1 4p2 1D2–4p4d3F3 4p2 3P2–4p4d1D2 4p2 1D2–4p4d3F2 4s4d 1D2–4s4f1F3 4s4d 3D1–4s4f3F2 4s4d 3D2–4s4f3F3 4s4d 3D2–4s4f3F2 4s4d 3D3–4s4f3F4 4s4p 1P1–4s4d3D2 4s4d 3D3–4s4f3F3 4s4p 1P1–4s4d3D1
128 7 90 360 262 416 153 408 140 282 194 10 5 406 858 284 467 196 603 1503 267 18 130 1665 956 10 39 1954 794 61 10 682 37 1565 70 620 42 3 38 78 44 2455 939 1399 161 2020 1 158 0.7
3 7 5 7 5 7 5 7 5 15 10 40 50m 35 7 8 9 65 40 17m 15 35 15 3 10 12 10 10 9 13 10m 50 8 20 6 6 5 10 45 40 65bl 22 55 5 30 10
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[7] [7]
[8] [7] [7] [6] [6]
[6] [6] [6]
[8] [8]
[7]
[6]
[7] [8]
[9] [9] [9] [6] [9] [6]
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Table 1. (Contd.) 1 4p2 1S0–4p4d3D1 4p2 1S0–4s5p3P1 4s2 1S0–4s4p1P1 4s4p 3P1–4p2 3P2 4s4p 3P0–4p2 3P1 4s4p 3P2–4p2 3P2 4s4p 3P1–4p2 1D2 4s4p 3P1–4p2 3P1 4s5s 3S1–4p5s3P2 4s4d 3D1–4p4d3P1 4s4d 3D2–4p4d3D2 4s4p 3P1–4p2 3P0 4s4d 3D3–4p4d3D3 4s4p 3P2–4p2 1D2 4s4d 1D2–4p4d1P1 4s4p 3P2–4p2 3P1 4s4p 1P1–4p2 1S0 4s4d 3D2–4p4d3D1 4s4d 3D3–4p4d3P2 4s4d 3D1–4s5p3P2 4s4d 3D2–4s5p3P2 4s4d 3D3–4s5p3P2 4s4d 3D1–4s5p3P1 4s4d 3D1–4s5p3P0 4s4d 3D2–4s5p3P1 4s4d 3D3–4p4d3F4 4s4d 3D2–4p4d3F3 4s4d 3D3–4p4d3F3 4s2 1S0–4s4p3P1 4s4d 1D2–4s5p1P1 4s4p 1P1–4p2 3P2 4s4p 1P1–4p2 1D2 4s4p 1P1–4p2 3P1 4s4p 1P1–4p2 3P0 4s5p 3P0–4s5d 3D1 4s5p 1P1–4s5d 1D2 4s5p 3P1–4s5d 3D2 4s5p 3P1–4s5d 3D1 4s5p 3P2–4s5d 3D3 4s5p 3P2–4s5d 3D2 4s5s 3S1–4s5p 3P2 4s5s 3S1–4s5p 3P1 4s5s 3S1–4s5p 3P0 4s5s 1S0–4s5p 1P1 4s4f 3F2–4s5d 3D3 4s4f 3F3–4s5d 3D3 4s4f 3F4–4s5d 3D3 4s4f 3F3–4s5d 3D2 4s4f 3F2–4s5d 3D1
2 3 0.5 346 102 484 306 47 81 274 139 217 100 270 96 130 121 113 138 323 3 23 67 23 30 55 79 50 18 0.6 78 25 48 0.2 0.3 63 122 141 42 221 35 38 22 8 12 0.1 2 22 13 11
3 10 10 80 50 55 70 53 60 7 6 8 40 20m 55 10 50 45 10 35m 3 4 8 5 10 13 16 9 7 15 12 10 30 3 5
10
4 562.262 583.335 585.357 594.890 617.158 618.649 626.482 627.657 639.076 645.250 645.310 645.842 647.970 652.896 653.432 654.168 662.475 670.169 673.975 686.761 688.915 692.231 698.121 700.270 700.330 749.467 773.771 777.955 832.680 847.279 852.100 918.440 920.970 960.640 1166.6 ± 0.2 1168.8 ± 0.2 1169.3 ± 0.2 1172.8 ± 0.2 1197.1 ± 0.2 1202.7 ± 0.2 1756.36 ± 0.01 1832.5 ± 0.5 1847.5 ± 0.5 1985.5 ± 0.5 2050.5 ± 0.5 2057.5 ± 0.5 2069.0 ± 0.5 2074.0 ± 0.5 2077.0 ± 0.5
5 –0.007 –0.007 –0.003 –0.001 0.000 –0.010 –0.002 –0.003 0.000 –0.003 –0.001 0.002 0.000 –0.003 0.000 –0.009 –0.001 0.004 –0.002 –0.010 0.006 0.008 0.011 –0.005 0.011 –0.001 –0.007 –0.007 –0.006 0.008 0.006 0.006 0.007 –0.002 –0.084 0.002 –0.072 0.055 –0.003 0.069 0.002 0.025 0.027 –0.400 0.480 –0.071 0.092 0.043 0.157
6 177853 171428 170836 168098 162033 161643 159621 159323 156476 154979 154964 154837 154328 153164 153038 152866 150949 149216 148373 145611 145156 144460 143242 142802 142790 133428 129237 128542 120094 118025 117357 108880 108581 104097 85719 85558 85521 85266 83535 83146 56936 54570 54127 50365 48769 48603 48336 48216 48146
* bl and m denote blending by the line of the O IV ion and partial masking by the neighboring line, respectively. ** Study in which this transition was identified for the first time. OPTICS AND SPECTROSCOPY
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[1] [6] [6] [1] [6] [6]
[6] [6] [6] [7]
[7] [7] [7] [9] [9] [9]
[6] [6] [6] [6] [6] [9] [9] [9] [9] [9] [9] [7] [9] [9] [9] [9] [9] [9] [9] [9]
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Table 2. Energies (cm–1) of the levels of the Zn-like Kr VII ion Eexptl , cm–1
ESE , cm–1
∆E, cm–1
J
Composition of the wave function of the level
117384 120095 126553 170835 274932 279417 279716 288193 321784 349966 350418 351113 379477 438639 447148 492767 493210 495575 497503 476417 479654 484541 487654 499635 499486 500002 504358 504944 505382 505441 532515 530330 530509 530773 559998 578480 578726 579110 583061 585453 587068 595115 600769
117395 120081 126556 170835 274903 279455 279725 288173 321785 349967 350416 351114 379477 438639 447148 492723 493258 495538 497525 476251 479783 484574 487645 499524 499763 499993 504353 504852 505303 505482 532515 530269 530501 530841 559997 578478 578729 579109 583061 585446 587077 595115 600768
–11 14 –3 0 29 –38 –9 20 –1 –1 2 –1 0 0 0 44 –48 37 –22 166 –129 –33 9 111 –277 9 5 92 79 –41 0 61 8 –68 1 2 –3 1 0 7 –9 0 1
0 1 2 1 0 1 2 2 0 1 2 3 2 1 0 0 1 2 1 2 3 4 2 1 2 3 0 1 2 3 1 2 3 4 3 1 2 3 2 0 1 2 1
100% 4s4p 3P 99% 4s4p 3P + 1% 4s4p 1P 100% 4s4p 3P 97% 4s4p 1P + 2% 4p4d 1P + 1% 4s4p 3P 96% 4p2 3P + 3% 4p2 1S 100% 4p2 3P 59% 4p2 1D + 32% 4p2 3P + 9% 4s4d 1D 67% 4p2 3P + 27% 4p2 1D + 5% 4s4d 1D 94% 4p2 1S + 3% 4p2 3P + 2% 4s2 1S 100% 4s4d 3D 100% 4s4d 3D 100% 4s4d 3D 85% 4s4d 1D + 13% 4p2 1D + 1% 4p4f 1D 99% 4s5s 3S + 1% 4p5p 3S 99% 4s5s 1S + 1% 4p5p 1S 97% 4s5p 3P + 3% 4p4d 3P 87% 4s5p 3P + 8% 4s5p 1P + 4% 4p4d 3P 83% 4s5p 3P + 12% 4p4d 3P + 3% 4p4d 1D 70% 4s5p 1P + 13% 4p4d 3D + 9% 4p4d 3P 87% 4p4d 3F + 6% 4p4d 1D + 6% 4s4f 3F 90% 4p4d 3F + 7% 4s4f 3F + 1% 4p4d 3D 91% 4p4d 3F + 9% 4s4f 3F 85% 4p4d 1D + 7% 4p4d 3P + 5% 4p4d 3F 55% 4p4d 3D + 19% 4p4d 3P + 17% 4s5p 1P 43% 4p4d 3P + 36% 4p4d 3D + 14% 4s5p 3P 47% 4p4d 1F + 40% 4s4f 1F + 10% 4p4d 3D 96% 4p4d 3P + 3% 4s5p 3P 66% 4p4d 3P + 31% 4p4d 3D + 2% 4s5p 3P 60% 4p4d 3D + 37% 4p4d 3P + 2% 4s5p 3P 89% 4p4d 3D + 6% 4s4f 1F + 5% 4p4d 1F 94% 4p4d 1P + 2% 4s4p 1P + 1% 4p4d 3D 93% 4s4f 3F + 7% 4p4d 3F 92% 4s4f 3F + 8% 4p4d 3F 91% 4s4f 3F + 9% 4p4d 3F 53% 4s4f 1F + 45% 4p4d 1F + 1% 4s5f 1F 98% 4s5d 3D + 2% 4p5p 3D 98% 4s5d 3D + 2% 4p5p 3D 99% 4s5d 3D + 1% 4p5p 3D 96% 4s5d 1D + 4% 4p5p 1D 99% 4p5s 3P + 1% 4s5p 3P 88% 4p5s 3P + 11% 4p5s 1P 99% 4p5s 3P 82% 4p5s 1P + 12% 4p5s 3P + 3% 4s6p 1P
* [6] [6] [6] [1] [6] [6] [6] [6] [7] [6] [6] [6] [6] [7] [8] [8] [8] [7] [8]
[9] [9] [9] [9] [9] [9] [9]
* Study in which the energy of the level was determined for the first time. OPTICS AND SPECTROSCOPY
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Table 3. Semiempirical (SE) and Hartree–Fock (HF) energy parameters and their ratios (SE / HF) for the Zn-like Kr VII ion SE, cm–1
Parameter Even configurations Eav(4s2) Eav(4p2) F2(4p, 4p) α(4p) ζ(4p) Eav(4s4d) ζ(4d) G2(4s, 4d) Eav(4s5s) G0(4s, 5s) Eav(4s5d) ζ(5d) G2(4s, 5d) Eav(4s6s) Eav(4p5p) Eav(4p4f) R1(4s, 4s; 4p, 4p) R1(4p, 4p; 4s, 4d) R1(4p, 4p; 4s, 5d) R2(4p, 4p; 4p, 4f) R1(4s, 4d; 4p, 4f) R3(4s, 4d; 4f, 4p) R1(4s, 5d; 4p, 5p) Standard deviation Odd configurations Eav(4s4p) ζ(4p) G1(4s, 4p) Eav(4s5p) ζ(5p) G1(4s, 5p) Eav(4p4d) ζ(4p) ζ(4d) F2(4p, 4d) G1(4p, 4d) G3(4p, 4d) Eav(4s4f) ζ(4f) G3(4s, 4f) Eav(4p5s) ζ(4p) G1(4p, 5s) Eav(4s6p) Eav(4s5f) Eav(4s6f)
HF, cm–1
9603 290846 60819 49 6026 356523 466 46223 442737 5065 581207 195 13975 616821 644229 674062 79309 69940 25262 42832 56385 30577 28966 31
(31) (18) (94) (13) (19) (17) (17) (105) (24) (22) (16) (17) (94)
137756 6129 79770 497088 2158 7933 499967 6003 413 42809 52678 32848 528830 9 25200 592972 6482 9261 643301 655533 724805
(69) (112) (239) (87) (120) (333) (42) (98)
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(353) (223) (308) (81) (825) (68) (101) (299)
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SE/HF experiment
extrapolation
9616 290451 70350 – 5212 355339 406 54795 441523 6295 580545 176 11159 616821 644229 674062 93305 82282 25262 42832 66335 35973 34078
0.9985 1.0015 0.864 – 1.156 1.003 1.148 0.843 1.003 0.805 1.001 1.108 1.252 1.000 1.000 1.000 0.850 0.850 0.850 0.850 0.850 0.850 0.850
0.998 1.002 0.880 35 1.160 1.002 1.150 0.850 1.002 0.800 1.002 1.100 1.000
136670 5228 93434 496848 1876 9624 499367 5318 413 60861 75419 47261 527447 9 27355 590619 5520 8999 643301 655533 724805
1.008 1.172 0.854 1.0005 1.150 0.824 1.001 1.129 1.000 0.703 0.698 0.695 1.0025 1.000 0.921 1.004 1.174 1.029 1.000 1.000 1.000
1.008 1.160 0.850 1.000 1.000 0.820 1.002 1.100 1.000 0.700 0.700 0.700 1.002 1.000 0.850 1.003 1.150 1.100
2002
0.850 0.850 0.850 0.850 0.850 0.850 0.850
832
CHURILOV
Table 3. (Contd.) Parameter R1(4s, 4p; 4s, 5p) R1(4s, 5p; 4p, 5s) R1(4s, 5p; 4p, 4d) R2(4s, 5p; 4d, 4p) R1(4p, 4d; 4s, 4f) R2(4p, 4d; 4f, 4s) Standard deviation
SE, cm–1 17951 37533 71444 53824 56634 38409 123
(218) (164) (173) (117)
The energies of the 4s4p, 4p2, and 4s4d levels, measured in this study with an error of 3–5 cm–1, coincide within the same error with the corresponding values reported in [6, 7]. The estimated error for the energy measurements of the 4s4f, 4s5s, 4s5p, 4s5d, and 4p4d levels is somewhat larger (about 8–10 cm–1). The energies of most triplet levels of these configurations are lower by 40–50 cm–1 than the energies of these levels reported in [9], which is within the experimental error indicated in [9]. It should be noted that the refined energy values eliminate the discrepancy between the wavelengths of the 4s5s 3S1–4s5p 3P1, 0 transitions (1832.5 and 1847.5 Å, respectively) earlier noted in [10]. On the average, the energies of the singlet levels 4s5s 1S0, 4s5p 1P1, and 4s5d 1D2 differ from the previously reported values by –250 cm–1. This difference is caused by the change in the wavelength of the 4s4d1D2– 4s5p 1P1 transition, discussed above. Table 3 contains the semiempirical (SE) and HF parameters of the studied configurations of Kr VII, as well as their ratios. This table also contains the most important parameters of interaction between the configurations, fixed at a level of 0.85 of their HF values, except for the parameters of interaction between the 4s5p–4p4d and 4s4df–4p4d configurations, which were varied so that the ratios of these parameters to their HF values remained constant. The deviations of the varied parameters during iterations are given in parentheses. The last column of Table 3 shows the SE / HF ratios for the parameters of the Kr VII ion, derived from the extrapolation of these ratios along the sequence of the As IV, Se V, and Br VI ions. We should note that some extrapolated SE / HF ratios listed in Table 3 differ from the corresponding ratios obtained in [11, 12]. This is associated with the fact that 4p5p, 4p4f, 4d2, 3d94s24p, and 3d94s24d configurations, which interact with the configurations understudy and thus affect their semiempirically calculated parameters, were taken into account in the calculations. It can be seen from Table 3 that the measured and extrapolated parameters are in good agreement. This fact, as well as the high accuracy of the semiempirical description of the measured ener-
HF, cm–1 17951 37533 82859 62424 65682 44546
SE/HF experiment
extrapolation
0.850 0.850 0.862 0.862 0.862 0.862
0.850 0.850 0.850 0.850 0.850 0.850
gies of the levels, confirms the correctness of the analysis performed of the spectrum of the Kr VII ion. ACKNOWLEDGMENTS I am grateful to P.S. Antsiferov and A.V. Nazarenko for their help in the experiments with the capillary source. REFERENCES 1. B. C. Fawcett, B. B. Jones, and R. Wilson, Proc. Phys. Soc. London 78, 1223 (1961). 2. M. Druetta and J. P. Buchet, J. Opt. Soc. Am. 66, 433 (1976). 3. A. E. Livingston, J. Phys. B 9, L215 (1976). 4. E. Jacquet, P. Boduch, M. Chantepie, et al., in Proceedings of 4th International Colloquium on Atomic Spectra and Oscillator Strengths; NIST Spec. Publ., No. 850, 136 (1983). 5. E. H. Pinnington, W. Ancbacher, and J. A. Kernahan, J. Opt. Soc. Am. B 1, 30 (1984). 6. A. E. Trigueiros, S. G. Petterson, and J. G. R. Almandos, Phys. Scr. 34, 164 (1986). 7. A. E. Trigueiros, S. G. Petterson, J. G. R. Almandos, and M. Gallardo, Phys. Lett. 141, 135 (1989). 8. T. Bouchama, M. Druetta, and S. Martin, J. Phys. B 22, 71 (1989). 9. E. H. Pinnington, A. Tauheed, W. Ancbacher, and J. A. Kernahan, J. Opt. Soc. Am. B 8, 193 (1991). 10. T. Shirai, J. Sugar, A. Musgrove, and W. L. Wiese, J. Phys. Chem. Ref. Data Monogr., No. 8, 435 (2000). 11. S. S. Churilov and Y. N. Joshi, Phys. Scr. 51, 196 (1995). 12. S. S. Churilov and Y. N. Joshi, J. Opt. Soc. Am. B 13, 11 (1996). 13. P. S. Antsiferov, S. S. Churilov, L. A. Dorokhin, et al., Phys. Scr. 62, 127 (2000). 14. R. L. Kelly, J. Phys. Chem. Ref. Data Suppl. 16 (1), 100 (1987). 15. R. D. Cowan, The Theory of Atomic Spectra and Structures (Univ. of California Press, Berkeley, 1981). 16. V. I. Azarov, Phys. Scr. 44, 528 (1991). 17. V. I. Azarov, Phys. Scr. 48, 656 (1993).
Translated by Yu. Sin’kov OPTICS AND SPECTROSCOPY
Vol. 93
No. 6
2002