The number of Ge i Ritz standards below 2000 Å has now been increased to approximately 100 lines with estimated uncertainties not exceeding 0.0009 Å, 68 of which have estimated uncertainties of 0.0003 Å. This extension is the end product of a systematic Fabry–Perot interferometric investigation which has extended the former interferometric region of 2019–4685 Å to 12 069 Å. Ninety-five interferometrically determined levels of Ge i are given, 72 of which have been improved by this effort.
Twenty-three lines of Ge ii were also measured interferometrically leading to 20 improved energy levels of this spectrum and to estimated splittings of the ng2G (n=5, 6, 7) terms. From the improved levels, twelve Ge ii Ritz standards from 999 to 1966 Å have been calculated with estimated uncertainties not exceeding 0.0009 Å. An improved series limit of Ge ii calculated from the nf2F and ng2G term series is 128 521.3 cm−1. This value made use of improved levels of this work and as yet unpublished data furnished by Shenstone.
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
The double letter in this column denotes the spectroscopic source used for the observation of the associated line. HC=liquid-nitrogen-cooled hollow cathode; GO=GeO+Ne at 46 mm Hg, electrodeless lamp; GB=GeBr4+Ne at about 48 mm Hg, electrodeless lamp; BO=both GO and GB above, the wavelength value is an average.
The values of these odd levels are taken from the atomic beam measurements of Deverall, Meissner, and Zissis.3
The values of these even levels are derived from the hollow cathode measurements of this paper.
All numbers are given in units of cm−1.
The four values given are, from top to bottom, the calculated value and the values observed from the hollow cathode, the GeBr4+Ne electrodeless lamp, and the GeO+Ne electrodeless lamp, respectively.
The differences shown are taken from the observed hollow cathode values.
This table does not list all of the known odd levels. For a complete list see Andrew and Meissner.6
The first double letter denotes the spectroscopic source upon which the corresponding level value is based. See footnote of Table I for the meanings of HC, GO, GB, and BO. AB=Atomic Beam; GI=electrodeless lamp containing GeI4.
The second group of letters denotes the observer(s). DMZ=Deverall, Meissner, and Zissis; VV=VanVeld and Meissner; HP=Humphreys and Paul; KA=Kaufman and Andrew.
This tables does not include levels of the 4s24pnf(n=4,5, ⋯) configurations.
Refer to Table III for definitions of symbols in these columns.
This level was numbered 21 by Andrew and Meissner.6
This level was numbered 25.1 by Andrew and Meissner.6
This line was identified by Professor A. G. Shenstone.
These are not true interferometric measurements but are based on near coincidence of fringe patterns in the 36-mm spacer only. It is felt that the 0.004Å is a generous estimate of the uncertainty.
All numbers in this table are in units of cm−1
The value 4s25s1S1/2=62 403.110 cm−1 is taken as the starting point for these improved level values and is obtained from the recent measurements of Wilkinson and Andrew.5
These are the observed values.
The uncertainties are based entirely on the uncertainties associated with the results given in Table VI and do not reflect any uncertainty in the absolute value of the 4s25s2S1/2 level.
The value 4s25s2S1/2=62 403.110 is taken as the starting point for these improved level values and is obtained from the recent measurements of Wilkinson and Andrew.5
Table IX
Ge ii—calculated vacuum-ultraviolet Ritz standards.
The intensities listed are those observed by Professor A. G. Shenstone.
The wavenumbers are calculated from the level values given in Table VIII and from the value of 4s24p2P3/2=1767.36±0.03 cm−1 which is taken from the recent work of Wilkinson and Andrew.5
The uncertainties listed are the sums of the uncertainties of the combining levels and do not reflect any uncertainty in the absolute values of the 4s25s2S1/2 level.
Table X
A sample series-limit calculation: the 5g–10g2G series of Ge ii. a=0.0190956a, b=−0.1505910, c=0.2748371; series limit=128 521.335 cm−1, rms=0.013 cm−1.
n
Exp. level
Calc. level
Dev.
5
110 868.51
110 868.506
0.004
6
116 266.79
116 266.793
−0.003
7
119 521.88
119 521.855
0.025
8
121 633.90
121 633.913
−0.013
9
123 081.39
123 081.394
−0.004
10
124 116.39
124 116.376
0.014
See modified Ritz-term formula.
Table XI
Series-limit values for Ge ii. The body of the table contains the series-limit value obtained from a least-square fit of a two- and three-parameter modified Ritz-term formula (see text) to the term members designated for the centers of gravity of 2F and 2G, respectively. The entry to the right of each series limit gives the root-mean-square deviation of the experimental level values from the corresponding values calculated from the series limit and term formula.
Members used
2F Series limit
rms
2G Series limit
rms
5-7
128 519.023 cm−1
0.001 cm−1
128 520.982 cm−1
0.001 cm−1
5-8
128 519.838
0.070
128 521.025
0.002
Two-parameter formula
5-9
128 520.136
0.082
128 521.043
0.016
5-10
128 520.336
0.094
128 521.123
0.027
5-9
128 521.282
0.021
128 521.220
0.011
Three-parameter formula
5-10
128 521.158
0.022
128 521.335
0.013
5-11
128 521.375
0.034
128 521.523
0.019
Tables (11)
Table I
Interferometric measurements in the Ge i spectrum.
The double letter in this column denotes the spectroscopic source used for the observation of the associated line. HC=liquid-nitrogen-cooled hollow cathode; GO=GeO+Ne at 46 mm Hg, electrodeless lamp; GB=GeBr4+Ne at about 48 mm Hg, electrodeless lamp; BO=both GO and GB above, the wavelength value is an average.
The values of these odd levels are taken from the atomic beam measurements of Deverall, Meissner, and Zissis.3
The values of these even levels are derived from the hollow cathode measurements of this paper.
All numbers are given in units of cm−1.
The four values given are, from top to bottom, the calculated value and the values observed from the hollow cathode, the GeBr4+Ne electrodeless lamp, and the GeO+Ne electrodeless lamp, respectively.
The differences shown are taken from the observed hollow cathode values.
This table does not list all of the known odd levels. For a complete list see Andrew and Meissner.6
The first double letter denotes the spectroscopic source upon which the corresponding level value is based. See footnote of Table I for the meanings of HC, GO, GB, and BO. AB=Atomic Beam; GI=electrodeless lamp containing GeI4.
The second group of letters denotes the observer(s). DMZ=Deverall, Meissner, and Zissis; VV=VanVeld and Meissner; HP=Humphreys and Paul; KA=Kaufman and Andrew.
This tables does not include levels of the 4s24pnf(n=4,5, ⋯) configurations.
Refer to Table III for definitions of symbols in these columns.
This level was numbered 21 by Andrew and Meissner.6
This level was numbered 25.1 by Andrew and Meissner.6
This line was identified by Professor A. G. Shenstone.
These are not true interferometric measurements but are based on near coincidence of fringe patterns in the 36-mm spacer only. It is felt that the 0.004Å is a generous estimate of the uncertainty.
All numbers in this table are in units of cm−1
The value 4s25s1S1/2=62 403.110 cm−1 is taken as the starting point for these improved level values and is obtained from the recent measurements of Wilkinson and Andrew.5
These are the observed values.
The uncertainties are based entirely on the uncertainties associated with the results given in Table VI and do not reflect any uncertainty in the absolute value of the 4s25s2S1/2 level.
The value 4s25s2S1/2=62 403.110 is taken as the starting point for these improved level values and is obtained from the recent measurements of Wilkinson and Andrew.5
Table IX
Ge ii—calculated vacuum-ultraviolet Ritz standards.
The intensities listed are those observed by Professor A. G. Shenstone.
The wavenumbers are calculated from the level values given in Table VIII and from the value of 4s24p2P3/2=1767.36±0.03 cm−1 which is taken from the recent work of Wilkinson and Andrew.5
The uncertainties listed are the sums of the uncertainties of the combining levels and do not reflect any uncertainty in the absolute values of the 4s25s2S1/2 level.
Table X
A sample series-limit calculation: the 5g–10g2G series of Ge ii. a=0.0190956a, b=−0.1505910, c=0.2748371; series limit=128 521.335 cm−1, rms=0.013 cm−1.
n
Exp. level
Calc. level
Dev.
5
110 868.51
110 868.506
0.004
6
116 266.79
116 266.793
−0.003
7
119 521.88
119 521.855
0.025
8
121 633.90
121 633.913
−0.013
9
123 081.39
123 081.394
−0.004
10
124 116.39
124 116.376
0.014
See modified Ritz-term formula.
Table XI
Series-limit values for Ge ii. The body of the table contains the series-limit value obtained from a least-square fit of a two- and three-parameter modified Ritz-term formula (see text) to the term members designated for the centers of gravity of 2F and 2G, respectively. The entry to the right of each series limit gives the root-mean-square deviation of the experimental level values from the corresponding values calculated from the series limit and term formula.