Hyperfine structure measurements of neutral atomic iodine (127I) in the infrared region (1800-6000 cm−1)

Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

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Hyperfine structure measurements of neutral atomic iodine (127 I) in the infrared region (180 0-60 0 0 cm−1 ) Chilukoti Ashok a,b, S.R. Vishwakarma b, Himal Bhatt b, M.N. Deo a,b,∗ a b

Homi Bhabha National Institute, Anushaktinagar, Trombay, Mumbai 400085, India High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India

a r t i c l e

i n f o

Article history: Received 16 May 2019 Revised 25 June 2019 Accepted 25 June 2019 Available online 26 June 2019 Keywords: Iodine atom Emission spectra Hyperfine structure Magnetic dipole coupling constant Electric quadrupole coupling constant Infrared region Fourier transform spectrometer

a b s t r a c t Experimental measurements of high resolution emission spectra of neutral atomic iodine (I I) have been extended to cover the mid-infrared spectral regions (180 0–60 0 0 cm−1 ) using Fourier transform spectroscopy. A total of 354 spectral lines are reported here in the above spectral range. While the region between 30 0 0 and 60 0 0 cm−1 were recorded using a conventional quartz Electrodeless Discharge lamps (EDL), spectra in the region 180 0–30 0 0 cm−1 were detected using specially prepared EDLs with a CaF2 window. Hyperfine structure analysis has been carried out on 224 spectral lines, of which 176 are reported for the first time. The magnetic dipole constant (A) and electric quadrupole constant (B) have been derived for 97 energy levels. © 2019 Elsevier Ltd. All rights reserved.

1. Introduction Atomic spectroscopy of iodine has been a subject of interest since many decades due to its rich hyperfine structure spanning a wide range of electromagnetic spectrum. However, comprehensive details of the hyperfine spectra in the complete spectral range from infrared to UV are still missing. Using various spectroscopic techniques, spectra of neutral atomic iodine (I I) have been reported in the past [1–10] to determine nuclear spin, spectral line positions and hyperfine structure (hfs) constants [11–17] from the measured spectral line positions. A brief discussion of past studies of I I and the details of its hyperfine structure can be found in ref. [16–17]. In our previous works [16–17], we extended the spectral measurements of I I to the near infrared (NIR) regions using Fourier Transform Spectroscopy (FTS) and reported many new transitions in the NIR (60 0 0–10,0 0 0 cm−1 ) and visible (10,0 0 0–25,0 0 0 cm−1 ) parts of the spectrum. The values of hyperfine structure constants were reported, in addition to the observation of singly ionized species [18]. However, high resolution spectroscopy in the IR regions poses some challenges, such as blending of atomic lines by molecular emission bands and poor optical transmission of quartz

∗ Corresponding author at: Bhabha Atomic Research Centre, HP&SRPD, Purnima Labs, Mumbai 40 0 085, India. E-mail address: [email protected] (M.N. Deo).

https://doi.org/10.1016/j.jqsrt.2019.06.029 0022-4073/© 2019 Elsevier Ltd. All rights reserved.

used for the preparation of Electrodeless Discharge Lamp (EDL) source. The complexity is further enhanced due to the overlapping with molecular rotational lines. Here, we have adopted a specially developed source-preparation methodology in order to observe spectral lines and hfs structure of I I in the mid-infrared region (180 0–60 0 0 cm−1 ) using FTS. This enabled us to observe 354 spectral lines including 224 well-resolved hfs structures reported in the present paper, which includes hfs studies on 176 spectral lines for the first time.

2. Experimental details The EDLs used for emission experiments are made up of a quartz tube of 6 mm outer diameter (OD) and 5 cm length. However, the optical transmission below 3900 cm−1 is very poor with the quartz EDL. This results in suppression of emission lines in the low energy infrared region. To overcome this difficulty, a CaF2 window of 2 mm thickness was sealed to one end of the EDL to obtain high optical transmission below 3900 cm−1 . Here, additional care has to be taken, so that the sealant should not be present inside the EDL. The tube is then cleaned and evacuated to 1.0 × 10−3 Torr. It was further subjected to several microwave discharge cleaning cycles with pure Ne gas (until a persistent color of Ne discharge was observed) evacuated to 1.0 × 10−5 Torr. If the tube is not sufficiently clean, small contamination in the EDL may generate emission spectra of the CO molecule, which may overlap with the

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

163

Fig. 1. Comparison of observed spectra between the (a) EDL with CaF2 window and (b) EDL with quartz. Nearly 100 lines were observed using an EDL with a CaF2 window, which were absent in the quartz EDL.

Fig. 2. Well resolved high resolution hfs structure of the spectral line at 2256.658 cm−1 observed using an EDL with a CaF2 window. The line is completely absent in a normal (all-quartz) EDL.

sample spectra. Also, any contamination due to the sealant may result in additional bands in the spectra. Another important consideration is that the operating power should be as low as possible, because the heat generated during the discharge can melt the sealant and break the EDL vacuum. Thus, in this case, the microwave power was limited to maximum 6 W. The experimental setup has been described in detail in refs. [16–18]. A high resolution Fourier transforms spectrometer (IFS 125 HR) equipped with KBr and CaF2 beam splitters with liquidnitrogen-cooled InSb detector was used to observe the spectra in the 180 0–60 0 0 cm−1 region. Various instrumental resolutions were applied with the maximum resolution of 0.002 cm−1 . The EDL was cooled using a cryo-cooling setup [16] to reduce the Doppler broadening of the spectral lines. Fig. 1 shows a comparison of observed spectra between the normal quartz EDL and the one with a CaF2 window. Nearly 100 extra lines were observed in the case of the CaF2 window lamp. Highresolution profiles of these lines could also be measured, as shown in Fig. 2 for the line at 2256.658 cm−1 with a well-resolved hfs pattern recorded using a CaF2 window EDL, which otherwise could not be studied. Noticeably, in the hfs structure, not only the strong

hfs components, but also the weak components (marked as i, j, and k) are also detected. An example of the importance of proper cleaning and evacuation of EDLs in such experiments is shown in Fig. 3(a), which indicates the appearance of CO molecular band near 2100 cm−1 . These rotational lines overlap with the emission lines of I I, which may hinder the unambiguous identification of hfs components. By considering the proper precautions while preparing the EDL, the molecular band intensity can be reduced considerably as shown in Fig. 3(b). 3. Hyperfine structure investigations Fig. 3 also presents an overview of observed spectra of I I in the entire spectral region of 180 0–60 0 0 cm−1 . In this spectral range, a total of 354 spectral lines were identified as I I transitions. Along with I I lines, Ne lines are also present in the spectra (Ne is used as buffer gas). The calibration of our measured spectra was carried out with respect to these standard Ne lines [19] to remove the minute deviations arising from emission sourcet instability. Table 1 represents the list of observed spectral lines and

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Table 1 Center of gravity wavenumber list of 354 observed spectral transitions of I I in the IR spectral region along with their classifications. The even and odd energy levels are taken from the NIST data base [20]. Here σ obs is the center of gravity wavenumber of the observed spectral lines. The value in parentheses represents the uncertainty. σ cal is the wavenumber calculated using the level energies given in the NIST database [20]. Asterisk (∗ ) denotes blended lines, which also includes those lines for which only one transition is known, but the structure appears to be blended.

σ obs (cm−1 )

σ cal (cm−1 )

Even Level Ee (cm−1 )

Je

Odd Level Eo (cm−1 )

Jo

1818.575(3) 1851.658(3) 1853.746(2) 1878.454(4) 1880.892(3) 1928.043(4) 1934.380(4) 1934.733(3) 1937.615(2) 1943.932(4) 1947.870(3) 1982.125(5) 2014.387(5) 2033.125(3) 2056.430(2) 2100.294(5) 2105.032(4) 2122.635(4) 2130.057(3)∗ 2130.057(3)∗ 2136.226(4) 2137.827(3) 2145.777(4) 2179.408(5) 2182.368(5) 2188.255(4) 2252.745(3) 2256.658(2) 2259.379(2) 2278.826(3) 2308.335(2) 2364.490(5) 2397.610(5) 2401.191(4) 2408.104(5) 2436.725(5) 2477.658(2) 2485.072(4) 2498.073(3) 2500.372(2) 2506.300(2) 2525.237(3) 2525.899(4) 2535.913(2) 2537.047(2) 2537.723(5) 2539.006(2) 2545.278(5) 2548.057(4) 2574.637(4)∗ 2580.694(3)∗ 2581.467(4) 2582.042(4) 2588.288(5) 2610.663(3) 2643.667(2) 2648.051(3) 2670.200(4) 2670.749(4) 2692.774(3) 2699.775(3) 2700.795(4) 2708.869(4) 2719.887(5)∗ 2727.505(3) 2737.758(2) 2749.234(5) 2754.630(5)

1818.552 1851.672 1853.755 1878.489 1880.911 1928.037 1934.397 1934.707 1937.634 1943.939 1947.889 1982.127 2014.413 2033.129 2056.427 2100.327 2105.030 2122.637 2130.045 2130.098 2136.224 2137.820 2145.767 2179.401 2182.350 2188.258 2252.759 2256.653 2259.372 2278.844 2308.334 2364.487 2397.657 2401.195 2408.147 2436.725 2477.678 2485.074

73,795.327 75,511.130 76,903.269 79,285.273 79,285.273 80,772.340 77,555.824 73,114.807 76,903.269 80,676.170 80,680.120 73,639.300 80,869.160 76,746.978 67,726.415 76,903.269 79,418.489 75,177.235 75,177.235 75,177.235 75,177.235 73,639.300 77,555.824 75,177.235 75,177.235 73,114.807 77,555.824 77,450.709 77,450.709 76,136.403 67,298.328 77,555.824 76,417.783 77,450.709 81,252.450 75,823.909 76,746.978 77,450.709 Unclassified Unclassified 77,555.824 Unclassified 82,385.430 Unclassified Unclassified 82,385.430 Unclassified 82,426.650 Unclassified Unclassified Unclassified Unclassified 82,426.650 Unclassified 74,587.415 76,136.403 75,177.235 63,186.758 72,294.881 68,549.743 70,354.834 75,714.423 76,106.548 74,587.415 76,004.731 76,106.548 76,136.403 72,294.881

5/2 7/2 5/2 ½ ½ 9/2 3/2 ½ 5/2 7/2 5/2 3/2 7/2 3/2 9/2 5/2 5/2 5/2 5/2 5/2 5/2 3/2 3/2 5/2 5/2 ½ 3/2 5/2 5/2 3/2 ½ 3/2 ½ 5/2 5/2 3/2 3/2 5/2

71,976.775 77,362.802 75,049.514 77,406.784 77,404.362 78,844.303 75,621.427 75,049.514 74,965.635 78,732.231 78,732.231 75,621.427 78,854.747 78,780.107 65,669.988 79,003.596 77,313.459 73,054.598 77,307.280 77,307.333 77,313.459 71,501.480 79,701.591 77,356.636 77,359.585 75,303.065 75,303.065 75,194.056 75,191.337 78,415.247 64,989.994 75,191.337 78,815.440 75,049.514 78,844.303 73,387.184 79,224.656 74,965.635

3/2 9/2 3/2 3/2 1/2 7/2 3/2 3/2 5/2 5/2 5/2 3/2 5/2 1/2 7/2 7/2 7/2 3/2 7/2 5/2 7/2 1/2 1/2 3/2 5/2 1/2 1/2 7/2 5/2 3/2 3/2 5/2 3/2 3/2 7/2 1/2 3/2 5/2

3/2

75,049.514

3/2

9/2

79,859.570

9/2

9/2

79,847.683

7/2

3/2

79,881.383

3/2

3/2

79,844.469

5/2

3/2 3/2 5/2 ½ 3/2 3/2 3/2 1/2 5/2 3/2 7/2 5/2 3/2 3/2

71,976.775 78,780.107 72,529.182 65,856.960 74,965.635 65,856.960 73,054.598 78,415.247 78,815.440 77,307.333 78,732.231 78,844.303 73,387.184 75,049.514

3/2 1/2 5/2 1/2 5/2 1/2 3/2 3/2 3/2 5/2 5/2 7/2 1/2 3/2

2506.310 2525.860

2537.747 2545.267

2582.181 2610.640 2643.704 2648.053 2670.202 2670.754 2692.783 2699.764 2700.824 2708.892 2719.918 2727.500 2737.755 2749.219 2754.633

hfs done

a

a a

a a a a a

a a a a a a a a a a a a a a

a

a a a a a a a a a

a a

(continued on next page)

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Table 1 (continued)

σ obs (cm−1 )

σ cal (cm−1 )

Even Level Ee (cm−1 )

Je

Odd Level Eo (cm−1 )

Jo

hfs done

2758.777(2) 2769.235(3) 2773.459(4) 2794.242(4) 2806.889(3) 2816.953(4) 2818.040(4) 2819.385(2) 2844.293(2) 2850.025(4) 2885.737(2) 2889.554(3) 2896.457(4) 2903.396(4) 2905.277(3) 2907.266(2) 2908.320(5) 2915.064(5) 2916.514(4) 2917.853(3) 2929.701(5) 2936.903(4) 2943.387(5) 2944.434(5) 2945.419(3) 2955.827(3) 2981.953(4) 2991.519(5) 3008.182(3) 3016.746(2) 3030.619(4) 3030.877(3) 3032.336(2) 3051.952(5) 3061.901(4) 3065.658(4) 3081.806(5) 3085.940(3) 3086.512(4) 3089.079(2) 3091.167(3) 3091.727(5) 3093.213(4) 3097.523(2) 3100.986(4) 3103.266(5) 3104.699(2) 3112.608(2) 3140.216(3) 3145.776(5) 3170.219(2) 3173.637(5) 3182.963(3) 3189.162(2) 3200.479(4) 3210.598(3) 3221.104(2) 3241.971(4) 3264.214(5) 3269.759(2) 3287.608(3) 3290.323(3) 3292.706(3) 3299.396(5)∗ 3299.396(5)∗ 3307.236(2) 3321.914(5) 3322.764(5) 3325.778(4) 3326.547(3) 3328.845(3) 3329.245(4)

2758.774 2769.221 2773.457 2794.243 2806.873 2816.947 2818.043 2819.369 2844.295 2850.016 2885.746 2889.552 2896.456 2903.397 2905.267 2907.259 2908.322 2915.064 2916.547 2917.871 2929.686 2936.883 2943.383 2944.414 2945.410 2955.854 2981.948 2991.531 3008.184 3016.745 3030.599 3030.838 3032.350 3051.950 3061.899 3065.684 3081.805 3085.935 3086.511 3089.071 3091.130 3091.729 3093.174 3097.491 3101.017 3103.206 3104.703 3112.605 3140.163 3145.778 3170.215 3173.611 3182.948 3189.16 3200.460 3210.551 3221.101 3241.956 3264.215 3269.760 3287.601 3290.320 3292.704 3299.384 3299.456 3307.230 3321.914 3322.753 3325.763 3326.546 3328.844 3329.239

68,615.734 74,587.415 74,587.415 78,415.670 76,417.783 74,587.415 79,395.897 74,587.415 75,898.893 76,004.731 68,615.734 68,559.540 72,294.881 70,151.201 68,549.743 75,714.423 75,823.909 68,559.540 75,898.893 68,587.859 76,903.269 76,903.269 68,587.859 76,903.269 75,898.893 75,898.893 75,511.130 75,823.909 72,294.881 75,823.909 76,417.783 75,823.909 70,354.834 76,106.548 71,903.736 75,714.423 76,136.403 74,587.415 61,819.779 70,151.201 78,415.670 75,898.893 76,746.978 76,746.978 75,714.423 77,555.824 75,898.893 78,415.670 75,704.140 71,903.736 61,819.779 77,450.709 79,030.992 78,415.670 75,177.235 77,450.709 75,511.130 77,555.824 68,549.743 78,891.187 71,903.736 71,903.736 70,354.834 76,106.548 75,704.140 78,415.670 78,943.341 78,891.187 75,898.893 72,294.881 73,977.715 76,136.403

1/2 3/2 3/2 1/2 1/2 3/2 3/2 3/2 5/2 7/2 1/2 7/2 3/2 5/2 3/2 1/2 3/2 7/2 5/2 5/2 5/2 5/2 5/2 5/2 5/2 5/2 7/2 3/2 3/2 3/2 1/2 3/2 3/2 5/2 5/2 1/2 3/2 3/2 3/2 5/2 1/2 5/2 3/2 3/2 1/2 3/2 5/2 1/2 9/2 5/2 3/2 5/2 3/2 1/2 5/2 5/2 7/2 3/2 3/2 3/2 5/2 5/2 3/2 5/2 9/2 1/2 5/2 3/2 5/2 3/2 7/2 3/2

65,856.960 77,356.636 71,813.958 75,621.427 79,224.656 77,404.362 82,213.940 77,406.784 73,054.598 78,854.747 71,501.480 65,669.988 75,191.337 73,054.598 65,644.476 72,807.164 78,732.231 65,644.476 78,815.440 65,669.988 79,832.955 79,840.152 65,644.476 79,847.683 78,844.303 78,854.747 72,529.182 78,815.440 75,303.065 72,807.164 73,387.184 78,854.747 73,387.184 73,054.598 74,965.635 78,780.107 73,054.598 71,501.480 64,906.290 67,062.130 81,506.800 72,807.164 79,840.152 79,844.469 78,815.440 80,659.030 79,003.596 75,303.065 78,844.303 75,049.514 64,989.994 80,624.320 82,213.940 81,604.830 71,976.775 80,661.260 78,732.231 80,797.780 71,813.958 75,621.427 75,191.337 75,194.056 67,062.130 72,807.164 79,003.596 81,722.900 75,621.427 82,213.940 79,224.656 75,621.427 77,306.559 72,807.164

1/2 3/2 1/2 3/2 3/2 1/2 5/2 3/2 3/2 5/2 1/2 7/2 5/2 3/2 5/2 3/2 5/2 5/2 3/2 7/2 7/2 5/2 5/2 7/2 7/2 5/2 5/2 3/2 1/2 3/2 1/2 5/2 1/2 3/2 5/2 1/2 3/2 1/2 5/2 3/2 1/2 3/2 5/2 5/2 3/2 5/2 7/2 1/2 7/2 3/2 3/2 5/2 5/2 1/2 3/2 7/2 5/2 3/2 1/2 3/2 5/2 7/2 3/2 3/2 7/2 3/2 3/2 5/2 3/2 3/2 9/2 3/2

a a a a a

a a a a a a a a a a a

a a a a a a a a a a,b a a a a,b a a

a a a a a a

a a a a a a,b a,b

a a a a,b a,b

(continued on next page)

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Table 1 (continued)

σ obs (cm−1 ) ∗

3329.571(4) 3329.571(4)∗ 3333.182(2) 3335.750(3) 3359.770(5) 3361.015(4) 3363.182(4) 3366.159(4) 3369.706(3) 3378.492(4) 3381.879(5) 3385.064(2) 3400.741(3) 3409.556(4) 3410.247(5) 3427.010(2) 3463.897(5)∗ 3463.897(5)∗ 3511.964(4)∗ 3511.964(4)∗ 3559.745(4) 3561.314(5) 3564.269(4) 3577.373(2) 3597.818(3) 3611.465(4) 3625.742(5) 3643.467(2) 3653.251(2) 3663.829(3) 3668.008(5)∗ 3681.573(2) 3692.345(4) 3703.751(5) 3709.970(5) 3712.712(4) 3717.338(4) 3717.696(5) 3727.936(4) 3765.063(3) 3771.766(5) 3774.478(5) 3797.080(4) 3824.702(4) 3826.166(5) 3828.227(3) 3841.678(3) 3842.975(4) 3847.159(5) 3848.653(4) 3854.827(5) 3860.932(3) 3875.367(3) 3893.839(2) 3900.475(5) 3903.378(3) 3922.142(2) 3925.567(3) 3926.553(4) 3928.976(4) 3938.405(2) 3939.783(5) 3941.313(5) 3945.583(4) 3948.796(4) 3959.238(3) 3969.654(3) 3977.709(5) 3979.440(4) 3981.483(5)

σ cal (cm−1 )

Even Level Ee (cm−1 )

Je

Odd Level Eo (cm−1 )

Jo

3329.565 3329.618 3333.173 3335.744 3359.794 3361.041 3363.185 3366.156 3369.711 3378.472 3381.870 3385.087 3400.747 3409.565 3410.212 3427.032 3463.600 3463.950 3511.953 3512.006 3559.749 3561.309 3564.258 3577.366 3597.865 3611.457 3625.740 3643.453 3653.250 3663.846 3668.033 3681.569 3692.380 3703.749 3710.005 3712.724 3717.336 3717.691 3727.927 3765.062 3771.778 3774.470 3797.062 3824.697 3826.361 3828.224 3841.673 3842.952 3847.134 3848.671 3854.839 3860.929 3875.372 3893.827 3900.465 3903.376 3922.118 3925.552 3926.528 3928.950 3938.426 3939.814 3941.323 3945.576 3948.790 3959.213 3969.642 3977.706 3979.439 3981.478

73,977.715 73,977.715 75,511.130 73,977.715 76,746.978 68,615.734 76,417.783 78,415.670 75,898.893 76,746.978 73,977.715 73,977.715 75,823.909 79,030.992 80,772.340 68,549.743 76,417.783 76,417.783 73,795.327 73,795.327 68,549.743 73,795.327 73,795.327 76,106.548 68,587.859 73,795.327 68,615.734 68,549.743 68,559.540 79,285.273 73,639.300 68,587.859 76,746.978 76,136.403 78,904.061 78,904.061 73,639.300 71,903.736 79,030.992 73,639.300 79,393.205 79,395.897 79,418.489 61,819.779 75,177.235 76,004.731 78,891.187 76,004.731 75,823.909 76,903.269 76,004.731 79,054.985 63,186.758 78,943.341 75,714.423 76,136.403 75,898.893 78,891.187 73,477.834 73,477.834 78,904.061 76,746.978 68,587.859 75,898.893 75,898.893 79,150.550 68,559.540 78,943.341 68,549.743 79,030.992

7/2 7/2 7/2 7/2 3/2 1/2 1/2 1/2 5/2 3/2 7/2 7/2 3/2 3/2 9/2 3/2 1/2 1/2 5/2 5/2 3/2 5/2 5/2 5/2 5/2 5/2 1/2 3/2 7/2 1/2 3/2 5/2 3/2 3/2 7/2 7/2 3/2 5/2 3/2 3/2 1/2 3/2 5/2 3/2 5/2 7/2 3/2 7/2 3/2 5/2 7/2 9/2 1/2 5/2 1/2 3/2 5/2 3/2 1/2 1/2 7/2 3/2 5/2 5/2 5/2 7/2 7/2 5/2 3/2 3/2

77,307.280 77,307.333 78,844.303 77,313.459 73,387.184 71,976.775 73,054.598 75,049.514 72,529.182 80,125.45 77,359.585 77,362.802 79,224.656 75,621.427 77,362.128 71,976.775 79,881.383 79,881.733 77,307.280 77,307.333 64,989.994 77,356.636 77,359.585 72,529.182 64,989.994 77,406.784 64,989.994 64,906.290 64,906.290 75,621.427 77,307.333 64,906.290 73,054.598 79,840.152 75,194.056 75,191.337 77,356.636 75,621.427 75,303.065 77,404.362 75,621.427 75,621.427 75,621.427 65,644.476 79,003.596 79,832.955 75,049.514 79,847.683 71,976.775 73,054.598 79,859.570 75,194.056 67,062.130 75,049.514 71,813.958 80,039.779 71,976.775 74,965.635 77,404.362 77,406.784 74,965.635 72,807.164 72,529.182 79,844.469 79,847.683 75,191.337 72,529.182 74,965.635 72,529.182 75,049.514

7/2 5/2 7/2 7/2 1/2 3/2 3/2 3/2 5/2 5/2 5/2 9/2 3/2 3/2 11/2 3/2 3/2 1/2 7/2 5/2 3/2 3/2 5/2 5/2 3/2 3/2 3/2 5/2 5/2 3/2 5/2 5/2 3/2 5/2 7/2 5/2 3/2 3/2 1/2 1/2 3/2 3/2 3/2 5/2 7/2 7/2 3/2 7/2 3/2 3/2 9/2 7/2 3/2 3/2 1/2 3/2 3/2 5/2 1/2 3/2 5/2 3/2 5/2 5/2 7/2 5/2 5/2 5/2 5/2 3/2

hfs done

a a a a a a a

a a

a b b a

a a a,b a,b a,b a a,b

a b a,b a a a a a a,b

a a a a a a a a a a a a a

a a,b a a,b

(continued on next page)

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

167

Table 1 (continued)

σ obs (cm−1 )

σ cal (cm−1 )

Even Level Ee (cm−1 )

Je

Odd Level Eo (cm−1 )

Jo

hfs done

3982.201(5) 4005.177(4) 4009.950(3) 4010.987(3) 4020.568(2) 4037.185(3) 4057.767(4)∗ 4057.767(4)∗ 4065.358(3) 4090.123(4) 4092.841(3) 4093.758(3) 4096.094(5) 4120.470(4) 4125.479(2) 4129.795(3) 4154.875(3) 4168.639(2) 4184.900(5) 4191.432(4) 4203.157(4) 4204.558(5) 4212.952(5) 4217.761(4) 4219.321(4) 4227.161(3) 4235.752(4) 4241.823(5) 4289.548(2) 4291.972(3) 4293.256(3) 4303.964(5) 4318.448(4) 4321.827(4) 4322.438(3)∗ 4322.438(3)∗ 4325.706(4) 4333.341(3) 4336.547(5) 4343.678(5) 4348.414(2) 4368.985(3) 4374.076(3) 4396.108(4) 4430.294(4) 4438.871(3) 4441.036(5) 4466.773(3) 4481.221(4) 4497.877(3) 4504.861(4) 4506.734(4) 4515.636(3) 4603.829(3) 4610.807(5) 4644.065(5) 4654.349(3) 4655.713(3) 4667.242(4) 4678.428(2) 4694.676(5) 4710.360(3) 4720.622(3) 4755.790(4) 4770.186(3) 4771.417(5) 4808.124(5) 4809.465(3) 4814.437(4) 4836.507(4) 4837.432(5) 4841.613(5)

3982.208 4005.157 4009.951 4011.001 4020.560 4037.182 4057.474 4057.864 4065.357 4090.140 4092.832 4093.751 4096.105 4120.487 4125.460 4129.773 4154.870 4168.640 4184.915 4191.430 4203.152 4204.560 4212.943 4217.796 4219.305 4227.152 4235.759 4241.829 4289.555 4291.977 4293.255 4303.871 4318.470 7321.825 4322.501 4322.445 4325.696 4333.339 4336.553 4343.691 4348.440 4368.975 4374.087 4396.111 4430.262 4438.864 4441.008 4466.739 4481.213 4497.874 4504.855 4506.725 4515.630 4603.825 4610.801 4644.058 4654.26 4655.720 4667.233 4678.447 4694.680 4710.358 4720.626 4755.786 4770.203 4771.450 4808.107 4809.457 4814.434 4836.503 4837.441 4841.606

79,285.273 74,587.415 75,823.909 75,823.909 75,823.909 61,819.779 75,823.909 75,823.909 79,030.992 79,393.205 79,395.897 60,896.243 76,903.269 75,714.423 75,704.140 76,106.548 75,704.140 77,555.824 79,150.550 68,615.734 67,298.328 79,395.897 75,714.423 76,746.978 68,587.859 79,418.489 79,285.273 73,114.807 73,114.807 73,114.807 79,914.682 76,903.269 75,511.130 75,511.130 75,823.909 76,136.403 79,947.123 75,511.130 75,511.130 79,393.205 75,511.130 79,418.489 76,903.269 77,450.709 79,395.897 68,615.734 76,417.783 68,587.859 70,151.201 70,354.834 68,549.743 70,151.201 67,298.328 76,417.783 70,354.834 79,947.123 76,004.731 75,177.235 75,177.235 67,298.328 70,354.834 70,354.834 79,914.682 79,947.123 76,746.978 68,615.734 76,417.783 76,417.783 70,151.201 70,354.834 68,549.743 71,903.736

1/2 3/2 3/2 3/2 3/2 3/2 3/2 3/2 3/2 1/2 3/2 1/2 5/2 1/2 9/2 5/2 9/2 3/2 7/2 1/2 1/2 3/2 1/2 3/2 5/2 5/2 1/2 1/2 1/2 1/2 5/2 5/2 7/2 7/2 3/2 3/2 3/2 7/2 7/2 1/2 7/2 5/2 5/2 5/2 3/2 1/2 1/2 5/2 5/2 3/2 3/2 5/2 1/2 1/2 3/2 3/2 7/2 5/2 5/2 1/2 3/2 3/2 5/2 3/2 3/2 1/2 1/2 1/2 5/2 3/2 3/2 5/2

75,303.065 78,592.572 71,813.958 79,834.910 79,844.469 65,856.960 79,881.383 79,881.773 74,965.635 75,303.065 75,303.065 64,989.994 72,807.164 79,834.910 79,829.600 71,976.775 79,859.010 73,387.184 74,965.635 72,807.164 71,501.480 75,191.337 71,501.480 72,529.182 72,807.164 75,191.337 75,049.514 77,356.636 77,404.362 77,406.784 75,621.427 81,207.14 79,829.600 79,832.955 71,501.408 71,813.958 75,621.427 79,844.469 79,847.683 75,049.514 79,859.570 75,049.514 72,529.182 73,054.598 74,965.635 73,054.598 71,976.775 73,054.598 65,669.988 65,856.960 73,054.598 65,644.476 71,813.958 71,813.958 74,965.635 75,303.065 80,659.030 79,832.955 79,844.469 71,976.775 75,049.514 65,644.476 75,194.056 75,191.337 71,976.775 73,387.184 81,225.890 81,227.240 74,965.635 75,191.337 73,387.184 67,062.130

1/2 5/2 1/2 3/2 5/2 1/2 3/2 1/2 5/2 1/2 1/2 3/2 3/2 3/2 9/2 3/2 11/2 1/2 5/2 3/2 1/2 5/2 1/2 5/2 3/2 5/2 3/2 3/2 1/2 3/2 3/2 7/2 9/2 7/2 1/2 1/2 3/2 5/2 7/2 3/2 9/2 3/2 5/2 3/2 5/2 3/2 3/2 3/2 7/2 1/2 3/2 5/2 1/2 1/2 5/2 1/2 5/2 7/2 5/2 3/2 3/2 5/2 7/2 5/2 3/2 1/2 1/2 3/2 5/2 5/2 1/2 3/2

a,b a a a a

a a a a,b a a a a a,b a,b a a a,b a a,b a,b a b a,b a,b

a a a

a a a a,b a,b a a a,b a,b a,b a,b a,b a a a a a,b a a b

a,b a a,b a,b

(continued on next page)

168

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

Table 1 (continued)

σ obs (cm−1 )

σ cal (cm−1 )

Even Level Ee (cm−1 )

Je

Odd Level Eo (cm−1 )

Jo

hfs done

4865.175(3) 4897.615(5) 4898.317(4) 4921.500(4) 4937.421(5) 4948.236(3) 4949.045(3) 4953.286(4) 4957.210(4) 4960.726(2) 5012.426(3) 5025.735(5) 5026.642(3) 5040.139(3) 5042.860(4) 5064.712(3) 5068.999(2) 5095.151(3) 5111.912(4) 5113.189(3) 5114.180(2) 5146.392(5) 5161.212(3) 5212.797(5) 5232.759(2) 5242.355(3) 5244.920(4) 5245.470(4) 5260.876(3) 5266.601(5) 5308.327(5) 5364.843(2) 5387.876(3) 5390.931(4) 5403.569(3)∗ 5403.569(3)∗ 5409.724(5) 5448.548(5) 5452.372(3) 5455.868(4) 5458.873(4) 5470.233(5) 5473.947(3) 5479.410(4) 5482.105(2) 5484.847(2) 5486.045(5) 5502.340(5) 5508.836(3) 5513.017(4) 5578.316(3) 5608.511(3) 5621.671(4) 5630.602(5) 5641.433(5) 5677.823(4) 5688.634(2) 5690.560(3) 5690.950(5) 5710.527(4) 5714.469(2) 5725.308(5) 5746.867(3) 5756.273(5) 5776.104(3) 5834.915(4) 5836.593(4) 5868.722(5) 5888.743(3) 5898.091(4) 5956.290(5) 5976.389(4)

4865.168 4897.609 4898.313 4921.527 4937.413 4948.231 4949.047 4953.272 4957.120 4960.717 5012.452 5025.881 5026.642 5040.136 5042.855 5064.704 5068.987 5095.112 5111.903 5113.190 5114.176 5146.387 5161.207 5212.769 5232.751 5242.351 5244.911 5245.498 5260.863 5266.593 5308.247 5364.840 5387.850 5390.880 5403.544 5403.597 5409.723 5448.544 5452.364 5455.849 5458.865 5470.226 5473.934 5479.405 5482.114 5484.833 5486.064 5502.337 5508.836 5512.890 5578.284 5608.506 5621.682 5630.606 5641.426 5677.823 5688.610 5690.530 5690.953 5710.535 5714.485 5725.280 5746.822 5756.270 5776.076 5834.923 5836.589 5868.772 5888.743 5898.089 5956.306 5976.394

79,914.682 79,947.123 70,151.201 77,450.709 73,477.834 70,354.834 79,914.682 73,639.300 75,704.140 60,896.243 72,294.881 73,977.715 77,555.824 70,151.201 70,151.201 72,294.881 76,136.403 76,106.548 72,294.881 75,511.130 74,587.415 66,355.093 70,151.201 76,004.731 72,294.881 61,819.779 70,151.201 76,746.978 80,882.290 70,354.834 75,898.893 70,354.834 80,690.915 80,693.945 71,903.736 71,903.736 71,903.736 70,354.834 74,587.415 71,903.736 66,355.093 70,151.201 77,450.709 80,782.470 80,676.170 80,676.170 80,680.120 78,889.521 67,298.328 75,704.140 80,772.340 78,415.670 66,355.093 80,680.120 80,690.94 80,869.160 75,511.130 75,511.130 80,882.290 80,676.170 80,680.120 80,690.915 73,477.834 67,298.328 80,825.590 78,889.521 78,891.187 76,746.978 78,943.341 79,285.273 66,020.469 79,030.992

5/2 3/2 5/2 5/2 1/2 3/2 5/2 3/2 9/2 1/2 3/2 7/2 3/2 5/2 5/2 3/2 3/2 5/2 3/2 7/2 3/2 3/2 5/2 7/2 3/2 3/2 5/2 3/2 5/2 3/2 5/2 3/2 3/2 1/2 5/2 5/2 5/2 3/2 3/2 5/2 3/2 5/2 5/2 3/2 7/2 7/2 5/2 1/2 1/2 9/2 9/2 1/2 3/2 5/2 3/2 7/2 7/2 7/2 5/2 7/2 5/2 3/2 1/2 1/2 1/2 1/2 3/2 3/2 5/2 1/2 5/2 3/2

75,049.514 75,049.514 75,049.514 72,529.182 78,415.247 75,303.065 74,965.635 78,592.572 80,661.260 65,856.960 77,307.333 79,003.596 72,529.182 75,191.337 75,194.056 77,359.585 81,205.390 81,201.660 77,406.784 80,624.320 79,701.591 71,501.480 64,989.994 81,217.500 67,062.130 67,062.130 64,906.290 71,501.480 75,621.427 75,621.427 81,207.140 64,989.994 75,303.065 75,303.065 77,307.280 77,307.333 77,313.459 64,906.290 80,039.779 77,359.585 71,813.958 75,621.427 71,976.775 75,303.065 75,194.056 75,191.337 75,194.056 73,387.184 72,807.164 81,217.030 75,194.056 72,807.164 71,976.775 75,049.514 75,049.514 75,191.337 81,199.740 81,201.660 75,191.337 74,965.635 74,965.635 74,965.635 79,224.656 73,054.598 75,049.514 73,054.598 73,054.598 82,615.750 73,054.598 73,387.184 71,976.775 73,054.598

3/2 3/2 3/2 5/2 3/2 1/2 5/2 5/2 7/2 1/2 5/2 7/2 5/2 5/2 7/2 5/2 5/2 7/2 3/2 5/2 1/2 1/2 3/2 9/2 3/2 3/2 5/2 1/2 3/2 3/2 7/2 3/2 1/2 1/2 7/2 5/2 7/2 5/2 3/2 5/2 1/2 3/2 3/2 1/2 7/2 5/2 7/2 1/2 3/2 11/2 7/2 3/2 3/2 3/2 3/2 5/2 9/2 7/2 5/2 5/2 5/2 5/2 3/2 3/2 3/2 3/2 3/2 1/2 3/2 1/2 3/2 3/2

a a a a,b a,b a,b a

a: hfs in this work., b: hfs in previous work [13].

a,b a,b a a,b a,b a,b

a a a,b a,b a,b a,b a,b a a,b a a a

a,b a,b a a a a a

a a,b

a,b a a a

a a a a a a a a a

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

Table 2 Even energy levels of I I and their experimentally derived hfs A and B constants in mK (1 mK = 0.001 cm−1 ) in comparison with previous literature. Electronic Configuration

Even Level Ee (cm−1 )

5s2 5p4 (3 P2 )6s [2]3/2

56,092.881

AExp

BExp

A

B

17.75(30) 18.09(11) 17.97(76) 47.27(10) 47.29(33) 47.43(20) 47.79(73)

−13.3(10) −13.40(33) −13.42(75) −35.54(30) −34(4) −36.63(67) −36.02(86)

[13] [16] [17] [13] [14] [15] [17]

22.57(10) 22.68(24) 22.65(17) 22.60(13) 22.58(61) −3.97(7) −5.35(20) −5.54(19)

14.5(10) 14(1) 14.51(67) 14.16(37) 13.77(84)

[13] [14] [15] [16] [17] [15] [16] [17]

∗

[2]5/2

54,633.460

5s2 5p4 (3 P1 )6s [1]3/2

61,819.779

22.32(38)

[1]1/2

63,186.758

−4.15(15)

5s2 5p4 (3 P0 )6s [0]1/2

60,896.243

53.55(23)

5s2 5p4 (1 D2 )6s [2]5/2

68,587.859

82.40(11)

72.69(73)

[2]3/2

68,549.743

60.65(19)

36.9(12)

5s2 5p4 (3 P2 )7s [2]5/2

71,903.736

30.65(33)

−34.2(14)

[2]3/2 5s2 5p4 (3 P1 )7s [1]3/2

72,294.881

33.78(36)

21.03(61)

78,891.187

6.41(19)

13.52(55)

[1]1/2

79,285.273

7.06(42)

5s2 5p4 (3 P0 )7s [0]1/2

78,415.670

13.89(25)

5s2 5p4 (3 P2 )8s [2]5/2

77,450.709

[2]3/2

77,555.824

35.88(29)

5s2 5p4 (3 P2 )9s [2]5/2

79,914.682

[2]3/2

14.02(56)

53.58(5) 53.22(28) 53.77(7) 53.96(43)

Refs.

[13] [14] [15] [17]

82.99(10) 82.95(15) 83.19(10) 82.99(5) 82.35(62) 60.47(10) 59.08(85) 60.71(7) 60.31(22)

71.76(100) 70(1) 69.91(50) 72.61(7) 72.87(52) 36.7(10) 36(4) 36.39(33) 36.9(24)

[13] [14] [15] [16] [17] [13] [14] [15] [17]

30.36(5) 30.62(9) 33.53(10)

−33.82(100) −32.53(33) −20.82(50)

[13] [16] [13]

6.49(20) 6.94(23) 6.2(3) 6.80(53) 5.84(20) 7.50(8) 7.62(78)

15.37(200) 13.67(47)

[13] [17] [13] [14] [15] [16] [17]

13.55(5) 14.40(56) 13.48(3) 14.54(8)

[13] [14] [15] [17]

27.23(5) 27.39(33) 26.91(66)

−34.64(50) −31.02(33) −34.47(2)

[13] [15] [17]

−22.16(47)

36.07(20) 35.85(34) 36.06(33) 36.49(32) 35.72(33)

−22.81(80) −26(1) −23.35(33) −22.08(77) −21.8(11)

[13] [14] [15] [16] [17]

26.14(33)

−31.6(10)

26.35(20)

−29.95(67)

[15]

79,947.123

36.96(51)

−23.4(10)

36.98(10) 36.83(33) 40.69(89)

−23.95(100) −14.6(100) −23.96(5)

[13] [15] [17]

5s2 5p4 (3 P2 )5d [4]9/2

67,726.415

13.39(9)

−31.68(43)

[4]7/2

68,559.540

17.52(8)

−27.17(37)

13.49(10) 13.39(7) 13.42(7) 17.55(10) 17.75(17) 17.57(13) 17.54(25)

−31.48(200) −31.86(85) −31.74(35) −27.45(400) −28.89(67) −26.78(74) −26.84(97)

[13] [16] [17] [13] [15] [16] [17] (continued on next page)

169

170

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

Table 2 (continued) Electronic Configuration

Even Level Ee (cm−1 )

[3]7/2

66,015.023

[3]5/2

66,020.469

21.34(32)

4.70(55)

[2]5/2

70,151.201

15.43(27)

4.87(75)

[2]3/2

70,354.834

21.10(21)

22.55(89)

[1]3/2

66,355.093

33.34(26)

10.39(115)

[1]1/2

67,298.328

38.22(80)

[0]1/2

68,615.734

94.30(34)

5s2 5p4 (3 P1 )5d [3]7/2

73,977.715

−2.22(22)

−0.77(35)

[3]5/2

75,177.235

9.67(17)

−4.39(98)

[2]5/2

75,898.893

5.21(36)

13.95(83)

[2]3/2

75,823.909

11.57(31)

−3.08(36)

[1]3/2

74,587.415

17.69(28)

0.80(52)

[1]1/2

73,114.807

28.41(49)

73,795.327 73,639.300

8.82(49)

2

AExp

BExp

A

B

Refs.

10.12(10) 10.21(17) 10.42(6) 11.01(82) 21.59(20) 21.57(15) 21.41(7) 21.57(8) 22.06(89) 15.46(10) 15.84(16) 14.40(9) 21.08(10) 21.46(29) 21.35(17) 20.96(5) 32.59(5) 32.55(27) 32.56(7) 32.96(6) 34.60(74) 37.8(2) 37.91(23) 39.33(67) 37.04(93) 94.46(10) 94.56(23) 94.42(4) 94.43(4)

11.24(100) 6.17(67) 10.89(30) 11.0(3) 4(4) 6(1) 5.90(33) 6.05(25) 5.99(69) 4.1(5) −3.67(160) 4.73(68) 22.8(5) 20(1) 16.34(170) 20.73(63) 10.96(50) 8(1) 9.61(33) 9.53(24) 12.1(10)

[13] [15] [16] [17] [13] [14] [15] [16] [17] [13] [15] [16] [13] [14] [15] [16] [13] [14] [15] [16] [17] [13] [14] [15] [17] [13] [14] [16] [17]

−1.92(10) −1.46(6) 9.79(10) 9.95(3) 9.84(10) 4.33(10) 5.04(44) 11.49(30) 11.14(53)

1.21(50) 1.30(29) −4.2(10) −4.32(75) −4.0(14) 11.31 14.27(25) −3.26(50) −2.90(42)

[13] [16] [13] [16] [17] [13] [17] [13] [17]

17.47(10) 17.62(3) 28.86(5) 30.48(12)

1(1) 0.79(90)

[13] [16] [13] [16]

0.7(10) 9.01(5)

5(1) −9.34(50)

[13] [13]

294.77(2) 14.34(40) 15.08(97) 7.07(94)

−14.34(85) −11.81(76) −8.71(98)

[13] [16] [17] [17]

4 3

5s 5p ( P0 )5d [2]5/2 [2]3/2 5s2 5p4 (1 D2 )5d [0]1/2 [1]3/2

73,477.834 81,072.615

−9.6(17)

294.50(44)

[3]5/2 5s2 5p4 (3 P2 )6d [4]9/2 [4]7/2

82,144.510 75,704.140 76,004.731

14.21(42) 15.78(26)

−36.8(13) −21.51(64)

[3]7/2

75,511.130

12.78(43)

−10.16(71)

[3]5/2

76,106.548

7.86(39)

−21.08(95)

[2]5/2

76,903.269

12.16(33)

12.12(64)

[2]3/2 [1]3/2

76,746.978 76,136.403

−5.76(57) 5.37(22)

4.34(89) 5.58(37)

[1]1/2

76,417.783

48.66(37)

14.24(75) 16.03(10) 18.51(74) 12.88(10) 12.88(3) 12.84(50) 7.74(10) 7.54(28) 6.98(21) 11.37(45) 11.77(30) −7.64(64) 4.72(10) 4.92(13) 5.79(7) 48.63(30) 48.73(57) 48.60(33) 48.79(12) 49.36(80)

−35.6(10) −20.86(100) −20.85(88) −10.15(100) −10.13(71) −10.14(88) −20.33(100) −19.67(81) −19.35(7) 7(3) 12.00(98) 4.50(86) 5.28(100) 5.98(69) 5.60(6)

[17] [13] [17] [13] [16] [17] [13] [16] [17] [14] [17] [17] [13] [16] [17] [13] [14] [15] [16] [17] (continued on next page)

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

171

Table 2 (continued) Electronic Configuration

Even Level Ee (cm−1 )

AExp

[0]1/2

75,714.423

25.30(24)

5s2 5p4 (3 P2 )7d [4]9/2

79,054.985

14.28(26)

−34.26(88)

[4]7/2

79,150.550

17.65(22)

−27.68(39)

[3]7/2

78,904.061

15.06(16)

−11.27(42)

[3]5/2

78,943.341

17.85(24)

−6.47(29)

[2]5/2

79,418.489

14.78(56)

4.9(12)

[2]3/2

79,395.897

4.53(53)

16.09(61)

[1]3/2

79,030.992

21.23(49)

3.87(97)

[1]1/2

78,889.521

2.13(87)

[0]1/2

79,393.205

1.88(40)

5s2 5p4 (3 P2 )8d [4]9/2 [4]7/2 [3]7/2 [2]3/2 [1]3/2 [1]1/2 [3]5/2 5s2 5p4 nd 1/2

BExp

A

B

25.33(40) 25.42(18) 25.05(48)

80,772.340 80,869.160 80,676.170 80,782.470 80,690.940 80,693.970 80,680.120

24.95(62)

−9.85(79)

22.93(26) −15.07(39) 17.45(70)

1.82(140)

80,825.560

49.63(75)

Refs.

[13] [16] [17]

14.49(20) 14.31(72)

−11.25(65) −34.8(10)

[16] [17]

14.49(20) 14.88(89) 17.68(10) 17.24(4) 15.06(10) 14.34(53) 14.84(20) 10.14(25) 5.90(55) 3.84(33) 5.06(33) 4.33(41) 21.17(10) 20.48(13) 21.25(14) 21.53(90) 2.66(23) 1.96(87) 1.32(17) 1.50(82)

−11.25(65) −11.25(57) −6.2(10) −6.32(21) 4.3(10) 12(6) 3.87(67) 7.60(57) 13(2) 21.4(10) 13.31(81) 16.77(65) 5.37(50) 1(5) 5.19(73) 4.89(68)

[16] [17] [13] [17] [13] [14] [15] [17] [14] [15] [16] [17] [13] [14] [16] [17] [16] [17] [16] [17]

14.21(62) 25.25(58) 12.94(75) 11.87(75) 24.82(85) −15.07(39)

−29.05(59) −5.40(88) 25.81(73) 7.80(84) 0.5(11)

[17] [17] [17] [17] [17] [17]

−6.0(14)

∗

The numbers in parentheses denote the uncertainty on the level of one standard deviation in the units of the last digit of the value, e.g., 17.75(30) denotes 17.75 ± 0.30.

Fig. 3. (a) Appearance of CO molecular band at nearly 2100 cm−1 which is overlapping with the emission lines of I I. (b) The molecular band intensity is considerably reduced by properly cleaning the EDL.

172

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Table 3 Odd energy levels of I I and their experimentally derived hfs A and B constants in mK (1 mK = 0.001 cm−1 ) in comparison with previous literature. Electronic Configuration

Eo (cm−1 )

5s2 5p5 2 P3/2 5s2 5p5 2 P1/2 5s2 5p4 (3 P2 )6p [3]7/2

0.000 7602.970 65,669.988

19.25(16)

−37.70(76)

[3]5/2

65,644.476

24.16(27)

−22.38(87)

[2]5/2

64,906.290

25.27(31)

−19.45(42)

[2]3/2

64,989.994

35.24(32)

[1]3/2

67,062.130

29.23(42)

[1]1/2

65,856.960

57.72(56)

5s2 5p4 (3 P1 )6p [2]5/2

72,529.182

−6.47(42)

15.99(81)

[2]3/2

72,807.164

−0.59(15)

16.9(11)

[1]3/2

73,054.598

2.35(31)

−16.04(93)

[1]1/2

73,387.184

−31.45(89)

[0]1/2

71,501.480

8.37(52)

5s2 5p4 (3 P0 )6p [1]3/2

71,976.775

0.37(24)

[1]1/2

71,813.958

−6.55(36)

5s2 5p4 (1 D2 )6p [3]7/2

79,003.596

50.03(18)

71.25(85)

[3]5/2

78,592.572

67.38(22)

69.08(87)

[2]5/2

80,125.450

[2]3/2

80,039.779

74.98(35)

30.44(61)

AExp

BExp

A

B

27.59(5)∗ 219.75(10)

38.18(10)

[13] [13]

19.57(5) 19.49(12) 19.24(67) 24.03(10) 26.15(46) 27.87(74) 25.31(10) 26.73(47) 25.38(33) 26.32(24) 25.19(59)

− 36.84(50) −38.11(68) −37.40(83) −22.04(50) −22.85(71) −22.06(67) −18.86(100) −16(4) −17.7(10) −19.96(73) −19.36(48)

[13] [16] [17] [13] [16] [17] [13] [14] [15] [16] [17]

−23.23(84)

35.38(10) 35.21(43) 35.36(20) 35.39(15) 35.29(42)

−23.56(100) −25(2) −23.52(67) −23.88(89) −25.07(69)

[13] [14] [15] [16] [17]

−0.56(55)

29.13(5) 29.38(40) 28.92(10) 29.34(19) 29.43(95)

−0.45(50) 0(2) −0.70(33) −0.45(60) −0.43(5)

[13] [14] [15] [16] [17] [13] [14] [15] [16] [17]

57.25(5) 57.04(35) 57.34(7) 57.51(18) 58.73(77)

−0.74(56)

Refs.

−5.79(5) −6.01(43) −0.53(10) −0.56(4) −0.51(17) 2.18(5) 2.33(20) 2.19(63) −31.46(5) −31.57(10) −31.59(7) −32.07(5) −33(1) 8.50(5) 8.22(26) 7.90(38)

14.19(50) 14.29(19) 16.14(20) 16.09(33) 16.20(38) −14.58(50) −14.01(67) −16(1)

[13] [17] [13] [16] [17] [13] [15] [17] [13] [14] [15] [16] [17] [13] [16] [17]

0.12(9) 0.18(19)

−0.72(86) −0.83(58)

[16] [17]

−6.01(10) −6.29(6) −6.80(41) 49.60(10) 49.37(20) 67.46(10) 67.28(26) 67.58(7) 67.50(40) 52.45(21) 52.54(10) 52.52(5) 53(1) 75.17(10) 75.18(14) 75.48(17) 74.80(41)

[13] [16] [17] 70.95(100) 71(1) 68.48(50) 69(2) 68.21(50) 67(1) 32(2) 32.92(50) 32.06(83) 32.15(19) 30.55(100) 28(1) 29.62(50) 30.82(55)

[13] [17] [13] [14] [15] [17] [14] [15] [16] [17] [13] [14] [15] [17] (continued on next page)

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

Table 3 (continued) Electronic Configuration

Eo (cm−1 )

AExp

BExp

A

B

[1]3/2

78,415.247

60.21(34)

15.18(93)

60.38(10) 60.77(40) 60.47(10) 60.86(23) 61.31(85)

15.44(50) 15(2) 14.2(17) 16.32(75) 16.17(13)

[1]1/2

79,701.591

158.51(41)

5s2 5p4 (3 P2 )7p [3]7/2

75,194.056

19.04(59)

−35.71(73)

[3]5/2

75,191.337

22.75(39)

−19.11(96)

[2]5/2

74,965.635

24.56(33)

[2]3/2

75,049.514

[1]3/2

158.47(20) 159.27(73) 158.20(15) 158(1)

Refs.

[13] [14] [15] [16] [17] [13] [14] [16] [17]

18.91(5) 18.96(3) 18.94(9) 22.75(20) 22.37(14) 22.08(94)

−35(1) −34.47(62) −34.59(75) −19.86(100) −19.92(69) −19.68(24)

[13] [16] [17] [13] [16] [17]

−25.10(75)

24.73(20) 24.86(11) 24.97(16)

−23.42(100) −23.49(30) −23.53(16)

[13] [16] [17]

37.82(81)

−23.63(86)

75,621.427

27.85(49)

0.9(52)

38.07(10) 37.72(72) 27.76(5) 28.41(15) 27.58(17) 27.73(3) 27.78(62)

−23.6(10) −23.62(87) 0.41(50) 0(7) −1.23(50) 0.92(83) 1(1)

[13] [17] [13] [14] [15] [16] [17]

[1]1/2

75,303.065

64.99(44)

5s2 5p4 (3 P1 )7p [2]5/2 [1]3/2 [1]1/2

82,213.940 82,424.15 82,615.750

−6.04(75)

[0]1/2

81,506.800

7.84(46)

81,722.90

19.24(66)

−17.01(83)

78,844.303

19.18(35)

−26.76(93)

[3]5/2

78,854.747

24.58(16)

−14.38(44)

[2]3/2

78,815.440

40.78(35)

−17.13(91)

[2]5/2

78,732.231

25.80(7)

−25.95(33)

[1]3/2

79,224.656

36.89(41)

4.77(99)

[1]1/2

78,780.107

79.56(21)

5s2 5p4 (3 P2 )4f [5]11/2

77,362.128

[5]9/2 [4]9/2

77,362.802 77,306.559

14.74(35) 10.64(43)

13.21(78) 8.01(75)

[4]7/2 [3]7/2

77,307.280 77,313.459

9.22(27)

8.0(11)

5s2 5p4 (3 P0 )7p [1]3/2 5s2 5p4 (3 P2 )8p [3]7/2

65.07(5) 64.68(17) 65.37(6) 65.24(74) 28.69(98)

[13] [15] [16] [17]

−6.47(89) 18.91(33) 4.70(33) 4.98(46) 4.83(77) 7.65(12) 6.47(33) 8.64(35)

27(1) 30.0(33)

[17] [16] [15] [16] [17] [14] [16] [17]

18.76(100) 18.75(95) 24.96(17) 23.85(12) 23.51(25) 40.37(72) 40.40(13) 41.02(97) 26.05(19) 25.85(5) 36.56(20) 36.09(17) 36(1) 80.07(35) 79.24(17) 79.55(24) 79.05(5)

−24.5(50) −24(1) −19.95(67) −16.56(41) −16.54(32) −15(4) −15.93(65) −16(1) −26.09(67) −26.31(10) 4.32(200) 5.30(67) 5(1)

[13] [17] [15] [16] [17] [14] [16] [17] [16] [17] [13] [15] [17] [14] [15] [16] [17]

11.21(10)

−1.52(100)

[13]

14.03(100) 10.37(50) 10.71(43) 11.17(36) 13.0(75) 8.93(50) 10.51(24)

0.95(200) 7.89(100) 7.19(57) 7.40(96) 136.79(82) 9(2) 9.62(40)

[13] [13] [16] [17] [17] [13] [17] (continued on next page)

173

174

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179 Table 3 (continued) Electronic Configuration

Eo (cm−1 )

AExp

BExp

A

B

[3]5/2

77,307.333

11.44(76)

−2.3(25)

[2]5/2

77,359.585

−1.17(86)

20.4(13)

[2]3/2

77,356.636

[1]3/2

77,406.784

−21.51(4)

−4.53(42)

−5.0 10.70(49) 20(1) 21.58(67) 19.71(87) 2(1) 1.94(91) −4.78(10) −4(2) −4.77(8)

[1]1/2

77,404.362

−44.18(86)

10.7(10) 11.17(68) −0.3(10) 0.10(17) −0.77(92) 3.25(50) 5.05(50) −21.98(10) −21.50(42) −22.61(5) −43.49(10) −44(1)

[13] [17] [13] [15] [17] [13] [16] [13] [14] [17] [13] [17]

5s2 5p4 (3 P2 )5f [5]11/2 [5]9/2 [4]9/2 [4]7/2 [3]7/2

79,859.010 79,859.570 79,829.600 79,832.955 79,847.683

11.84(59)

−42.70(83)

14.28(47)

−5.34(56)

[3]5/2 [2]5/2

79,844.469 79,840.152

[2]3/2

79,834.910

9.47(24)

18.36(81)

[1]3/2

79,881.383

−15.41(33)

6.14(55)

−46.16(85) −27.35(52) 43(1) −3.93(47) 9.36(71) 9.40(88) 15.99(32) 12.44(200) 11.67(79) 9.74(98) 18(1) 16.7(17) 17.81(74) 17.64(74) 3(1) 2.56(47) 6.07(68)

[1]1/2 5s2 5p4 (3 P2 )6f [4]7/2 [3]7/2 [1]3/2 [1]1/2

79,881.733

11.51(70) 15.01(18) 11.07(89) 15(2) 7.47(9) 7.57(14) 9.98(32) 3.46(100) 3.39(33) 1.73(52) 8.75(18) 9.31(33) 9.13(3) 9.11(15) −21.74(23) −21.20(12) −15.24(27) 38.98(36)

[17] [17] [17] [17] [16] [17] [17] [13] [16] [17] [14] [15] [16] [17] [14] [16] [17] [14]

−1(4) 30(6) −6(5)

[0]½ 5s2 5p4 (3 P2 )9p [3]5/2 [2]5/2 [2]3/2 [1]3/2

81,506.80

13.29(31) 6.35(49) −20.96(92) −42.32(27) −40.09(51) 7.65(12)

[14] [14] [14] [14] [17] [14]

−20.48(83) −21(2) −25(4) 1(3) −0.63(67) 14(1)

[1]½ 5s2 5p4 (3 P2 )7f [3]5/2 [2]3/2 [1]3/2 5s2 5p4 (3 P2 )8f [4]7/2 [3]5/2 [2]5/2 5s2 5p4 (3 P2 )9f [3]5/2

80,720.85

23.72(27) 25.13(26) 38.57(85) 26.19(59) 27.45(17) 28.42(46) 68.57(17)

[15] [14] [14] [14] [15] [17] [14]

82,027.93 82,033.54 82,045.39

−0.87(23) −0.40(33) −9.55(30)

19.0(27) 19.4(33) −53(1)

[15] [15] [14]

82,560.08 82,561.34 82,568.80

12.07(33) 11.34(33) −0.57(33)

−9.2(27) 5(2) 9(2)

[15] [15] [15]

82,926.55 78,727.287 82,930.41

−0.17(33) 24.98(33) 30.40(88)

6.3(33) −24.1(17) −37(5)

[15] [15] [14]

[2]3/2

81,201.66 81,207.14 81,227.24 81,225.890

80,659.03 80,624.32 80,616.13 80,797.780

Refs.

∗

The numbers in parentheses denote the uncertainty on the level of one standard deviation in the units of the last digit of the value, e.g., 27.59(5) denotes 27.59 ± 0.05.

their corresponding energy levels. First column lists the derived line position (center-of-gravity) wavenumber values of all the 354 observed lines. The energy levels were classified using the Atomic Spectra Database of the National Institute of Standards and Technology (NIST) [20]. The spectral designation of a few observed lines could not be identified. Those lines have been listed as unclassified in Table 1. The center-of-gravity (C.G.) values were derived with uncertainties of a few times 10−3 cm−1 . Many spectra were recorded with various resolutions for the same spectral region. For each spectral set, the C.G. has been calculated for a specific hfs

structure and then the mean C.G. and standard deviation were estimated. The uncertainties derived from the standard deviation of C.G. wavenumbers presented in Table 1. In the studied IR spectral region, the calibration uncertainties were an order of magnitude smaller than the statistical uncertainties and hence are not included in Table 1. Figs. 4–10 present some representative observed and simulated spectra for atomic hfs structures in the region 1800– 60 0 0 cm−1 . The hyperfine structure for all the lines shown here is reported for the first time. The observed and simulated

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

175

Fig. 4. A well-resolved hfs splitting observed at 1853.746 cm-1 with 0.002 cm−1 resolution. This line was generated with an EDL discharge of 6 W power. Out of 12 hfs components, 10 were identified.

Fig. 5. A well-resolved hfs splitting observed at 2754.63 cm-1 with 0.002 cm−1 resolution. This line was generated with an EDL discharge of 6 W power. Out of 10 hfs components, 9 were clearly resolved.

Fig. 6. A well-resolved hfs structure for the line at 2943.387 cm-1 recorded with 0.002 cm−1 resolution in the EDL discharge of 6 W power. Out of 15 hfs components, 14 were clearly identified. Only one weak component at ‘c’ was not resolved.

176

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Fig. 7. A well-resolved hfs structure for the line at 3170.219 cm-1 recorded with 0.002 cm−1 resolution in the EDL discharge of 6 W power. Except a weak transition ‘e’, all 9 components were identified.

Fig. 8. An unresolved hfs structure for the line at 3860.932 cm-1 recorded with 0.002 cm−1 resolution in the EDL discharge of 6 W power.

spectra show a good match. Figs. 4–7 represent well-resolved hfs structures, whereas Figs. 8 and 9 display unresolved structures. Fig. 10 shows a transition at 5956.290 cm−1 with a flag-pattern structure. The procedure of hyperfine structure analysis and derivation of A and B constants using the programs HFSAB and WINHFS [21] have been described in ref. [17]. The same methodology has been applied here. Among 354 observed lines, hfs investigations were performed on 224 spectral lines with well-resolved hfs structures and large S/N ratio. Only center-of-gravity wavenumber values were derived for the remaining lines. Hfs analysis on 172 lines has been carried out for the first time. A total of 97 energy levels (53 even and 44 odd) were involved in the 224 well-resolved transitions. Hfs constants were derived for all 97 energy levels, out of which the constants of 5 levels are reported for the first time. Hfs constants were derived for 53 evenparity levels. Among these levels, 79,150.55, 80,693.945, 80,680.12 and 80,825.56 cm−1 were obtained for the first time. In case of odd levels, hfs constants were obtained for 44 levels, out of which

one level at 81,722.90 cm−1 was studied for the first time. Tables 2 and 3 provide a complete list of hfs constants of all the even and odd energy levels, respectively, known from the previous [13–17] and the present work. Uncertainties of A and B were derived as follows. For the levels involved in more than one transitions, A and B values were derived independently, and the mean values are given. For the levels involved in a single transition, repeated measurements were carried out to derive A and B constants and the mean values are given for each level. In both cases, standard deviations obtained were considered as their uncertainties. To minimize power and Doppler broadening effects on spectral lines, the EDL was operated under low microwave power along with reduced temperature. Surfatron cavity [22] and EDL were cooled with nitrogen gas, which is passed through a liquidnitrogen (LN2 ) bath. Consequently, the full width at half maximum (FWHM) of the spectral lines drastically reduced, and well-resolved hfs patterns were observed. Details of the experimental setup were discussed in our previous work [16].

C. Ashok, S.R. Vishwakarma and H. Bhatt et al. / Journal of Quantitative Spectroscopy & Radiative Transfer 235 (2019) 162–179

Fig. 9. An unresolved hfs structure for the line at 4949.045 cm-1 recorded with 0.01 cm−1 resolution in the EDL discharge of 14 W power.

Fig. 10. A partially resolved hfs structure for the line 5956.290 cm-1 recorded with 0.004 cm−1 resolution in the EDL discharge of 8 W power.

Fig. 11. A well-resolved hfs structure of the 2056 cm−1 spectral line. The table in the inset presents the line positions in cm−1 and respective FWHM values in MHz.

177

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Fig. 12. Unidentified lines observed in I I spectra. (a), (b), (c) and (d) show blended lines. (e) and (f) represent well-resolved hfs structure for most lines.

Fig. 11 shows the well resolved hfs structure of a line at 2056 cm−1 , which is the strongest line in the spectral region below 30 0 0 cm−1 . This was recorded at the instrumental resolution of 0.002 cm−1 , and the EDL was cooled and operated at 6 W microwave power. A table is also included in Fig. 11, to present the line positions (in cm−1 ) and their respective FWHM values (in MHz) measured under these experimental conditions. Most of the hfs components show the FWHM values less than 120 MHz. A few lines have been identified as unclassified transitions. For these transitions, center-of-gravity wavenumber values have been determined and are listed in Table 1. Fig. 12 represents some of the unclassified lines observed at 2500, 2548, 2574, 2580, 2719 and 3668 cm−1 . All these transition lines may be the blended lines, showing a complex structure. Fig. 12(a) and (b) are the lines for which only one transition has been identified for the highly complex structure, but the structure appears to be blended. Similarly, the complex and populated structure shown in Fig. 12(c) and (d) may also be the result of blended lines; in addition to showing some features of self-reversal in a few lines. All such blended lines have been marked with an asterisk (∗ ) in Table 1. The lines shown in Fig. 12(e) and (f) seem to show well-resolved hfs structures for most of the components, however their classification is not known.

4. Conclusion High resolution spectroscopic investigations were performed on neutral atomic iodine in the spectral region from 1800 to 60 0 0 cm−1 by employing a Fourier transform spectrometer. Electrodeless discharge lamps with CaF2 window were prepared and excited by using a surfatron microwave cavity to generate the plasma. A total of 354 spectral lines were observed in the entire spectral region. Center of gravity wavenumber values were determined for all observed lines. A special experimental set up has been applied to minimize the Doppler broadening of the spectral lines. An average FWHM of about 120 MHz (for well-resolved lines) has been achieved for a transition at 2056 cm−1 . Hfs investigations

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