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Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry logoLink to Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry
. 1969 Mar-Apr;73A(2):233–239. doi: 10.6028/jres.073A.021

A Table of Rotational Constants of Symmetric Top Molecules Giving Rise to Microwave Spectra*

Matthew S Lojko 1, Yardley Beers 2
PMCID: PMC6658462  PMID: 31929628

Abstract

This paper lists, in order of increasing value, the “B” rotational constants of most of the linear and symmetric top molecules which have been observed by microwave spectroscopy. Also are listed the microwave spectral lines which have been observed for the asymmetric tops water and formaldehyde. These data are useful for making a quick selection of a molecule which has a spectral line close to some previously selected frequency.

Keywords: Asymmetric, linear, and symmetric top molecules; “B” rotational constants; formaldehyde; microwave spectra; spectral lines; water


Nowadays there are a number of actual and potential situations in which one would like to select a molecule to have a spectral line close to some previously specified frequency. For one thing, the transitions of light linear or symmetric top molecules, which lie in almost but not exact harmonic relationship, are used to tune up millimeter wave spectrographs. For another, there is a great interest in devising experiments, many involving lasers, in which a spectral line, or one of the harmonics of its frequency, nearly coincides with a spectral line of another substance. In addition there might be practical applications, such as in a communications system, in which it may be desired to build a molecular frequency standard with its fundamental close to some previously chosen frequency.

As an aid to making such a selection, herewith in table 1 is presented, in order of increasing value, the “B” rotational constants of most of the linear and symmetric top molecules which are listed in “Microwave Spectral Tables,” National Bureau of Standards, Monograph 70.1 From the simple well-known formula given in eq (1) it is possible to get a very good approximation of the frequencies of nearly all of the rotational lines of these molecules. The frequency

f=2BJ, (1)

where J is any integer, which is the quantum number giving the total angular momentum (not including nuclear spin) of the upper state giving rise to the transition. In table 1, values of B are given for only one isotopic species of each molecule, generally the most abundant one. The values for other isotopic species may be easily determined from the fact that B is inversely proportional to the reduced mass of the molecule. Also listed in table 1 are the common names of the molecules to aid in referring to handbooks giving physical properties and to the catalogs of chemical companies.

Table 1. “BRotational constants of symmetric top and linear molecules.

B(MHz) Molecule name Isotopic speciesa
708.3579 Cesium Iodide Cs133I127
725.9 I-Bromo-Bicyclo(2,2,2)Octane C812H13Br79
729.8 Benzene Chromium Tricarbonyl C612H6Cr52(C12O16)3
788.0 Methyl Mercuric Iodide C12H3HghIb
817.510 Thallium Iodide TI205I127
891.69 l-Chloro-3,3-Dimethyl-l-Butyne (C12H3)3C12C12=C12Cl35
984.3166 Rubidium Iodide Rb85I127
996.4 Phosphorus Tribromide PbBr379
1081.343 Cesium Bromide Cs133Br79
1096.42 Trimethyliodosilane (C12H3)3Si28I127
1104.95 Indium Iodide In115I127
1142.86 Methyl Mercuric Bromide C12H3Hg198Br79
1247.61 Tribromomethane C12HBr379
1259.02 l-Iodopropyne H3C12C12≡C12I127
1259.25 Nickel Cyclopentadienyl Nitrosyl C512H5N14Ni58O16
1297.409 Thallium Bromide TI205Br79
1369.70 1,1,1-Trifluoro-2-Butyne C12H3C12C12C12F319
1402.64 Thiophosphoryl Chloride S32P31C335
1424.840 Rubidium Bromide Rb85Br79
1461.95 Trirnethylbromosilane (C12H3)3Si28Br79
1467.98 Cyclopentadienyl Thallium C512H5TI203
1497. Bismuth Trichloride Bi209Cl335
1516.018 Silyl Isothiocyanate Si28H3N14C12S32
1523.23 Trifluoroiodomethane C12F319I127
1549.98 Bromotrifluorosilane Si28F319Br79
1561.11 I-Bromopropyne H3C12C12≡C12Br79
1562. 2-lodo-2-Methylpropane (C12H3)3C12I127
1573.7 Trimethylamine-Trimethylborane (C12H3)3N14 · B11(C12H3)3
1584.122 Thiocarbonyl Telluride S32CI2Te122
1599.3 Methyltrichlorogermane C12H3GebCl335
1667.2 Trichloroacetonitrile C12Cl335C12N14
1670.14 Indium Bromide In115Br79
1706.86 Gallium Monoiodide Ga69I127
1750. Trifluoroborane-trimethylamine F319BbNb(C12H3)3
1753.9 Antimony Trichloride Sb121Cl335
1769.836 Methyltrichlorosilane C12H3Si28Cl335
1825.012 Potassium Iodide K39I127
2001.56 Thiocarbonyl Selenide S32C12Se82
2015.20 Phosphoryl Chloride P31O16Cl335
2035.741 Penta-l,3-Diyne H3C12C12≡C12C12≡C12H
2044.2 2-Bromo-2-Methylpropane (C12H3)3C12Br79
2065.73 2-Butynenitrile H3C12C12≡ C12C12N14
2077.48 Methyl Mercuric Chloride C12H3HG198CI35
2094.20 Rhenium Trioxychloride Re185O316Cl35
2098.06 Bromotrifluoromethane C12F319Br79
2147.2 Arsenic Trichloride As75Cl335
2161.208 Cesium Chloride Cs133CI35
2168.52 Chlorotrifluorogermane Ge70F319Cl35
2172.75 Trichlorogermane Ge70HCl335
2197.441 Trimethylchlorosilane (C12H3)3Si28CI35
2232.271 1-Chloropropyne C12H3C12 ≡ C12CI35
2326. Phosphorus Tricyanide Pb(CI2N’4)3
2372.6 1,1,1 -Trichloroethane C12H3C12Cl335
2431.4 Quinuclidine C712H13N14
2434.953 Potassium Bromide K39Br79
2438.57 Bromogermane Ge70H3Br79
2465.39 Trichlorofluoromethane C12Cl335F19
2472.489 Trichlorosilane Si28HCl335
2477.79 Chlorotrifluorosilane Si28F319Cl35
2481.99 Gallium Monobromide Ga69Br79
2617.1 Phosphorus Trichloride P31Cl335
2657.63 Thiophosphoryl Fluoride S32P31F319
2683.18 1,1-Dimethyl-3-Butyne (C12H3)3C12C12 ≡ C12H
2743.913 Thallium Chloride TI203CI35
2749.89 2,2-Dimethylpropanenitrile (C12H3)3C12C12N14
2767.414 Rubidium Chloride Rb85CI35
2877.93 3,3,3-Trifluoro-1-Propyne C12F319C12=C12H
2945.528 Trifluoroacetonitrile C12F319C12N14
3017.69 2-Chloro-2-Methylpropane (C12H3)3C12CI35
3215.52 lodosilane Si28H3l127
3225.578 Cyanogen Iodide I127C12N14
3257. Methyltrifluorogermane C12H3GebF319
3269.47 Indium Chloride In115CI35
3301.94 Trichloromethane C12HCl335
3335.56 Chlorotrifluoromethane C12F319Cl35
3411.00 Trimethylfluorosilane (C12H3)3Si28F19
3422.300 Iodine Monochloride I127CI35
3531.778 Sodium Iodide Na23II27
3566.801 Rhenium Trioxyfluoride Re185O316F19
3715.66 Methyltrifluorosilane C12H3Si28F319
3856.399 Potassium Chloride K39CI35
4095.786 Carbonyl Selenide O16C12Se74
4120.230 Cyanogen Bromide Br79C12N14
4129.106 Manganese Trioxyfluoride Mn55O316F19
4321.72 Bromosilane Si28H3Br79
4401.71 Chlorogermane Ge70H3CI35
4493.73 Gallium Monochloride Ga69CI35
4534.52 Sodium Bromide Na23Br79
4549.07 Propiolonitrile HC12 ≡ C12C12N14
4570.92 Bromine Monochloride Br79CI35
4594.262 Phosphoryl Fluoride P31O16F319
4636.24 Trifluorosulfur Nitride N14S32F319
4712.15 2·Fluoro·2·Methylpropane (C12H3)3C12F19
4724.98 Trimethylarsine (C12H3)3As75
4972.7 Silyl Cyanide H3Si28C12N14
5185.14 1,1,I-Trifluoroethane C12H3C12F319
5260.66 Perchlorylfluoride Cl35O316F19
5273.6 1,3,5-Trioxane O16*C12H2O16C12H2O16C12*H2
5345.15 Trimethylsilane (C12H3)3Si28H
5527.34 Cesium Fluoride Cs13F19
5684.24 Chloroacetylene HC12 ≡ C12CI35
5816.24 Trimethylphosphine (C12H3)3P31
5878.971 Arsenic Trifluoride As75F319
5970.831 Cyanogen Chloride Cl35C12N14
6081.480 Carbonyl Sulfide O16C12S32
6537.07 Sodium Chloride Na23CI35
6673.8 Chlorosilane Sj28H3CI35
6695.46 Thallium Fluoride TI203F19
6906.35 Methyltin C12H3Sn118H3
7208.049 Trifluorosilane Si28F319H
7501.30 Iodomethane C12H3I127
7789.45 2-Methylpropane (C12H3)3N14
7819.900 Phosphorus Trifluoride P31F319
8545.84 Propyne C12H3C12≡C12H
8710.65 Methylgermane C12H3Ge70H3
8720.86 Trimethylamine (C12H3)3N14
8979.94 Carbonyl Borane H3B10C12O16
9198.83 Acetonitrile C12H3C12N14
9568.20 Bromomethane C12H3Br79
9706.22 Fluoroacetylene HC12≡C12F19
10052.88 Methyl Isocyanide C12H3N14C12
10348.74 Trifluoromethane C12HF319
10554.20 Cyanogen Fluoride F’9C12NI4
10680.96 Nitrogen Trifluoride N14F319
10706.9 Bromine Monofluoride Br79F19
10968.96 Methylsilane C12H3Si28H3
12561.64 Nitrous Oxide N214O16
13292.84 Chloromethane C12H3C135
14327.9 Fluorosilane Si28H3F19
15381.99 Lithium Iodide Li6I127
15483.69 Fluorine Chloride F19CI35
19162.32 Lithium Bromide Li6Br81
24584.35 Carbon Monosulfide C12s32
25530.59 Fluoromethane C12H3F19
43100.5 Oxygen O216
44315.99 Hydrocyanic Acid HC12N14
51109.51 Nitric Oxide N14O16
57898.568 Carbon Monoxide C12O16
88031.92 Stibine Sb121H3
112468.5 Arsine As75H3
128600 Hydrogen Bromide DBr79
133478.3 Phosphine P31H3
163340.1 Hydrogen Chloride DCI35
195229.1 Hydrogen Iodide HI127
298000 Ammonia N14H3
a

The superscript b means that the particular isotope was not specified.

The values of B given in table 1 were obtained from the same punched computer cards which served as the basis of the “Microwave Spectral Tables.” A program was written for selecting the values in accordance with the present philosophy, arranging the values in ascending order, and printing out the result. In this tabulation, it has not been practical to distinguish between ground vibrational state (Bo) and equilibrium state (Be) values. In most cases, however, for polyatomic molecules the values given pertain to the ground vibrational state while for diatomic molecules they pertain to the equilibrium state. However, the difference between values of these quantities for the same molecule is probably smaller than the errors associated with eq (1) which result from the neglect of such effects as centrifugal distortion and hyperfine effects.

Accordingly, it is appropriate to give some general discussion of the tables. The present series of volumes are based upon a thorough search of the literature of microwave spectroscopy. The cut-off date of the search differs slightly from volume to volume but is approximately 1961 for all of them. In addition, through the cooperation of numerous investigators, much unpublished data and data published in sources not widely available have been included. In a number of cases where important data after the official cut-off date happened to be conveniently available, they were included, but inclusion of post-cut-off data was determined by convenience and nothing else. A critical selection was made, and the selected data on frequencies and molecular constants were transcribed upon punched cards. The cards were checked against the original sources. Except for a few nonstandard situations, all final print-out was made direct from the cards by use of suitable programs. The present series of volumes were carried out in accordance with a plan developed by Paul W. Wacker. It received sponsorship of the Office of Standard Reference Data of the National Bureau of Standards when it became established. It is likely that in due time supplements to the present series will be published under sponsorship of the Office.

Volume V, which lists the measured frequencies of spectral lines in order of frequency, is also useful in giving direct answers to questions of the type described in the opening paragraph above. Indeed most of the time it may be more useful than table 1 and eq (1). However, the present material is useful in providing some answers not contained in Volume V, and therefore availability of the present material is highly desirable. One reason is that Volume V contains only lines that have actually been observed and measured accurately. However, there exist many lines which are observable but which have not been observed, and there are others which have been observed but not measured accurately and not published. In addition, Volume V contains very few entries above 300 GHz and none above 500 GHz. At the same time, the development of submillimeter lasers has stimulated a great interest in the frequencies of spectral lines up to a few thousand megahertz. The material given here can be used to give good approximations of the frequencies of many spectral lines which are involved in either of these two categories. Once eq (1) has been used to select a molecular transition, the frequency may be computed more exactly by including such effects as centrifugal distortion and hyperfine interactions by methods contained in textbooks but beyond the scope of this paper.

Of course, there are molecular transitions other than the rotational ones of symmetric top molecules that can serve the purposes alluded to in the introductory paragraph. The well known inversion spectrum of ammonia has been used for this purpose. The frequencies of the lines are tabulated in Volume V and elsewhere. The lines of asymmetric tops may be used too, if they are listed in Volume V or known by some other means. However, the calculation of their frequencies from molecular data cannot be done in closed form, and even rough estimates can sometimes be very laborious. Two of these molecules, water and formaldehyde, deserve special mention because samples are easy to obtain, and the lines from them are very strong and distributed widely over the spectrum. For convenience, the listings of spectral lines of these molecules, contained in Volume IV of NBS Monograph 70, are reprinted here in tables 2 and 3 respectively.

Table 2. Microwave spectral lines of water.

The Rotational Quantum Numbers are, respectively, J, K−1, and K+1 upper state followed by J, K−1, and K+1 of the lower state.

All transitions pertain to ground vibrational state.

Isotopic species Rotational quantum Nos. Hyperfine Frequency MHz Ace.
± MHz
F1 F′ F1 F
H3O16 3, 1, 3 ←2, 2, 0 183 311.30 .30
6, 1, 6 ←5, 2, 3 22 235.22 .05
HDOl6 1, 1, 0 ←1, 1, 1 80 578.15
2, 1, 1 ← 2, 1, 2 241 561.3
2, 2, 1 ← 2, 2, 0 1 3/2 2 5/2 10 278.0796 .001
2, 2, 1←2, 2, 0 3 5/2 3 7/2 10 278.1365 .001
2, 2, 1 ←2, 2, 0 1 1/2 1 3/2 10 278.1681 .001
2, 2, 1 2, 2, 0 3 5/2 1 3/2 10 278.2255 .001
2, 2, 1←2, 2, 0 10 278.2455 .001
2, 2, 1 ←2, 2, 0 1 3/2 3 5/2 10 278.2643 .001
2, 2, 1 ← 2, 2, 0 1 3/2 1 1/2 10 278.3234 .001
2, 2, 1 ← 2, 2, 0 3 7/2 3 5/2 10 278.3554 .001
2, 2, 1←2, 2, 0 2 5/2 1 3/2 10 278.4126 .001
3, 2, 1 ←3, 2, 2 50 236.30
3, 3, 0←3, 3, 1 3 5/2 2 3/2 824.4754 .002
3, 3, 0← 3, 3, 1 4 9/2 4 7/2 824.5074 .002
3, 3, 0 ←3, 3, 1 3 5/2 4 7/2 824.5247 .002
3, 3, 0←3, 3, 1 3 7/2 3 5/2 824.5488 .002
3, 3, 0← 3, 3, 1 3 7/2 4 9/2 824.5685 .002
3, 3, 0←3, 3, 1 2 5/2 4 7/2 824.6042 .002
3, 3, 0←3, 3, 1 824.6706 .002
3, 3, 0 ←3, 3, 1 2 5/2 4 7/2 824.7419 .002
3, 3. 0←3, 3. 1 3 7/2 4 9/2 824.7730 .002
3, 3, 03, 3, 1 3 7/2 3 5/2 824.7904 .002
3, 3, 0←3, 3, 1 3 5/2 4 7/2 824.8136 .002
3, 3, 0 ← 3. 3, 1 4 9/2 4 7/2 824.8341 .002
3, 3,0←3, 3, 1 3 5/2 2 3/2 824.8637 .002
3, 2, 1←4, 1, 4 20 460.40
4, 2, 24, 2, 3 143 727.2
4, 3, 1 4, 3, 2 5 702.78
5, 0, 5 ←4, 2, 2 2 887.4 .1
5, 1, 5 ←4, 2, 2 120 778.2
5, 3, 2 ← 5, 3, 3 22 307.67 .05
5, 4, 1 ← 5, 4, 2 5 11/2 5 9/2 486.266 .002
5, 4, 1← 5, 4, 2 5 11/2 4 9/2 486.450 .002
5, 4, 1 ← 5, 4, 2 5 11/2 6 13/2 486.487 .002
5, 4, 1 ← 5, 4, 2 486.528 .002
5, 4, 1 5, 4, 2 5 11/2 6 13/2 486.569 .002
5, 4, 1 ← 5, 4, 2 5 11/2 4 9/2 486.606 .002
6, 1, 6 ← 5, 2, 3 138 530.4
6, 4, 2 ← 6, 4, 3 2 394.56 .05
7, 1, 7 ← 6, 2, 4 26 880.38 .05
7, 4, 3 ← 7, 4, 4 8 577.7 .1
8, 4, 4 ← 8, 4, 5 24 884.77 .05
9, 5, 4 ← 9, 5, 5 3 044.71 .10
1O, 5, 5←10, 5, 6 8 836.95 .1
11, 5, 6←11, 5, 7 22 581.1 .2
12, 6, 6←12, 6, 7 2 961. 1.
D2O16 3, 1, 3 ← 2, 2, 0 7/2 3 5/2 2 10 919.301 .001
3, 1, 3 ← 2, 2, 0 9/2 5 7/2 4 10 919.357 .001
3, 1, 3 ← 2, 2, 0 5/2 4 3/2 3 10 919.521 .001
3, 1, 3 ← 2, 2, 0 9/2 3 7/2 2 10 919.603 .001
4, 2, 3 ← 3, 3, 0 43 414.57
4, 4, 0 ← 5, 3, 3 55 482.32
4, 4, 1 ← 5, 3, 2 10 947.13 .05
6, 1, 6 ← 5, 2, 3 90 916.8
HDO17 2, 2, 0 ← 2, 2, 1 10 374.56
3, , ← 2, , 23 374.4 .05
3, , ← 2, , 23 481.6 .05
3, , ← 2, , 23 585.6 .05
3, , ← 2, , 23 646.3 .05
3, , ← 2, , 24 256.0 .05
3, , ← 2, , 24 280.5 .05
3, , ← 2, , 24 384.9 .5
3, , ← 2, , 24 472.6 .5
3, , ← 2, , 24 528.8 .5

Table 3. Microwave spectral lines of formaldehyde.

The Rotational Quantum Numbers are, respectively, J, K−1, and K+1 upper state followed by J, K−1, and K+1 of the lower state.

All transitions pertain to ground vibrational state.

Isotopic species Rotational quantum Nos. Hyperfine Frequency MHz Ace. ±MHz
F1 F’ F1 F
HC12HO16 1, 0, 1← 0, 0, 0
1, 1, 0← 1, 1, 1
2, 0, 2 1, 0, 1
2, 1, 1← 1, 1, 0
2, 1, 2← 1, 1, 1
72 838.14
4 829.73
145 603.1
150 498.2
140 839.3
.01
.73
.75
.70
2, 1, 1← 2, 1, 2
3, 0, 3← 2, 0, 2
3, 1, 2← 2, 1, 1
3, 1, 3← 2, 1, 2
3, 2, 0← 2, 2, 0
14 488.65
218 221.6
225 698.2
211 210.6
218 759.4
1.1
1.1
1.1
1.1
3, 2, 2← 2, 2, 1
3, 1, 2← 3, I, 3
3, 2, 1 3, 2, 2
4, 1, 3← 4, 1, 4
4, 2, 2← 4, 2, 3
218 475.1
28 974.85
355.586 48
284.60 1
065.85
1.1
.005
.02
5, 1, 4← 5, 1, 5
6, 2, 4← 6, 2, 5
7, 2, 5← 7, 2, 6
8, 2, 6← 8, 2, 7
8, 3, 5← 8, 3, 6
72 409.35
4 954.76 8
884.87 14
726.74
301.10
.01
.01
9, 2, 7← 9, 2, 8
9, 3, 6← 9, 3, 7
11, 2, 9←11, 2,10
12, 3, 9←12, 3,10
13, 3,10←13, 3,11
22 965.71
601.07 48
612.70 3
225.58 5
136.58
.005
.1
.01
.01
14, 3,11 ←14, 3,12
15, 3,12 ←15, 3,13
16, 3,13←16, 3,14
17, 3,14 ←17, 3,15
19, 3,16←19, 3,17
7 892.03
11 753.13
17 027.60
24 068.31
45 063.10
.1
20, 4,16 ← 20, 4,17
21, 4,17 ← 21, 4,18
22, 4,18 ← 22, 4,19
23, 4,19 ← 23, 4,20
24, 4,20 ← 24, 4,21
3 518.85 5
138.57
7 362.60
10 366.51 14
361.54
.5
.5
25, 4,21 ← 25, 4,22
26, 4,22 ← 26, 4,23
28, 4,24 ← 28, 4,25
31, 5,26 ← 31, 5,27
19 595.23
26 358.82
45 835.58
7 833.20
1, 1, 0 ← 1, 1, 1
2, 1, 1 ← 2, 1, 2
3, 1, 2 ← 3. 1, 3
4, 1, 3 ← 4, 1, 4
7, 2, 5 ← 7. 2, 6
4 593.26
13 778.86
27 555.73
45 920.08
8 012.56
.5
.5
9, 2, 7 ← 9, 2, 8
14, 3,11 ← 14, 3,12
16, 3,13 ← 16, 3,14
17, 3,14 ← 17, 3,15
18, 3,15 ← 18, 3,16
20 736.30 6
752.31
14 592.44
20 649.30
28.582.40
.5
HC12HO18 1, 1, 0 ← 1, 1, 1 4 388.85 .5
DC12D016 1, 1, 0 ← 1, 1, 1
2, 1, 1 ← 2, 1, 2
4, 2, 2 ← 4, 2, 3
5, 2, 3 ← 5, 2, 4
6, 2, 4 ← 6, 2, 5
6 096.10
18 287.90
3 687.28
8 519.10
16 759.64
.02
.04
8, 3, 5 ← 8, 3, 6
9, 3, 6 ← 9, 3, 7
10, 3, 7 ←10, 3, 8
13, 4, 9 ← 13, 4,10
14, 4,10 ← 14, 4,11
2 850.62
5 636.98
10 304.64
3 079.48
5 461.54
.03
.03
15, 4,11 ← 15, 4,12
16, 4,12 ← 16, 4,13
19, 5,14 ← 19, 5,15
9 259.88
15 080.34
4 508.39
.04
HC12D016 1, 1, 0 ← 1, 1, 1
2, 1, 1 ← 2, 1, 2
3, 2, 1 ← 3, 2, 2
5, 2, 3 ← 5, 2, 4
6, 2, 4 ← 6, 2, 5
5 346.64
16 038.06
644.893
4 489.08
8 922.59
.03
.005
.03
7, 2, 5 ← 7, 2, 6
10, 3, 7 ← 10, 3, 8
ll, 3, 8 ← 1l, 3, 9
12, 3, 9 ← 12, 3,10
13, 3,10 ← 13, 3,1l
15 907.38
3 283.09
5 702.6
9 412.51
14 873.02
.03
16, 4,12 ← 16, 4,13
17, 4,13 ← 17, 4,14
18, 4,14 ← 18, 4,15
19, 4,15 ← 19, 4,16
23, 5,18 ← 23, 5,19
2 946.67
4 713.90
7 322.35
11 074.30
3 330.66
.03
.04
24, 5,19 ← 24, 5,20 5 018.25
HC12D016 1, 1, 0 ← 1, 1, 1 5 156.19 .10

Footnotes

*

Contribution of National Bureau of Standards and Environmental Science Services Administration, not subject to copyright.

1

These Tables may be obtained through the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402.

The following volumes have been published:

Volume I: Diatomic Molecules, by P. F. Wacker, M. Mizushima, J. D. Petersen, and J. R. Ballard, December 15, 1964.

Volume II: Line Strengths of Asymmetric Rotors, by P. F. Wacker and M. R. Pratto, December 15, 1964.

Volume IV: Polyatomic Molecules Without Internal Rotation, M. S. Cord, J. D. Petersen, M. S. Lojko, and R. H. Haas, October 1968.

Volume V: Spectral Line Listing, by M. S. Cord, M. S. Lojko, and J. D. Petersen, June 1968.

Publication of the remaining volume is expected shortly:

Volume III: Polyatomic Molecules With Internal Rotation, P. F. Wacker, M. S. Cord, D. G. Burkhard, J. D. Petersen, and R. F. Kukol.

Contributor Information

Matthew S. Lojko, Environmental Science Services Administration, Boulder, Colorado 80302

Yardley Beers, National Bureau of Standards, Boulder Colorado 80302.


Articles from Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry are provided here courtesy of National Institute of Standards and Technology

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