High-resolution Fourier spectrometry of 14N2 infrared emission spectrum: Analysis of the w1Δu-a1Πg system

JOURNAL

OF

MOLECULAR

SPECTROSCOPY

91, 238-242 (1982)

High-Resolution Fourier Spectrometry of 14N2Infrared Emission Spectrum: Analysis of the wlA,-alI& System F. Roux, Laboratoire

C. EFFANTIN, AND J. D'INCAN

de SpectromPtrie Ionique et Mokulaire (Associi au CNRS), UniversitP de Lyon I 43, Boulevard du II Novembre 1918, 69622 Villeurbanne, France

AND

J. Laboratoire

VERGES

AimP Cotton, CNRS II, Brit. 505-Campus

d’orsay,

91405 Orsay, France

The study by high-resolution Fourier Spectrometry of the wlA,-alI& system of N, allowed us to measure the absolute wavenumbers of rotational lines in the O-O, l-0, 2- 1, 3-2 bands with a precision of 3.10m3cm-‘. Rotational analysis gave us very precise rotational parameters. INTRODUCTION

Infrared Fourier spectrometry of a discharge in a mixture of N2 and Ne allowed us to observe transitions between excited singlet levels of the nitrogen molecule. In these conditions, the wlAU-all& system occurs, with a good signal-to-noise ratio in the near infrared between 3500 and 4500 cm-l, while the intensity of the a’&,-a’ ‘Z; system is very weak. The w and a states are well known through the transitions w c X and a -+ X, but only a few lines of the O-O band in the w + a system have previously been observed by MC Farlane (I, 2) in an oscillating optical maser. We measured with high precision absolute wavenumbers of numerous lines in four bands of the system w + a. DESCRIPTION

OF THE SPECTRUM

The transitions studied in this paper are the (O-O), (1 -O), (2- I), and (3-2) bands of the w’A,-alI& system. They are degraded toward lower wavenumbers. The rotational structure consists of three branches P, Q, R without any intensity alternation for J values lower than 14. At higher J, where the A-type doubling in the ‘II state is resolved, three pairs of branches occur with the two close-lying branches showing opposite intensity alternation.

0022-2852/82/010238-05.$02.00/O Copyright

8 1982 by Academic

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of reproduction

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in any form reserved.

238

ANALYSIS

OF THE w’A,-a’&,

239

SYSTEM OF N,

TABLE I Measured and Calculated Wavenumbers (cm-‘) of Lines in the (O-O) and (1-O) Bands of the wLAu-a*&, System of N, .I

P

I 2 3 4 5 6 7 8 9 10 II 12 13 14 15 16 I7 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

ee

2733.0265 2728.8553 2724.4442 2719.7968 2714.9074 2709.7862 2704.4212 2692.9808 2680.5919

Rff

J I 2 3 4

Qfe (0-O)

(0-O)

-2740.6540 -2736.9599 -.0004 .0003 -.0003 .0013 -.0009 .0032 .0013 -2698.8192 -.0004 -2686.9060 -.0021 -2674.0453 -2667.2604 -2660.2394 -2652.9827 -2645.4905 -2637.7632 -2629.8011 -2621.6045 -2613.1738 -2604.5094 -2595.6114 -2506.4804 -2577.1168 -2567.5209 -2557.6930 -2547.6337 -2537.3434 -2526.8224 -2516.0712 -2505.0902 -2493.8799

.0014 .0014 .0003 .0006

5 6

2761.5855 2763.1228

.0006 -.0002

7 8 9 10 II

2764.4213 2765.4769 2766.2967

.0003 -.0022 -.0003 -2766.87‘7 -.0011 .0015 .0012 .001* .0012 -.OOOl .0003 -.0002 -.0006 -.wo3

12

13 14 15 16 17 I8 19 20 21

22 23 24 25 26 27 28 29 30 31 32 33 34 35

2720.6574 2722. ,991 2718.6133 2714.7093 2710.7268 2706.4260

P

(0-O)

2753.0355 2755.5328 2757.7893 2759.8074

2767.2111 2767.3110 2767.1677 2766.7850 2766.1609 2765.2958 2764.1922 2762.8475 2761.2627 2759.4384 2757.3741 2755.0683 2752.5249 2749.7431 2746.7149

2746.6054 2745.8865 2744.9289 2743.7342 2742.2957 2740.6204 2738.7068 2736.5564 2734.1606

.woo

-.0012 .0001 .0026 -.0014 -2743.4525 -2739.9491 -2736.2063 -2732.2242 -2728.0030 -2723.5428 -2718.8437 -2713.9060 -2708.7298 -2703.3152

ee

4259.5487 4254.7054 4249.5883 4244.2048 4238.5448 4226.4212 4219.9518 4213.2152 4206.2072 4198.9320 4191.3884 4183.5758 4175.4943 4167.1462 4158.5341 4140.4922 4131.0812 ‘121.3976 4111.4495 4101.2350 4090.7553 4080.0117 4069.0039 4046.1970 4022.3367

R

-2747.0851 -.ooo* -.0015 -.0014 .OOlO -.0012 -.OOLO .wo2 .0036 .0007 -2731.5281 -.0002 -2725.5483 -.0013 -.ooo* -.oOO, .M02 .WO, -2701.8873 -2697.llll -2692.0974 -2686.8465 -2681.3585 -2675.6337 -2669.6723 -2663.4746 -2657.0408 -2650.3710 -2643.4658 -2636.3251 -2628.9495 -2621.3391 -2613.4943 -2605.4154 -2597.1027

ee(0-O)

2753.0355 2755.5328 2757.7893 2759.8074 2761.5855 2763.1228 2764.4213 2765.4769 2766.2967 2766.8687 2767.2973 2767.1538 2766.7672 2766.1409 2765.2746 2764.1697 2762.8223 2761.2351 2759.4067 2757.3379 2755.0315 2752.4842 2749.6945

Q,,

(I-0)

-4276.2160 -4272.4566 -4268.4254 -4264.1228 -.wo2 .0016 .wo5 .0037 .oo,o -4232.6163 .0025 .0005 .0009 -.COO8 -.coo7 -.m2 -.cQo3 -.oo, 1 -.wo7 .0033 -4149.6475 -.cQ51 -.0002 .0004

woo

-.0005

-.&JO2 .ooo, -4057.7319 .0006 -4034.3980 -.0003 -4010.0139

4282.1021 4281.2858 4280.1973 4278.8378 4277.2052 4275.3029 4273.1257 4270.6803 4267.9580 4261.7034 4258.1670 4254.3627 4250.2834 4245.9380 4241.3195 4236.4301 4231.2656 4225.8408 4220.1402 4214.1711 4207.9299 4201.4208 4194.6409 4187.5927 4180.2743 4172.6900 4164.8382 4156.7145 4148.3290 4130.7393 4121.5490 4112.0902

Pff

Q ef

(0-O)

-.oo,* -.0015 -.w21 -.OOll -.0002 .oooo .0016 .0005 .0039 -.0001 -2767.2045 -.0025 -.0009 -.0019 -.0022 -.0021 -.0002 -.wo4 -.0001 -.0007 -.OO,‘

2733.0265 2728.8553 2724.4442 2719.7968

2714.9074 2709.7862 2704.4212 2698.8277

-2740.6511 -2736.95i6 .0013 .0012 -.0004 .oooo -.0035 -.oo,o -.0046 .ooo* -2692.9908 -2686.9178 -2680.6081 -2674.0620 -2667.2797 -2660.2615 -2653.0077 -2645.5186 -2637.7946 -2629.8359 -2621.6428 -2613.2158 -2604.5552 -2595.6612 -2506.5344 -2577.1750 -ii67;58;4 -2557.7601 -2547.7055 -2537.4199 -2526.9038 -2516.1576 -2505.1818 -2493.9768

.wo3 .0013 -.0002 '746.6665 IG743.3986 -2739.8909 -2736.1438 -2732.1572 -2727.9313 -2723.4663 -2718.7623 -2713.8195 -2708.6382 -2703.2184

2746.6054 2745.8865

2744.9289 2743.7341 2742.2967 2740.6226 2738.7068 2736.5565 2734.1656 2731.5350 2728.6696 2725.5637 2722.2160 2718.6317 2714.8109 2710.7484 2706.4514 2701.9163

ee(l-0)

R

0-O) -4282.6471 -.ow* -.0007 -.&lo* .OoO, -.ooo, .0020 .oo,o .0036 .oo,o -4264.9657 .0006 -.0016 -.0003 -.002v -.OW6 -.0006 -.0007 -.0054

4288.5327 4290.9310 4293.0588 4294.912, 4296.4942 4297.8021 4298.8394 4299.6008 4300.0934 4300.3074 4299.9210 4299.3155 4298.4409 4297.2920 4295.8693 4294.1809 4292.2059 4289.9648 4287.4499 4284.6625 4281.6021 4278.2706 4274.6625 4270.7840 4266.6373 4262.2108 4257.5139 4252.5455 4247.3079 4241.7919 4236.0046 4229.9555 4223.6257 4217.0283

CQOO

-.0002 .0011 .OOO! .0007 -.OoOl -.OCO1 -.0014 .WOI

.0024

.0009

.0054 -4139.6660 -.001* -.0003 -.0007

Pff

-.0013 -.oo,* -.0004 -.ooov .0002 -.0003 .0016 .0005 .0036 .0011 -4 300.2498 .0009

-.001* -.coo5 -.0003 -.ooo* .0062 -.0004 .oooo -.0004 -.oco4 -.0004 .0013 -.000* -.0007 .003* .0010 .OQOl -.OOOl .0026 -.0012 -.0045 .0021 -.0007

.0003

4259.5407 4254.7054 4249.5883 4244.2048 4230.5449 4232.6226 4219.9630 4213.2256 4206.2254 4198.9527 4191.4116 4183.6014 4175.5234 4167.1624 4158.5657 4149.6856 4140.5385 4131.1268 4121.4489 4111.5031 4101.2911 4090.8184 4080.0807 4069.0756

J

(0-O) -2747.0819 .oo*o .0009 .0003 .0017 -.0004 -.ooo, -.0025

-.ooos -.0002 -.ooo* .0024 .0036 .0015 .OOlO .0022 .0003 .0005 .0009 -2697.1424 -2692.132, -2686.8848 -2681.4005 -2675.6795 -2669.7221 -2663.5285 -2657.0989 -2650.4336 -2643.5328 -2636.3969 -2629.0260 -2621.4205 -2613.5808 -2605.5070 -2597.1995

1 2 4 5 6 7 8 9 10 II 12 13 14 15 16 17 I8

19

20 2, 22 23 24 25 26 27 28 29 30 31 32 33 34 35

J

(I-0)

-4276.2131 -4272.4542 -4268.4238 -4264.1220 -.0004 .0002 -.0022 -.0005 -.0048 -.0014 -4226.4204 -.OOOL -.oo** .WO8 .WO8 .0009 .0@33 -.ooo, .0042 .0002 -.0002 -.Ocw* .0003 .0013 0001 -.0021 , 0000 ,001,

.oooo -4057.8084 -4046.2778 -4034.4844 -4022.4286 -4010.1107

2 3

6

8 9 10

20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

240

ROUX ET AL. TABLE

.J

I 2 3 4 5 6 7 8 9 10 II 12

ii

14 I5 16 1, 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

.I

Qef (l-0)

4282.102, 4281.2858 4280.1973 4278.8378 4277.2052 4275.;02* 4273.1257 4270.6803 4267.9580 4264.9729 4258.1803 4254.3763 4250.3034 4245.9584 4241.3426 4236.4558 4231.2992 4225.8,26 4220.1753 4214.2095 4207.9714 4201.4694 4194.6906 4187.6462 4180.3322 4172.7514 4164.9019 4156.7853 4148.3944 4139.7473 4130.8299 4121.6418 4112.188,

Pff I 2 3 4 5 6

7

8 9 10 II 12 13 14 15 16

1,

18 19 20 2, 22 23 24 25 26 2, 28 29 30 :: 33 34 35

Rff

-4202.6439 .0021 .OO,b .ooov .OOlO -.0002 .OOOb -.oo,, -.OOOb -.0048 -.0004 -4261.7125 -.OQOl -.OOOV .0004

.0005 .0005

.0000 .0002 .0005 .0002 .0012 -.0004 .0035 -.0002 -.0005 -.OO,, -.0011 -.OOlO -.WOI -.oo5, -.ooo, .0023

.oo,v .OOIO .0020 . 0008

4296.4942

.oo,o

4297.8021 4298.8394 4299.6001 4300.0934 4300.3074 4300.2563 4299.3289 4298.4548 4297.3098 4295.8898 4294.1935 4292.2314 4289.9928 4287.481, 4284.6974 4281.6404 42,8.3125 4274.7091 4270.8344 4266.6882 ‘257.5766 4252.6120

.0006

3938.8290 3928.2193 3917.3451

4127.8408 4127.0349 4125.9597 4124.6171 4123.0041 4121.1248 4118.9742 4116.5561 4113.8707 4110.9213 4107.6938 4104.2131 4100.4561 4096.4328 4092,141, 4087.5824 4002.7549 4077.6633 4072.3035 4066.6771 4060.7842 ‘054.6266 4048.201, 4041.5103 4034.5495 4027.3331 4019.8472 4012.0967

3906.2222

-3894.8326 .0011

3995.8032

3996.9758 3987.9458 39,8.6442 3969.0839

-3883.1849 -3871.2783 -3859.1134

-.0004

ee(2-I)

4118.3017 4114.3170 4110.0650 4105.5419 4100.7561

.0003

-.002x -.0006 -.0048 -.0012 -4299.9298 -.0002 -.*002 .0009 .0005 -.0033 ,000, -.0001 .oooo -.0002 -.0004 ,000 .0000 -.ooo,

4090.3770 4084.7839 4078.9305 4072.8006 4066.4060 4059.7494 ‘052,827, 4045.6375 4038.1852 4030.4635 4022.4802 4014.2318 4005.7176 3996.9428 3978.6012 3969.03‘2

.0008

-4262.2680 .0002 -.ooo, -4247.3771 -4241.8696 -4236.0905 -4230.0399 -4223.7180 -4217.1249

Qef (2-I)

-4122.0178 .ooo2 .0001 .0005 -.002, .oooi .00‘4 -.ooo, -.0042 -.0012 .0038 -.0004 -.0004 .0042 0009 .0004 .woo -.0010 -.0008 -4005.7522 -.oo35 .002, .0001 .0015 -3959.2586 -3949.1730 .0028 .oo,o -.0046

4118.3017 4114.3170 4110.0649 4105.5419 4100.7561 4095.7049 4090.3777 4084.7839 4078.9305 4072.8125 4066.4190 4059.7637 4052.8472 4045.6574 4038.2052 4030.4882 4022.5060 4014.2608

P

4288.5327 4290.9310 4293.0588 4294.9121

.ooov

(2-I)

(I-0)

I-Continued

-4128.376, .0014 .0014 .0006 .oo*o -.0005 .0002 -.0021 -.C036 -.0043 -.0008 -.0074 .0006 .0001 .0009 .w12 .ooo* -.ooo, .0005 .0004 .0003 .oooo .w12 .0004 .owc -.co48 -.0001 .OOoo .0002 -4004.0813 .WII -3987.2589 -3978.4523 -3969.3824 -3960.0497

Rff 4134.1999 4136.5730 4138.6771 4140.5114 4142.0783 4143.3730 4144.4008 4145.1564 41‘5.6461 4145.8619 4145.8139 4144.9051 4144.0451 4142.9177 4141.5181 4139.8527 4137.9111 4135.7036 4133.2276 4130.4813 4127.4656 4124.181, 4120.6326 4112.7141 4108.3533 4098.8249 4093.6605 4088.2321

-4122.0207 -.0022 -.OOll -.0004 -.0022 .ca11 -4095.6983 .0028 .0010 .0058 .0007 -.0025 -.0016 .0001 -.OO,I .0011 -.0012 -.0003 -.OOOl -.0017 -.oooo -3987.9030 .*011 -.0004 -3959.2067 -3949.1169 -3938.7657 -3928.1533 -3917.2802 -3906.1469 -3894.,x38 -3883.1013 -3871.1898 -3859.0199

(2-I) .0016 .0015 .0014 .0007 .0017 -.0002 .0004 -.0018 -.0005 -.0035 -.ooo* -4145.4943 .0007 .0002 .0018 .0008 .0036 -.0002 -.0005 .oooo -.0003 -.0008 -.0003 .0040 -4116.8060 -.0005 -.0010 -4103.7255 -.0032 -.0019 .0036 -4082.5263 -4076.5564 -4070.3187 -4063.8135

-

Q,,

4127.8408 4127.0349 4125.9597 4124.6171 4123.0041 4121.1248 4118.9742 4116.5562 4113.870, 4110.9213 4107.6934 4104.2003 4100.4428 4096.4156 4092.1218 4087.5602 4082.7315 4077.6366 4072.2731 4066.6435 4060.7475 4048.1569 4041.4628 4034.502,

P

(2-I) -4128.3799 -.w15 -.oo,, -.0012 .0000 -.0006 .0012 .ooo, .'XlOl .ooov ,006, .0010 -.0014 -.WOZ -.0009 -.ooo, -.0008 -.ooo, .0004 -.0003 -.0003 -.0002 -4054.5853 .*oo, .0004 .0002 -4027.2772 -4019.7868 -4012.0316 -4004.0119 -3995.7280 -3987.1801 -3978.3687 -3969.2939 -3959.9562

ee(3-2)

3964.7026 3960.5000 3956.0374 3951.3010 3946.3057 3941.0489 3935.5239 3923.6901 3910.7958 3903.9646 3896.8629 3889.5021 3881.8843 3873.9965 3865.853, 3857.4494 3848.7847 3839.8595 3830.6804 3821.2350 3811.5384 3791.3694

-3972.3159 -3968.6422 -.0012 -.OOO, .0042 -.0005 -.0001 .002, .0008 -3929,736, .OOlO -3917.3748 -.0042 .OO1, -.0008 -.OOO8 .0034 -.M)IZ -.0003 -.0005 -.0011 -.0026 .OOlO -.0026 .ooo* -3801.5794 .0056 -3780.8908 -3770.1613 -3759.1755 -3747.9340 -3736.4372 -3724.6856 -3712.6796

R

ee(2-l)

4134.1999 4136.5730 4138.6771 4140.5114 4142.0783 4143.3729 41‘4.4008 4145.1564 4145.6461 4145.8619 4145.4866 4144.8949 4144.0317 4142.9000 4141.4985 4139.8267 4137.8876 4135.6775 4133.1978 4130.4492 4127.4289 4124.1407 4120.5843 4116.7601 4112.6631 4108.2984

Qfe 3978.6012 3978.0710 3977.2726 3976.2156 3974.891‘ 3973.2953 3971.4469 3969.3214 3966.9384 3964.285, 3961.3753 3958.190, 3951.0373 3947.0632 3942.8268 3938.3247 3933.5625 3928.5360 3923.2445 3911.8742 3905.7956 3892.8490

-.0016 -.w)14 -.OOIO -.0012 .0007 -.ocQ4 .0014 .0004 .0032 .oo,, -4145.807, .0011 .co13 -.oooz -.0005 -.ooo* -.0017 -.0003 -.0002 -.0001 .OOOS -.0011 -,0012 -.0003 .OOlV .0004 .0001 -4103.6651 -4098.7633 -4093.5929 -4088.1543 -4082.4475 -4076.472, -4070.2302 -4063.7201

; 3 4 5 6 7

8

9 10 II 12 13 14 15 16 17 18

19 20 21 22 23 24 25 26 2, 28 29 30 31 32 33 34 35

J -

(3-Z)

-.oo,* -.0015 -.0042 -.0003 .0015 -.0035

-3954.7453 .0006 -.0003 -.0006 -.0023 -.0005 .0004 -.0005 -3917.6914 -.coov -.ooo, -3899.4552 -.0031 -3885.9873 -3818.8610 -3871.4736 -3863.8254 -3855.9166

13 14 15 16 1, 18 19 20 21 22 23 24 25 26 2, 28 29 30

-3847.7‘75 -3839.318, -3830.6302 -3821.6826 -3812.4762

31 32 33 34 35

ANALYSIS

OF THE w’A,-n’I&

SYSTEM

OF N,

241

TABLE I-Continued

J I 2 3 4 i 7

a 9 10 II I2 13 14 15 16 17 18 19 20 2, 22 23 24 25 26 27 28 29 30 31 32 33 34 35

R_ 3986.7048 3988.7877 3990.6057 3992.1548 3993.4366 3994.4609 3995.2109 3995.7003 3995.9172 3995.8725 3995.5614 3994.9776 3994.1374 3993.0272 3991.6511 3990.0393 3988.1007 3985.9283 3983.4822 3980.7aw 3977.8087 3974.5717 3971.0729 3967.3001 3963.2757 3958.9758 3954.4078 3944.4825

(3-Z)

Pff

-3984.3595 -.OOZ -.cn12

.ocm -.0006 -.0032 .0025 .0029 -.coo4

.0005

.0013 -.0044 -.oi305 -.0005 -.oao3 .OOOl -.OWI .0017 -.0043 -.0007 -.0005 - .0005 .0031 .cQ66

Q,,

-3972.3128 -3968.6397 3964.7026 3960.5000 3956.0374 3951.3010 3946.3057 3941.0489 3935.5239 3929.7461 3917.3844 3910.8125 3903.9783 3896.8824 3889.5236 3881.9017 3874.0295 3865.8823 3857.4826 3839.8997 3830.7163

.0047 -.0004 -3949.5806 -.0061 -3939.1322 -3933.5117 -3927.6273 -3921.4792 -3915.0677

(3-Z)

381

I .5832

3791.4187 3780.9493

.0006 .c003

. M42 -.0016 -.oo24 -.0012 -.0046

.cQ22

-3923.6962 -.0015 -.0007 . 0000 .0007 .0001 -.0022 .0058 -.wo3 .OO!l -3848.8204 -.0002 -.0039 -3821.2818 -.0019 -3801.6304

.ooo3

.OWI -3770.2234 -3759.2415 -3748.0039 -3736.5112 -3724.7638 -3712.7622

3978.6012 3978.0706 3977.2726 3976.2156 3974.8914 3973.2953 397 I. 4469 3969.3214 3966.9384 3961.3753 3954.7557 3947.0793 3942.8472 3938.3477 3933.5860 3928.5612 3923.2792 3917.7206 3911.9097 3905.8337 3899.4957 3892. a993 3886.0348 3878.9119 3871.5265 3863.8874 3855.9760 3847.8139

(3-Z)

Rff

.0015 .0011 -.0016 .0015 .I3025 -.c@34 .w31 -.oo25 -.w1o -3964.2903 -.0014 -3958.1987 -.0007 -3951 .oml -.wo3 .ooia . 0002

.woo

-.0002 .0055 -.0024 -.oooo -. 0003 -.ow4

.0029

-.COOl - .0002 -.0o1a .W36 -.W26 .nno3 -3689.3886 -3830.7042 -3821.7609 -3812.5588

3984.3574 3986.7048 3988.7877 3990.6057 3992. ,548 3993.4366 3994.4609 3995.2109 3995.7003 3995.9172

3994.9953 3994.1512 3993.0432 3991.6732 3990.0305 3988.1244 3985.9518 3983.5147 39ao.mzo 3977.8446 3974.6099 3971.,100 3967.3453 i963.3151 3959.0222 3949.6404 3939.1987

(3-Z) .0011 .0007 .0013 .w25 .0004 -.oo32 .0014 -.0023 -.coas -.0059 -3995.8791 -3995.5691 .0021 -.oooo -. 0000 .0038 wo9 .0004 -.OM)6 -.M)O5 -.0003 ,000, -.oooo -.0007 -.0009 -.w15 .oooO -3954.4628 .0014 -3944.5506 .0005 -3933.5816 -3927.7013 -3921.5575 -3915.1503

J

2 3

6

a 9

IO I I 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

DATA REDUCTION

The wavenumbers of the rotational lines have been simultaneously fitted by a computer program previously used in the treatment of the AlI&- W’A, transition of Pz (3). The wavenumbers are collected in Table I, together with the differences between observed and calculated values. Table II presents rotational constants for the u = 0, 1,2,3 levels of the w’A, state and for u = 0, 1, 2 of a’&. The band origins are ~~(0-0) = (2747.322 + 0.002) cm-l, ~~(1-0) = (4282.917 + 0.002) cm-l, ~~(2-1) = (4128.647 + 0.002) cm-‘, ~~(3-2) = (3978.866 t 0.002) cm-l. The A doubling in the 21= 0 level of the a ‘II, state was evaluated from measurements in the O-O and 1-O bands. The doubling increases normally up to J = 31 and shows an anomalous behavior after this value in the 1-O band. This is consistent with observations of Wilkinson and Houk (4). Unfortunately, high rotational levels were not observed in our experiment and it was not possible to study this perturbation.

242

ROUX ET AL. TABLE II Rotational Constants of the w’A, and alI& States of N, (cm-‘)

” = oa B

I .488105

Dx

lo6

“3

(18)

5.51

I

1.471763

a (18)

5.52

(2)

(2)

a’Il

” = oa

v=

g I

b

v=2

v=3

1.45544

(2)

1.43919

(3)

5.51

(1)

5.52

(2)

state

b

v = 2c

Be

1.60782

(2)

I .58984

(3)

1.57182

(3)

Bf

I.

(2)

I .58976

(3)

I .57173

(3)

5.90

(1)

5.92

(2)

5.97

(3)

5.90

(1)

5.92

(2)

5.96

(3)

IIF x

106

Df x lo6

60774

The numbers to

two

standard

a O-O and

b ’

in

parentheses

are

the

uncertainties

in

the

last

digits

that

correspond

deviations.

l-0

bands

fitted

2-1

band

@MS = 1.8

x

3-2

band

(RMS = 2 x

1O-3

simultaneously

lO-3

(REIS = 1.5

x

IO

-3

-1) cm

-I cm )

cm-‘)

Our results are in good agreement with the measurements RECEIVED:

C

of MC Farlane (1,2).

March 2, 1981 REFERENCES

I. R. A. MC FARLANE, IEEE J. Quantum Electron. 2, 229-232 (1966). 2. R. A. MC FARLANE, Phys. Rev. 146, 37-39 (1966). 3. C. AMIOT, C. EFFANTIN, J. D’INCAN, AND J. VERGES, J. Mol. Spectrosc. 72, 189-199 (1978). 4. P. G. WILKINSON AND W. B. HOUK, J. Chem. Phys. 24, 528-534 (1956).