W.T.M.L. Fernando et al- Fourier Transform Emission Spectroscopy of the A^1-Sigma^+-X^1-Sigma^+...

8/2/2019 W.T.M.L. Fernando et al- Fourier Transform Emission Spectroscopy of the A^1-Sigma^+-X^1-Sigma^+ Transition o

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JOURNAL OF MOLECULAR SPECTROSCOPY 139,46 l-464 (1990)

Fourier Transform Emission Spectroscopy of the AZ+-X Z+ Transition of CUDThe A Z +-X Z + transition of CUD near 4300 A was previously recorded by Heimer ( I), Jeppesen (2).

and Ringstrom (3). Many of the excited vibrational levels of the A Z+ state are perturbed (3) and. for CuH,display some evidence of predissociation by a %+ state (4. 5).

The CuH molecule is of astrophysical interest. Hauge (6) observed the AZ-XZ+ transition in thespectrum of a sunspot. CuH was also tentatively identified in the spectrum of the star 19 Piscium (7).

In the course of our work on BD, we identified the O-O, O-I, and 1- 1 bands of the A Z:+-X Z + transitionof CUD. These Fourier transform data provide much improved spectroscopic constants for 63C~D and 65C~Dincluding rotational constants and a value for AG , 2 n the ground state. The new CUD ground state constantscomplement our recent observations of the vibration-rotation spectrum of CuH ( 8).

The CUD molecule was made in a hollow cathode discharge. In this experiment, a 1:3 mixture of B&Ipowder and copper powder was pressed and drilled to form a hollow cathode. The composite-wall hollowcathode was operated at 400 mA with a flow of 1.6 Torr of Ar gas and 35 mTorr of Dz gas.The emission from the hollow cathode was observed with the McMath Fourier transform spectrometerof the National Solar Observatory at Ritt Peak. 33 scans were coadded in 1.5 hr of integration with anunapodized resolution of 0.05 cm-.

A prism monochromator, acting as a filter, limited the wavelength response of the cooled GaAs photo-multiplier detectors to approximately 2 1 700-24 000 cm-. The spectra were calibrated to an absoluteaccuracy of about 0.002 cm- with the Ar+ atomic line positions of Norlen (9).

The line positions were determined from the spectrum by a data-reduction program, PC-DECOMP,developed at Kitt Peak. This program fits the spectral features with Voigt lineshape functions to determine

CUD AZ+-XZ1 2 1 1 1 0

0 1 2 3

23340 232

I (J 1

cm-lFIG. 1.The R-branch for the O-O band of the A 2+-X 2+ transition of CUD.

461 0022-2852190 $3.00Copyright 0 I990y Academic Press. Inc.All rights of reproduction in any form resewed.


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462 NOTESTABLE I

The Observed Line Positions for the A 2+-X Z+ Transition of CUD (in cm-)%UD %uD

J P(J) O-C' R(J) o-c P(J) o-c NJ) O-C

21971.998721963.359721953.862821943.534221932.370921920.362721907.545121893.9002

23142.615823133.774623123.911823113.018423101.099623088.171823074.226823059.275323043.313723026.363623008.418822989.487922969.579522948.692822926.850922904.045222880.288422855.585222829.949622803.380022775.883922747.4791

021986.7598-115 21992.8541-26 21998.0969-78 22002.4786-49 22006.0019

-1078 22008.661922010.4584-39 22011.3908-34 22011.455722010.670922009.012122006.488622003.100821998.861621993.752921987.793621980.975021973.300921964.774321955.409121945.1732

-5; 21972.6524: 21964.005421954.5137;: 21944.193121933.026617 21921.0473-4: 21908.239521894.60304840.:a32-10:9'-5-45

-1;:l- 1 Band

23157.1765-3'0" 23162.899023167.5823-;4" 23171.215923173.7967-69 23175.33971:: 23175.827623175.2693-465 23173.654423170.9842:: 23167.266323162.4941-8 23156.6719

-500 23149.800223141.87254 23132.89816 23122.873114 23111.80532 23099.68692'9' 23086.527323072.3260-20 23057.0894-9 23040.8105

1 Band

10429 23142.713123133.8873-3': 23124.034523113.1499-1 23101.248823088.32643': 23074.396423059.4532-8 23043.51112 23026.5831-7 23008.65363: 22989.737622969.84626 22948.9916

-11' 22927.159922904.3760-:: 22880.640122855.9623-26 22830.3452-30 22803.8056:6" 22776.337422747.9564

21987.3806-95 21993.4744-:;

21998.709922003.0837-71 22006.6129-175 22009.2583-102 22011.0521-63 22011.9864-108 22012.053322011.263722009.612077007 0922

21965.424821956.053921945.8463

23157.267123162.974823167.661340 23171.2746j 23173.8703-:1" 23175.89063175.4086-338 23173.72973175.3296

-46 23171.0558-47 23167.3473-:a 23162.580023156.7662-30 23149.905637 23141.9841-19 23133.0202-18 23123.0043-28 23111.9513-20 23099.8488-18 73086.7009ii 23072.5i611: 23057.288423041.0303

216':1::-1:-;",I:z:10-1'8-12-6471-24

."3"081981:-56-5465-4513;t::.:t2'0"-13-1';49

' Observed minus calculated line positions using the constants of Table II(in units of 10.' m-').

the peak positions. Because the spectrum was slightly under-resolved, most of the strong lines producedringing. A special option in PC-DECOMP called filtered fitting was used to improve the resolution byremoving the effect of the instrumental sine function lineshape.

Lines for 63C~D and for 65C~D were measured for O-O, I- 1, and 0- 1 bands of the A Z l -X 2 + ransitionand are listed in Table I. Part of the R head of the O-O band is shown in Fig. 1.The observed linewidth ofthe CUD lines was approximately .095 cm- and the transitions were easily assigned with the help of Jeppesenswork (2).

Copper has two stable isotopes, 63Cu and 65Cu (69.2 and 30.8%). At higher J values a doublet patterndue to the two isotopomers was observed in the O-O and 1 1 bands. In the 0- 1 band, the lines from the twoisotopomers were well separated.

All of the lines for the O-O, 1 1, and O-l vibrational bands were fitted together for each isotopomer usingthe customary energy level expressionF(J) = V, + BJ(J + 1) - D[J(J + 1)]2 + H[J(J + 1 )I.


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NOTES 463TABLE l-Continued

63C~D "CUDP(J) o-c R(J) O-C P(J) o-c R(J) o-c

23318.044623309.025223298.991223287.919523275.835623262.736223248.625923233.505623217.394223200.291623182.207123163.140823143.103823122.102823100.144523077.240623053.398123028.622923002.925022976.317522948.796422920.394122891.097122860.925622829.888022798.001722765.264622731.692022697.292222662.080822626.060322589.241622551.643422513.264522474.115522434.212822393.555322352.164122310.037522267.1826

.::654842-27-27-2314:i206:o":;-:3"40

7-17-46.i:-16-33-6-9-321422226-82419-35

0 - 0 Bs d23332.976423338.888723343.760123347.589823350.376023352.115523352.811823352.461423351.063123348.619323345.128923340.594123335.016223328.393023320.727823312.021523302.283923291.511423279.715523266.888323253.041223238.168023222.283223205.387923187.491123168.588823148.691123127.801623105.919523083.070123059.234323034.428623008.653622981.930422954.231622925.594022896.006522865.475222834.0077

-10.;':-22-24-42-30-19-19-7i18444225-20-20-396228-18-I1-44-11-18-13-9-6327::-398346-::-40

23318.053923309.047423299.009223287.955523275.884323262.801523248.705523233.606523217.513023200.425623182.351323163.300723143.279423122.305623100.375923077.489423053.663523028.912323003.242022976.657322949.164722920.783522891.520222861.374322830.364122798.506822765.805922732.264822697.895722662.713222626.730222589.951722552.378322514.031822474.923322435.047222394.438422353.085722310.997422268.1775

23332.9764-12 23338.8807-10 23343.7474-59 23347.5748-36 23350.3590-6 23352.096142 23352.792341 23352.440538 23351.044959 23348.601649 23345.1155.:2 23340.583823335.0093-46 23328.39148265 23320.740323312.046548 23302.31853 23291.5597295 23279.775023266.9615.:2' 23253.122323238.2778-5 23222.4092.'2i 23205.534123187.6476-70 23168.7628-35 23148.890215 23128.0226.:: 23106.168623083.3363-21 23059.524618 23034.743958 23009.0020-1; 22982.299422954.6396-'6: 22926.02441550-2:

20-ii-13-24.;9'-io'-8-10-11-329-5-13-11:z-29::.I;:-49-5-5-11-1';-262:-2':

TABLE IIMolecular Constants for the AZ+-XZ+ Transition of CUD (in cm-).

X1X+ A'C'constanr v - 0 v-1 v-0 v=l

T 0.0B 3.992396(20)D, 10' 1.36296(27)H, 10' 2.819(u)

T 0.0 1345.5958(15)B 3.988482(27) 3.896603(44)D, 10" 1.35903(43) 1.3429(16)H, lo9 2.785(19) 2 62(22)

1346.2171(12)3.900452(31)1 3485(12)2.69(16)

%uD

23326.02770(64) 24496.6296(14)3.475075(20) 3.381743(34)1.20200(28) l-2149(13)1.565(11) 8.5(16)

23326.03150(83) 24496.1001(19)3.471678(28) 3.378417147)1.19831(47) 1.2085(18)1.535(22) 5.8(23)

Note. One standard deviation uncertainty is enclosed in parentheses.


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464 NOTESThe molecular constants from our two fits are provided in Table II. These constants are in reasonableagreement with less accurate previous values.

ACKNOWLEDGMENTSThe National Solar Observatory is operated by the Association of Universities for Research in Astronomy,

Inc., under contract with the National Science Foundation. We thank J. Wagner, C. Plymate, and G. Laddfor assistance in recording the spectra. Acknowledgment is made to the Petroleum Research Fund, administeredby the American Chemical Society, for the support of this work.

REFERENCES1. T. HEIMER,Nat urwis senschaften 23,312 (1935).2. M. A. J EPPESE N, hy s. Rev . 50,445-449 (1936).3. U. RINGSTR~M,Ark . Fys . 32,21 l-239 (1966).4. G. HERZBERGAND L. G. MLJ NDIE, . Chem. Phy s. 8,263-273 ( 1940).5. B. KLEMAN,Ark . Fys . 6, 17-24 ( 1953).6. 0. HAUGE, Astron. Astrophys. 1 0 , 73-15 ( 1971).7. R. S. WOJ SLAWAND B. F. PE RRY, R,As trophy s. J. Supp l. 31,75-92 ( 1976).8. R. S. RAM, P. F. BERNATH,AND J . W. BRAULT, J. Mol. Spectrosc. 113 ,269 -274 ( 1985).9. G. NORLEN,Phy s. scripta 8,249-268 ( 1973).

W. T. M. L. FERNANDOL. C. OBRIENIP. F. BERNATH

Departm ent of Chemist ryThe University of ArizonaTucson, A rizona 85 721

Received Oct ober IO, 1989

Current address: Food and Drug Administration, Division of Drug Analysis, 1114 Market St., St. Louis,Missouri 63101.* Alfred P. Sloan fellow; Camille and Henry Dreyfus teacher-scholar.

W.T.M.L. Fernando et al- Fourier Transform Emission Spectroscopy of the A^1-Sigma^+-X^1-Sigma^+...

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