Mohanty, B S

Pandey, R K

Upadhya, K N

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ROTATIONAL ANALYSIS OF THE A*X SYSTEM OFCul MOLECULER. K . PAN D EY, K . N . XJPADHYA a» i> B . S. M O H AN TYD epartm ent  of  Spectooscopy , B an a b a s  H in d u  U n iv k b s it y ,V a n a b a si^S, I n d ia .{Received December 18,1967 ; Resubmitted February 2, 1968)(Plate 6)ABSTRACT. The omission bands of the A-X system of the Cul moleoule lying in the rogioii 5600-47.50 A have boon photographed under higher dispersion and resolution. Rota- tioualanaly8i8of(l,0),(0,0)and(0,1) bands has been made. The transition involved is found to bo ifl — *S. The rotational constant of the two states are as follows (em“*) units):A  III state : Bo =  0.0674,« =  0.0001, g =  1.25 x 10~<X  ‘S state : Bo =  0.0732, a =  0.000217I N T R O D U C T I O NThe visible bands of the Oul molecule were studied by Mulliken (1926) and by Ritschl (1927). Ritschl recorded the bands in absorption and classihed them  in four systems with a common ground state for all o f them. O f these known systems, tho rotational analysis of the E -X , C -X  and D -X  systems were made by Nair and Uj^dhya (1966). Later Rao and Rao (1966) aiso reported tho rotational analysis of E, G and D  systems. Since a discrepancy existed regarding the cons­tants of the ground and excited states of those systems as reported by the two different workers, Nair and Rai (1967) from considerations of the expected periodic variation of tho r*-values in similar molecules indicated that the constants given by Rao and Rao (1966) were uncertain. In continuation of the work of Nair and Upadhya (1966) the present paper deals with the rotational analysis of the A -X  system of the Cul molecule.e x p e r i m e n t a lThe moleoule has been excited in an electrodeless discharge tube b j a 2450 mo/seo. Raytheon Microwave Oscillator. The rotational structures were photographed on a 10.6 metre grating spectrograph in the second order with a dispersion of 0.33 A/mm. The overlapping structure of the less abundant species C u «P « has been eliminated by adjusting the time of exposure. Since emission bands of this system are weak, it requiied 10 hours of exposure on Kodak IIF154PANDEY, UPADHYA AND MOHANTY Indian Journal of Physics Vol. 42 No. 3 PLATE 6Fig. I. Rotational structure of the 1,0 band of A-X system df Cul molecule.A~X System of Oul Molecule 165Plates. Iron arc spectrum was used for oomparison. The probable error in the measurement is estimated to be ±  0.04 cm~ .^A N A L Y S I S  A N D  D I S C U S S I O NThe throe bands (1,0), (0,0) and (0,1) were found suitable for measurement. The bands of the A system show two heauls (fig. 1, plate 6), one being the R head and the other Q head. The R head is quite week. Hotice, in the resolved structure only two series of lines, Q and P  could bo picked. The fine structure analysis indicates that the transition is ^n—^2. The Q Ijkanch is quite intense and runs to large J  values. The P  series is detected only at Itrge J values and runs towards the lesser frequency side. Yaccum wave numbers and J assignments o f the lines o f the analysed bands are given in table 1. :The J  numbering was fixed by comparing ^iF{J) values for common vibra­tional levels and employing the usual procedure (Herzberg; 1967). The rotational constant were obtained by the graphical method from the relation :AiP(J)j + i 2 R ,-4 D ,(J + 1 )*where A iP '(J) =  Q{J)-P{J+1)  and AiP'(J) =  Q(J+1)-P{J+1).  The band origins were determined from the intercepts of the graphs by plotting Q(J) against J(J+1). The a value for the upper state was determined graphically using the relation,In table 1 the ^jF"{J) values of the previous analysis for the E(Z, 0) band and AjJ’V l + A i f ’V - l )  =  Q{.J)-P[J+l)+Q{J-l) -P{J)= Aji'’''( J)-1-A v«(( tf — 1)-|-A Vei( )values for A(0, 0) and A (1, 0) bands are given. Since the two sets of values are very olose,it is confirmed that the transition is to the ground state. The regularly increasing difference in the two values is due to combinatior defect on account o f A-type doubling in the upper 1^1 state. The mean value of the A-splitting coeflS- cient, q was found to be 1.25x10“* om~*, from this table from the relation :l )+ ^ v ^ J )  =  2qJ*The band origins and the rotational constants are summarised in table 3.A C K N O W L E D G M E N T SThe authors wirii to express their sincere thanks to Prof. N. L. Singh for his valuable guidance. R.K.F. and B.S.M. are thankful to the Govt, o f India (Research Training Scheme) and National Bureau of Standards, U.S.A. respectively for finamoial assistance.Table 1Vacuum wave numbers and J assignments of the A bands of Cul15 6  B. K . Pandeyy K . N . Upadhya and B. 8. MohantyJ0.0 1.0 0,1Q(J) p{j ) Q(J) p(j ) Q{J) p(.j)25 19703.33 19914.15 19438.662fi 03.11 13.88 38.3827 02.93 13.61 38.1028 02.67 13.39 37.6529 02.32 13.04 37.2330 01.94 12.71 36.7231 01.58 12.42 36.2732 01.25 12.05 35.8533 19700.89 11.81 35.4234 00.49 11.43 34.9535 00.10 11.00 34.5136 19699.70 10.63 34.0837 99.29 10.28 33.6238 98.92 09.86 33.1539 98.51 09.45 32.6540 98.00 08.95 32.1341 97.65 19692.17 08.57 19902.95 31.0242 97.06 91.62 08.15 02.35 31.1043 96.58 91.04 07.62 01.98 30.5444 96.06 90.32 07.10 01.37 30.0245 95.53 89.62 06.63 19900.78 29.4546 95.09 89.03 06.13 00.14 28.96 19422.8247 94.63 88..34 05.57 J9899.52 28.34 22.1548 93.88 87.64 05.06 98.86 27.81 21.5749 93.34 86.94 04.50 98.18 27.10 20.7850 92.75 86.31 04.13 97.46 26.35 19.8151 92.17 85.62 03.47 90.75 25.79 19.0052 91.62 84.96 02.95 96.01 25.14 18.3553 91.04 84.24 02.35 95.32 24.49 17.6354 90.32 83.53 01.73 94.60 23.63 16.8155 89.91 82.74 01.13 93.89 22.96 16.0656 89.33 81.88 19900.50 93.11 22.28 15.2357 88.62 81.12 19899.90 92.66 21.67 14.4358 87.98 80.31 99.21 91.98 20.90 13.6659 87.28 79.77 98.57 90.99 20.19 12.7860 86.61 78.87 97.88 90.00 . 19.43 11.97A-X System of Cul MdecvleTable 1 {ConM.)157J0,0 1.0 0.1Q{J) F {J ) Q(J) p(j) Q(J) P(J)61 85.95 78.12 97.17 89.27 18.70 11.11f}2 85.30 77.13 96.49 88.46 17.98 10.2563 84.49 76.34 95.78 87.69 17.20 09.4764 83.81 75.49 95.07 86.78 16.45 08.3465 83.08 74.82 94.32 85.92 16.67 07.6066 82.30 74.00 93.60 85.05 14.92 06.6767 81.59 73.09 82.83 84.30 14.09 05.9068 80.80 72.15 92.12 83.49 13.28 05.0869 80.05 71.39 91.41 82.55 12.50 04.1170 79.23 70.44 90.64 81.65 11.65 03.1671 78.47 69.48 89.68 80.73 10.84 02.2172 77.58 68.65 88.92 79.76 09.96 01.2873 76.80 67.78 88.00 78.99 09 10 00.2474 76.09 66.80 87.21 78.03 08.14 19399.3275 75.27 65.99 86.36 77.05 07.34 98.2976 74.34 65.05 85.50 75.80 06.57 97.2677 73.44 64.08 84.58 74.84 05.59 96.1378 72.63 63.10 83.70 73.89 04.95 95.2879 71.81 62.09 82.79 72.9880 70.90 60.84 81.84 71.7881 70.09 59.84 80.92 70.7782 69.26 58.81 79.96 69.6583 68.30 57.88 78.99 68.5884 67.35 56.83 78.03 67.5285 66.36 55.62 77.05 66.3086 65.32 54.50 75.88 65.1687 64.24 53.40 74.92 64.0188 63.36 52.33 73.98 62,8789 62.46 51.24 73.08 61.7290 61.10 50.05 72.07 60.5391 70.9692 69.9293 68.8494 67.7395 66.6596 65.4997 64.3898 63.2699 62.09100 60.98Table 2A-type splitting in the =  0 level of the A 1^1 state of Cul158 R. K. Pandey, &. N. Upadhya and B. 8. MohantyJA2^ "( J) Ai J) + - 1) = ^ 2F''{J) H- a — 1)+ AV<;d(J)0) bund moan of A (0,0) and A(1,0) bandsAVc<f(J —1' Avcrf(c/)=:41 12.12 11.76 0.3642 12.38 11.95 0.4343 12.72 12.28 0.4444 12.97 12.64 0.3345 13.28 12.88 0.4040 13.59 13.18 0.4147 13.84 13.53 0.3148 14.13 13.77 0.3649 14.49 13.96 0.6350 14.74 14.31 0.4351 15.04 14.61 0.4352 15.35 14.85 0.6053 15.62 15.18 0.4454 15.88 15.39 0.4955 16.17 15.70 0.4756 16.50 16.06 0.4657 16.80 16.19 0.6158 17.07 16.33 0.7459 17.42 16.67 0.7560 17.65 17.00 0.6501 18.01 17.21 0.8062 18 26 17.46 0.8063 18.49 17.80 0.6964 18.85 18.06 0.7965 19.16 18.23 0.8366 19.36 18.43 0.9867 19.70 18.65 1.0568 19.99 18 88 1.1169 20.30 19.17 1.1370 — 19.61 __71 20.89 19.70 1.1972 21.20 19.74 1.4673 21.47 19 89 1.5874 21.73 20.24 1.4975 22.01 20.62 1.4976 22.29 20.85 1.4477 22.66 20.98 1.6778 22.88 21.15 1.7379 23.20 21.62 1.6880 23.61 22.02 1.6981 23.88 22.19 1.6982 24.08 22.35 1.7383 24.39 22.66 1.7484 24.64 22.85 1.7986 24.96 23.20 1.7686 26.21 23.60 1.6187 26.50 23.76 1.7488 25.87 23.87 2.0089 26.26 24.36 1.90A -X  System of Oul Moleeide 159Table 3Rotational constants and Band origins for the A —X  system of Oul (cm~ )^Band Bv' Bv^0,0 0.0674 0.0730 19707.400,1 0.0674 0.0732 19442.931,0 0.0073 0.0730 10917.40B,' =  0.06743, B / 0.0733a.’ =  0.0001, a." = 0.0002r." -- 2.38 A, g = 1.25x10“^< =  2.48 AR E F E B E N C E SHorzberg, G., 1957, Spectra of Diatomic Molecules D . Van Nostrand Co. Inc. NY. 189-190. Mulliken, R. S., 1925, Phys» Rev, 26, 1.Nair, K. P. R. and Upadhya, K. N., 1966, Can. J. P hys. 44, 1267.Nair, K. P. R. and Rai, D. K., 1907, Can. J. PhtjA. 45, 2810.Rao, P. R. K. and Rao, K, V. S. R., 1966, C7an. J. P h ys. 44, 2241, 2247.Ritschl, R., 1927, Z . Physik, 42, 172.

Rotational Analysis of the A-X System of Cul Molecule

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Rotational Analysis of the A-X System of Cul Molecule

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