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Herzberg bands

Fig. V-14. Potential energy curves of Oj. S-R, Schumann-Runge bands H, Herzberg bands A-A, atmospheric bands. The line-broadening was observed at r = 4 of the fl3 state at which point the repulsive 3n. state crosses the B5I state. See Murrell and Taylor (726). From Dissociation Energies and the Spectra of Diatomic Molecules" by Caydon, 3rd Ed. 1968, p. 74, reprinted by permission of Associated Book Publishers Ltd. Fig. V-14. Potential energy curves of Oj. S-R, Schumann-Runge bands H, Herzberg bands A-A, atmospheric bands. The line-broadening was observed at r = 4 of the fl3 state at which point the repulsive 3n. state crosses the B5I state. See Murrell and Taylor (726). From Dissociation Energies and the Spectra of Diatomic Molecules" by Caydon, 3rd Ed. 1968, p. 74, reprinted by permission of Associated Book Publishers Ltd.
The upper limit corresponds to the convergence limit for the Herzberg bands (42). [Pg.48]

Fig. 8. Absorption coefficients of 02, 03, and 002. The forbidden Herzberg bands above 2000 A. are replaced by a smooth curve to show the approximate absorption coefficients in this region. Superposed banded structure of COj are smoothed and absorption coefficients are approximate. [Source of data () , 25C0-1900 A. ref. 23 R. W. Ditchburn and D. W. 0. Heddle, Proc. Roy. Soc. (London), A220, 65 (1953) Oj, 1200-1900 A., K. Watanabe, E. C. Y. Inn. and M. Zelikoff, J. Chem. Phya., 21, 1026 (1953) 03, ref. 28 H. K. Pitzold and E. Regener, Handbuch der Physik, Vol. Springer-Verlag, Berlin, 1957, p. 370 C02, ref. 45. ... Fig. 8. Absorption coefficients of 02, 03, and 002. The forbidden Herzberg bands above 2000 A. are replaced by a smooth curve to show the approximate absorption coefficients in this region. Superposed banded structure of COj are smoothed and absorption coefficients are approximate. [Source of data () , 25C0-1900 A. ref. 23 R. W. Ditchburn and D. W. 0. Heddle, Proc. Roy. Soc. (London), A220, 65 (1953) Oj, 1200-1900 A., K. Watanabe, E. C. Y. Inn. and M. Zelikoff, J. Chem. Phya., 21, 1026 (1953) 03, ref. 28 H. K. Pitzold and E. Regener, Handbuch der Physik, Vol. Springer-Verlag, Berlin, 1957, p. 370 C02, ref. 45. ...
Absorption within the forbidden Herzberg band, originating near 2454 A, gives the forbidden transition... [Pg.514]

The answer, very often, is that they do not obtain any intensity. Many such vibronic transitions, involving non-totally symmetric vibrations but which are allowed by symmetry, can be devised in many electronic band systems but, in practice, few have sufficient intensity to be observed. For those that do have sufficient intensity the explanation first put forward as to how it is derived was due to Herzberg and Teller. [Pg.281]

The C state has attracted much attention from spectroscopists because the state was believed to be the upper state of the ultraviolet absorption band which can help establish the accurate dissociation energy of the ground state of H2 [82]. Therefore, several attempts have been made to obtain the complete PEC for the C state [53,76,83,84]. The calculations by Browne revealed that there exists a suspicious maximum at i = 8a.u. which is about 160 cm above the dissociation limit [76]. This observation was consistent with the conclusion of Herzberg and Monfils that a maximum might exist in the vicinity of / — 13 a.u. [82]. The subsequent calculations by Kolos and Wolniewicz [53], and Namioka [77] refined the barrier to be about 105.5 cm at i = 9 a.u. The computed PEC for the C state and the fitted spectroscopic parameters (r, v, v Xe, a ) in the present study agree well with the experiment, as demonstrated by Table 8. [Pg.75]

The rotational selection rule is A / = 0, +1, except for the case of a transition involving ft = 0 for both the upper and lower states. Thus three sets of lines (known as the P, Q, and R branches) corresponding to A J= —1, 0, and +1, respectively, are observed for each band arising from a particular vibrational transition. Figure 3.5 illustrates these transitions schematically. However, if ft = 0 for both upper and lower states ( 2 -> 2 transition), the rotational selection rule is A J = +1, and the Q branch does not appear. For further details, see Herzberg (1945, 1950, 1967). [Pg.48]

FIGURE 4-1 Potential energy curves for ground and first four excited states of 02. S-R = Schumann-Runge system, H = Herzberg continuum, A-A = atmospheric bands (adapted from Gay-don, 1968). [Pg.87]

Yoshino, K., J. R. Esmond, A. S.-C. Cheung, D. E. Freeman, and W. H. Parkinson, High Resolution Absorption Cross Sections in the Transmission Window Region of the Schumann-Runge Bands and Herzberg Continuum of 02, Planet. Space Sci.., 40, 185-192... [Pg.129]

It is, therefore, noteworthy that almost immediately upon Welsh and associates discovery of collision-induced absorption in hydrogen [128, 129, 420], Herzberg found the first direct evidence of the H2 molecule in the atmospheres of the outer planets [181, 182], He was able to reproduce in the laboratory the unidentified diffuse feature at 827.0 nm observed by Kuiper in the spectra of Uranus and Neptune, using an 80 m path of hydrogen at 100 atmospheres pressure and a temperature of 78 K. The feature is the S3(0) line of the 3 — 0 collision-induced rotovibrational band of the H2 molecule [182]. [Pg.371]

Herzberg was able to point out another line at 816.6 nm which he identified as a double transition, partially overlapped by an adjacent CH4 band in the Uranus spectra. In the laboratory spectra recorded with unmixed hydrogen, this double transition was relatively strong, but in the photographic plates of Uranus the feature was much weaker relative to the S3(0) line. This observation led Herzberg to conclude that sizeable He concentrations exist in these atmospheres (albeit the estimates of [He] [H2] abundance ratio seem high), because the S3(0) feature is enhanced by the presence of He, but H2-He pairs cannot undergo double transitions these features thus appear weak in Kuiper s plates relative to the S3(0) feature. [Pg.371]

The ground state is X L+ D0(H—CN) = 5.20 0.05 eV (264). Hydrogen cyanide has no absorption in the visible and near ultraviolet regions. It starts to absorb weakly at about 1900 A. Herzberg and Innes (463) have found three band systems in the region 1350 to 1900 A, corresponding to the y, (I, and a systems. The upper states are all bent. [Pg.42]

Fig. V-8. Energy level diagram of CO A-X, fourth positive B-A, Angstrom C-A, Herzberg B-X, Hoptield Birge a-X, Cameron d-a, triplet e-a. Merman b-a, third positive c-a, 3A bands a -a, Asundi. The 1470 A line is in coincidence with the Fig. V-8. Energy level diagram of CO A-X, fourth positive B-A, Angstrom C-A, Herzberg B-X, Hoptield Birge a-X, Cameron d-a, triplet e-a. Merman b-a, third positive c-a, 3A bands a -a, Asundi. The 1470 A line is in coincidence with the </3A (r = 7) (898). From Caydon (8), p. 210, reprinted by permission of Associated Book Publishers l.td.
Plwtodissociatiqn of 02 in the Upper Atmosphere. The source of O atoms above an altitude of 50 km is mainly from the photolysis of 02 in the Herzberg I and Schumann-Runge continua (488). The predissociation of 02 in the Schumann Runge bands (r > 3) [Wray and Fried (1054)] is the additional source of O atoms between 65 and 95 km. Supporting evidence of the predissoeiation is that no fluorescence of the Schumann-Runge bands above v > 1 has been observed in the upper atmosphere. [Pg.174]

From 200 to 242 nm, the 02 absorption, which is related to the Herzberg continuum with low absorption cross section, occurs in the stratosphere. In this spectral region, the ozone absorption must be introduced since the 03 Hartley band is characterized by high values of the absorption cross section between 200 and 300 nm. The simultaneous absorption by 02 and 03 must be considered in the stratosphere, whereas the O3 absorption is practically negligible in the mesosphere since the total number of absorbing ozone molecules is small. [Pg.64]


See other pages where Herzberg bands is mentioned: [Pg.47]    [Pg.146]    [Pg.167]    [Pg.45]    [Pg.139]    [Pg.65]    [Pg.51]    [Pg.116]    [Pg.77]    [Pg.77]    [Pg.47]    [Pg.146]    [Pg.167]    [Pg.45]    [Pg.139]    [Pg.65]    [Pg.51]    [Pg.116]    [Pg.77]    [Pg.77]    [Pg.515]    [Pg.416]    [Pg.623]    [Pg.101]    [Pg.254]    [Pg.300]    [Pg.86]    [Pg.10]    [Pg.225]    [Pg.1277]    [Pg.9]    [Pg.66]    [Pg.173]    [Pg.213]    [Pg.218]    [Pg.405]    [Pg.201]    [Pg.378]    [Pg.35]    [Pg.92]   
See also in sourсe #XX -- [ Pg.51 , Pg.116 ]




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