THE ELECTRONIC SPECTRA OF PF AND PF+

1962 ◽  
Vol 40 (7) ◽  
pp. 832-849 ◽  
Author(s):  
A. E. Douglas ◽  
M. Frackowiak

Five band systems of PF and one of PF+ have been excited in a discharge through PF3 and have been photographed with a high resolution spectrograph. The rotational fine structures of a number of bands of each system have been analyzed and the rotational and vibrational constants determined. The principal constants for a 3Σ state of PF, which is believed to be the ground state, are ωe = 846.75 cm−1, Be = 0.5665 cm−1, re = 1.590 0 Å.


1959 ◽  
Vol 37 (5) ◽  
pp. 636-659 ◽  
Author(s):  
G. Herzberg ◽  
L. L. Howe

The Lyman bands of H2 have been investigated under high resolution with a view to improving the rotational and vibrational constants of H2 in its ground state. Precise Bv and ΔG values have been obtained for all vibrational levels of the ground state. One or two of the highest rotational levels of the last vibrational level (v = 14) lie above the dissociation limit. Both the [Formula: see text] and ΔG″ curves have a point of inflection at about v″ = 3. This makes it difficult to represent the whole course of each of these curves by a single formula and therefore makes the resulting equilibrium constants somewhat uncertain. This uncertainty is not very great for the rotational constants for which we find[Formula: see text]but is considerable for the vibrational constants ωe and ωexe for which three-, four-, five-, and six-term formulae give results diverging by ± 1 cm−1. The rotational and vibrational constants for the upper state [Formula: see text] of the Lyman bands are also determined. An appreciable correction to the position of the upper state is found.



1954 ◽  
Vol 32 (10) ◽  
pp. 630-634 ◽  
Author(s):  
B. P. Stoicheff

The pure rotational spectrum and the Q branch of the 1–0 band of N2 were photographed in the second order of a 21 ft. grating. An analysis of the rotational spectrum yields the rotational constants[Formula: see text]The value of B0 together with the Bν values obtained from the electronic bands of N2 gives[Formula: see text]Revised values of the vibrational constants have also been calculated using the results of the present work and the published data on the electronic spectra.



1971 ◽  
Vol 49 (10) ◽  
pp. 1249-1254 ◽  
Author(s):  
Midori Shimauchi

The emission spectrum of the AsS radical, excited in a quartz tube by a 2450 MHz oscillator, was photographed on a high resolution spectrograph from 2450 to 6900 Å. Seven bands around 6000 Å showing clear rotational structures were chosen for the first rotational analysis of the AsS spectrum. The bands were found to arise from a 2Π3/2–2Π3/2 transition. The rotational and vibrational constants of the two states derived from the present work are consistent with the previous vibrational analysis of the A′2Π3/2–X2Π3/2 system. The constants of the upper doublet component of the ground state, X2Π3/2, are ωe = 562.40 cm−1, ωexe = 2.02 cm−1, re = 2.0216 Å; the constants of the A′2Π3/2 state are ΔG′(1/2) = 403.37 cm−1, ν0,0 = 18 621.21 cm−1, re = 2.2500 Å.



1970 ◽  
Vol 48 (7) ◽  
pp. 901-914 ◽  
Author(s):  
W. J. Balfour ◽  
A. E. Douglas

The absorption spectrum of the Mg2 molecule, which occurs in a furnace containing Mg vapor, has been photographed with a high resolution spectrograph. The rotational structures of the bands have been analyzed and the rotational and vibrational constants of the two states determined. The bands are found to arise from a 1Σ–1Σ transition between a very lightly bonded ground state and a more stable excited state. The R.K.R. potential energy curve of the ground state, which has a dissociation energy of 399 cm−1, has been determined. The more important constants of the ground state are ωe = 51.12 cm−1, ωexe = 1.64 cm−1, re = 3.890 Å and those of the upper state are ωe = 190.61 cm−1, ωexe = 1.14 cm−1, re = 3.082 Å.



1957 ◽  
Vol 35 (10) ◽  
pp. 1242-1249 ◽  
Author(s):  
N. A. Narasimham

Two band systems attributed to the P2+ molecule have been excited in a hollow cathode discharge tube. The first of these is a 2Π—2Π band system lying in the region 3400–3850 Å. The lower state of this system probably is the ground state of the P2+ molecule. The second system is a 2Σ—2Σ system lying in the region 3900–4400 Å. High resolution spectra of both the band systems have been analyzed and the rotational and vibrational constants determined.



1994 ◽  
Vol 72 (11-12) ◽  
pp. 1225-1235 ◽  
Author(s):  
Walter J. Balfour ◽  
Ram S. Ram

The 266.7 nm absorption systems of toluene and seven deuterated isomers were observed at high resolution and analyses of their vibronic structure performed. All in-plane vibrations with ground-state frequencies less than 1000 cm−1 were identified from 0–1 hot bands. The frequencies agree well with data obtained from infrared and Raman studies. The corresponding vibrations were identified in the excited state. Information was also obtained on out-of-plane vibrations with ground-state frequencies less than 650 cm−1, since all of these are found to give sequence structure. A comparison of the measured data for the various isotopic species has enabled a consistent description of the excited state in toluene to be made. Problems associated with errors, ambiguities, and inconsistencies in previously published work have been addressed.



1985 ◽  
Vol 50 (11) ◽  
pp. 2480-2492 ◽  
Author(s):  
Soňa Přádná ◽  
Dušan Papoušek ◽  
Jyrki Kauppinen ◽  
Sergei P. Belov ◽  
Andrei F. Krupnov ◽  
...  

Fourier transform spectra of the ν2 band of PH3 have been remeasured with 0.0045 cm-1 resolution. Ground state combination differences from these data have been fitted simultaneously with the microwave and submillimeterwave data to determine the ground state spectroscopical parameters of PH3 including the parameters of the Δk = ± 3n interactions. The correlation between the latter parameters has been discussed from the point of view of the existence of two equivalent effective rotational operators which are related by a unitary transformation. The ΔJ = 0, +1, ΔK = 0 (A1 ↔ A2, E ↔ E) rotational transitions in the ν2 and ν4 states have been measured for the first time by using a microwave spectrometer and a radiofrequency spectrometer with acoustic detection.



1959 ◽  
Vol 37 (2) ◽  
pp. 136-143 ◽  
Author(s):  
Nand Lal Singh

The fine structures of three of the β bands of PO which occur near 3200 Å have been analyzed. The analysis shows that the upper state of this band system is a 2Σ and not a 2Π state as previously believed. The rotational constants of both electronic states have been determined and it is found that the ground state constants, previously determined from the γ bands, are incorrect.



1976 ◽  
Vol 54 (24) ◽  
pp. 2429-2434 ◽  
Author(s):  
B. R. Yadav ◽  
S. B. Rai ◽  
D. K. Rai

The visible emission spectrum of the GdO molecule has been produced in a DC arc source and has been photographed in the first order of a 10.6 m grating spectrograph. Bands are shown to have a six-headed structure and improved vibrational constants have been obtained in this study. Isotopic shifts have been calculated for the various isotopic molecules. Tentative suggestions regarding the nature of the transition have been made.



2011 ◽  
Vol 134 (23) ◽  
pp. 234306 ◽  
Author(s):  
Michael K. Bane ◽  
Evan G. Robertson ◽  
Christopher D. Thompson ◽  
Chris Medcraft ◽  
Dominique R. T. Appadoo ◽  
...  


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