THE ABSORPTION SPECTRUM OF 35Cl2 FROM 4780 TO 6000 Å

1963 ◽  
Vol 41 (7) ◽  
pp. 1174-1192 ◽  
Author(s):  
A. E. Douglas ◽  
Chr. Kn. Møller ◽  
B. P. Stoicheff
Keyword(s):  
Absorption Spectrum ◽  
High Resolution ◽  
Ground State ◽  
Dissociation Limit ◽  
Complex Spectrum ◽  
Absorption Bands ◽  
Isotopic Species ◽  
Concave Grating

The discrete absorption bands of gaseous chlorine which lie between 6000 Å and the dissociation limit, near 4780 Å, have been photographed at high resolution with a 10-meter concave-grating spectrograph. This complex spectrum has been simplified by the use of the separated isotopic species 35Cl2 and by cooling the cell. An analysis of all the strong bands has been achieved. The principal constants of the ground state are Be = 0.24407, α = 0.00153, ωe = 559.71, ωexe = 2.70, [Formula: see text], and re = 1.9878 Å.

High resolution absorption spectrum of nitric oxide (NO) in the region of the first ionization limit

1976 ◽  
Vol 54 (20) ◽  
pp. 2074-2092 ◽  
Author(s):  
E. Miescher
Keyword(s):  
Absorption Spectrum ◽  
High Resolution ◽  
Ionization Energy ◽  
Dissociation Limit ◽  
Matrix Elements ◽  
Rydberg Series ◽  
Isotopic Species ◽  
Vibrational Levels ◽  
Energy Formula ◽  
Ionization Limit

The absorption spectrum of cold NO gas has been photographed at high resolution between 1400 and 1250 Å for two isotopic species. Resolved bands of the Rydberg series converging to vibrational levels of the 1Σ+ ground state of NO+ are studied. They include nf–X bands up to n = 15 and ns–X bands up to n = 11, all of which show sharp rotational structure. The higher members of the np–X series are generally very diffuse with only npσ being sufficiently sharp to show broadened rotational lines. Also mostly diffuse are the ndδ–X bands. The bands ndσ, π–X are not observed. The rapidly (n−3) narrowing structure of the nf complexes is discussed and the ionization energy [Formula: see text] accurately determined by extrapolation of selected rotational lines. Interactions between Rydberg states are numerous, s ~ d mixing produces a strong effect above n = 6 when (n + 1)s levels fuse with nl levels into 'supercomplexes'. Matrix elements are given for observed 8f ~ 9s and 6f ~ 6dδ interactions.Valence levels are not observed above the ionization energy, except for the repulsive state A′2Σ+ arising from the first dissociation limit and seemingly assuming Rydberg character at molecular internuclear distance. Observed anomalies are qualitatively discussed.

THE LYMAN BANDS OF MOLECULAR HYDROGEN

1959 ◽  
Vol 37 (5) ◽  
pp. 636-659 ◽  
Author(s):  
G. Herzberg ◽  
L. L. Howe
Keyword(s):  
High Resolution ◽  
Vibrational Level ◽  
Ground State ◽  
Molecular Hydrogen ◽  
Equilibrium Constants ◽  
Dissociation Limit ◽  
Vibrational Levels ◽  
State Formula ◽  
Single Formula ◽  
Vibrational Constants

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.

scholarly journals Absorption Spectrum of As2 Further Analysis of the A→X System and Observation of New Electronic States

1974 ◽  
Vol 29 (3) ◽  
pp. 429-435 ◽  
Author(s):  
Abdel Mooti Sibaï ◽  
Pierre Perdigon ◽  
Ari Topouzkhanian
Keyword(s):  
Absorption Spectrum ◽  
High Resolution ◽  
Energy Range ◽  
Electronic States ◽  
Absorption Bands ◽  
High Resolution Analysis ◽  
Resolution Analysis

Within the study of the interaction between A and B states of As2 molecule, a high resolution analysis of 16 absorption bands with 11 ≦ υ ≦ 17 in the A ← X system has been performed. The following constants are proposed for the A state: T00 = 40145.9 cm-1, ωe = 262.7 cm-1, ωe xe = 0.48 cm-1, Be = 0.0797 cm-1, De ≅ 3 X 10-8 cm-1 , αe = 0.00031 cm-1 , re = 2.374 Å. Three new vibronic levels have been discovered in the 42 400 -44 500 cm-1 energy range, either directly or by the perturbations they induce in A levels

The A2Πi–X2Πi absorption spectrum of BrO

1981 ◽  
Vol 59 (12) ◽  
pp. 1908-1916 ◽  
Author(s):  
M. Barnett ◽  
E. A. Cohen ◽  
D. A. Ramsay
Keyword(s):  
Absorption Spectrum ◽  
Absorption Spectra ◽  
Ground State ◽  
Flash Photolysis ◽  
Absorption Bands ◽  
Long Wavelength ◽  
Numbering Scheme ◽  
Ozonized Oxygen ◽  
Good Agreement

Absorption spectra of isotopically enriched 81Br16O and of normal BrO have been obtained by the flash photolysis of mixtures of bromine and ozonized oxygen. Rotational analyses are given for the 7–0, 12–0, 18–0, 19–0, 20–0, 21–0, 7–1, and 20–1 A2Π3/2–X2Π3/2 sub-bands of 81Br16O. The value for [Formula: see text] is found to be 722.1 ± 1.1 cm−1 in good agreement with the value calculated from microwave constants. Several additional bands have been found at the long wavelength end of the spectrum, necessitating a revision of the vibrational numbering scheme for both the emission and absorption bands. "Hot" bands up to ν″ = 6 have been observed in the absorption spectrum for the 2Π3/2 component of the ground state but no bands have yet been identified from the 2Π1/2 component.

ON THE ABSORPTION SPECTRUM OF H2O AND D2O IN THE VACUUM ULTRAVIOLET

1963 ◽  
Vol 41 (2) ◽  
pp. 209-219 ◽  
Author(s):  
J. W. C. Johns
Keyword(s):  
Absorption Spectrum ◽  
Water Vapor ◽  
High Resolution ◽  
Heavy Water ◽  
Vacuum Ultraviolet ◽  
Rydberg Series ◽  
Accuracy Of Measurement ◽  
Concave Grating

The spectra of normal and heavy water vapor have been observed under high resolution in the region 1220–1240 Å. One band of H2O and two bands of D2O have been measured and analyzed. The spectra were taken in the ninth order of a 35-ft concave-grating spectrograph and the accuracy of measurement of the sharper lines is estimated to be about ± 0.005 Å. The results of the analyses are summarized below.[Formula: see text]These bands have been assigned as belonging to the first member of one of the two np Rydberg series.

ABSORPTION SPECTRA OF C3 AND C3H2 FROM THE FLASH PHOTOLYSIS OF DIAZOPROPYNE

1967 ◽  
Vol 45 (12) ◽  
pp. 4103-4111 ◽  
Author(s):  
A. J. Merer
Keyword(s):  
Absorption Spectrum ◽  
Free Radical ◽  
Ground State ◽  
Time Delays ◽  
Flash Photolysis ◽  
State Level ◽  
Vibrational Structure ◽  
Absorption Bands ◽  
Text Component ◽  
Ground State Level

The flash photolysis of diazopropyne (HC2∙CHN2) provides a particularly strong absorption spectrum of the free C3 radical. About 40 μs after the photolysis flash, the appearance of the [Formula: see text] (4 050 Å) system of C3 is similar to that obtained in the flash photolysis of diazomethane by Gausset, Herzberg, Lagerqvist, and Rosen, though much more intense. The intensity of the spectrum has permitted a study of the l-type doubling effect in the ground-state level 6ν2, of which the [Formula: see text] component has been found to lie at 458.2 cm−1. At shorter time delays [Formula: see text] the spectrum is complicated by bands arising from the levels ν1″ (1 224.5 cm−1) and 2ν1″ (2 436.0 cm−1).Below 3 700 Å the C3 spectrum is overlapped by absorption bands belonging to a new free radical, which has been identified from the intensity alternation in the rotational structure as the HCCCH radical. The vibrational structure of this system is exceptionally complex, and analysis has not been possible. The bands extend to about 3 100 Å, but are predissociated below 3 450 Å.

THE 2 700 Å BANDS OF THE N3 MOLECULE

1965 ◽  
Vol 43 (12) ◽  
pp. 2216-2221 ◽  
Author(s):  
A. E. Douglas ◽  
W. Jeremy Jones
Keyword(s):  
Fine Structure ◽  
High Resolution ◽  
Ground State ◽  
Flash Photolysis ◽  
Bond Distance ◽  
Absorption Bands

The 2 700 Å absorption bands found by Thrush in the flash photolysis of HN3 have been studied at high resolution. The rotational fine structure of the strongest band has been analyzed, and it has been shown that the bands arise from a [Formula: see text] transition of the N3 molecule. The bond distance in the ground state of N3 is found to be 1.181 Å.

Absorption spectrum of the Mg2 molecule

1970 ◽  
Vol 48 (7) ◽  
pp. 901-914 ◽  
Author(s):  
W. J. Balfour ◽  
A. E. Douglas
Keyword(s):  
Absorption Spectrum ◽  
Excited State ◽  
High Resolution ◽  
Potential Energy ◽  
Dissociation Energy ◽  
Ground State ◽  
Potential Energy Curve ◽  
Energy Curve ◽  
Vibrational Constants

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.

The ultraviolet absorption spectrum of the F 2 CN radical

1967 ◽  
Vol 300 (1462) ◽  
pp. 405-414 ◽  
Keyword(s):  
Molecular Structure ◽  
Absorption Spectrum ◽  
Ground State ◽  
Flash Photolysis ◽  
Ultraviolet Absorption ◽  
Ultraviolet Absorption Spectrum ◽  
Rotational Analysis ◽  
Absorption Bands ◽  
New System

A new system of absorption bands near 3600 Å has been observed during the flash photolysis of CF 3 NCF 2 and is ascribed to the free F 2 CN radical. The rotational analysis of the 0–0 band leads to the ground state molecular structure r CF = 1.310 Å (assumed), r CN = 1.265 ± 0.02 Å, FCF angle = 113.5 + 1°. The bands are shown to be type A bands arising from the transition 2 A 1 ← 2 B 2 , and the spectrum is compared with those of the iso-electronic molecules NO 3 and F 2 BO.

Forbidden absorption bands of O2 in the argon continuum region

1969 ◽  
Vol 47 (17) ◽  
pp. 1805-1811 ◽  
Author(s):  
M. Ogawa ◽  
K. R. Yamawaki
Keyword(s):  
Absorption Spectrum ◽  
Ground State ◽  
Electronic States ◽  
Absorption Bands ◽  
Rotational Constants ◽  
Continuum Region

The absorption spectrum of O2 has been photographed in the argon continuum region with a 3-m vacuum spectrograph at a dispersion of 1.42 Å/mm. Based on the known rotational constants of the ground state, the rotational constants of the upper states have been determined for Tanaka progession (I), β–X3Σg−, progression (II), α1Σu+–X3Σ−, and those of a new band at 1144.6 Å. In a brief discussion of the upper electronic states, it is suggested that both the β state and the upper states of the 1144.6 Å band are 3Σu+ states and their electron configurations are (πg2p)(3pπ) and (πg2p)(4pπ), respectively, and also the α state is (πg2p)(3pπ)1Σu+.

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