The 3300 Å band system of cyclobutanone

1969 ◽  
Vol 47 (11) ◽  
pp. 1235-1236 ◽  
Author(s):  
D. C. Moule
Keyword(s):  
High Resolution ◽  
Electronic State ◽  
Potential Function ◽  
Band System ◽  
Ultraviolet Spectrum ◽  
Vibrational Levels ◽  
Minimum Potential

The ultraviolet spectrum of cyclobutanone vapor has been recorded under conditions of high resolution. The oxygen wagging vibrational levels have been found to be strongly anharmonic in the 1A2 electronic state and have been fitted to a double minimum potential function.

THE 1600 Å BAND SYSTEM OF AMMONIA

1961 ◽  
Vol 39 (4) ◽  
pp. 479-501 ◽  
Author(s):  
A. E. Douglas ◽  
J. M. Hollas
Keyword(s):  
Excited State ◽  
High Resolution ◽  
Electronic State ◽  
Band System ◽  
Excited Electronic State ◽  
Degenerate State ◽  
Coriolis Interaction ◽  
Plane Vibration ◽  
Vibrational Levels ◽  
Out Of Plane

The progression of ammonia bands which extends from 1689 to 1400 Å has been photographed in absorption at high resolution. Six bands have been analyzed and found to be of the perpendicular type. The analysis shows that the molecule is planar in the excited state and that vibrational levels observed in the progression are those of the out-of-plane vibration. The excited electronic state is of the E′′ type. In addition to the normal Coriolis interaction of the degenerate levels, a second effect has been observed which behaves like the Coriolis interaction recently described as 'giant l-type doubling' by Garing, Nielsen, and Rao. No clear evidence has been found for any distortion of the degenerate state from D3h symmetry.

The D2Σ+ – A2Πi and C2Πr – A2Πi transitions of AlO

1985 ◽  
Vol 63 (9) ◽  
pp. 1162-1172 ◽  
Author(s):  
M. Singh ◽  
M. D. Saksena
Keyword(s):  
High Resolution ◽  
Electronic State ◽  
Rotational Structure ◽  
Rotational Constants ◽  
Vibrational Levels ◽  
Lower Electronic State ◽  
The Common ◽  
First Time

Several bands of the D2Σ+ – A2Πi and C2Πr – A2Πi transitions of AlO have been photographed at high resolution and analyzed for the rotational structure. Rotational structure in the vibrational levels ν = 0, 1, 2, 3, and 4 of the common lower electronic state A2Πi has been investigated for the first time. Rotational perturbations have been observed in the A2Πi state. The equilibrium rotational constants of the A2Πi state are Be = 0.53705 cm−1 and αe = 0.00491 cm−1.

The Electronic Spectrum of HF. I. The B1Σ+–X1Σ+ Band System

1973 ◽  
Vol 51 (4) ◽  
pp. 434-445 ◽  
Author(s):  
G. Di Lonardo ◽  
A. E. Douglas
Keyword(s):  
Absorption Spectrum ◽  
High Resolution ◽  
Emission Spectrum ◽  
Electronic Spectrum ◽  
Dissociation Energy ◽  
Band System ◽  
Vibrational Levels ◽  
Internuclear Distances ◽  
X State ◽  
Potential Curves

The electronic emission and absorption spectrum of HF has been photographed at high resolution with a 10 m grating spectrograph. The emission, which extends from 2670 to 1480 Å, consists entirely of bands of the B1Σ+–X1Σ+ (previously denoted as the V1Σ+–X1Σ+)system. From the analysis of 51 bands of the emission spectrum, constants of the vibrational levels of the X state from ν = 7 and 19 and of the B state from ν = 0 to 10 have been determined. The dissociation energy of HF has been found to be D0(HF) = 47 333 ± 60 cm−1. In the absorption spectrum, 56 bands of the B–X system have been identified. Vibrational levels of the B state between ν = 14 and 26 were found to be well behaved and readily analyzed, but levels between ν = 26 and 73 were found to be highly perturbed. Rydberg–Klein–Rees potential curves have been calculated for the B and X states and it is shown that at large internuclear distances the bonding of the B state is almost entirely ionic.

The 3A2 state of thiocarbonyl difluoride

1970 ◽  
Vol 48 (16) ◽  
pp. 2623-2625 ◽  
Author(s):  
D. C. Moule
Keyword(s):  
High Resolution ◽  
Potential Function ◽  
Electronic Transition ◽  
Band System ◽  
Out Of Plane

The 4500 Å band system of thiocarbonyl difluoride F2CS has been photographed under conditions of moderately high resolution and has been assigned to the activity of the v1, v2, v3, and v4 modes arising from the 3A2 ← 1A1 electronic transition. The out-of-plane wagging levels were found to be strongly anharmonic, the observed inversion doubling indicating that the maximum in the potential function was greater than 3100 cm−1.

THE ABSORPTION SPECTRUM OF CF2

1967 ◽  
Vol 45 (7) ◽  
pp. 2355-2374 ◽  
Author(s):  
C. Weldon Mathews
Keyword(s):  
Absorption Spectrum ◽  
Electronic State ◽  
Ground State ◽  
Band System ◽  
Electronic States ◽  
Vibrational Structure ◽  
Rotational Structure ◽  
Transition Moment ◽  
High Dispersion ◽  
Parallel Type

The absorption spectrum of CF2 in the 2 500 Å region has been photographed at high dispersion, and the rotational structure of a number of bands has been analyzed. The analysis of the well-resolved subbands establishes that these are perpendicular- rather than parallel-type bands, as previously assigned. Further analysis shows that the upper and lower electronic states are of 1B1 and 1A1symmetries respectively, corresponding to a transition moment that is perpendicular to the plane of the molecule. In the upper electronic state, r0(CF) = 1.32 Å and [Formula: see text], while in the ground state, r0(CF) = 1.300 Å and [Formula: see text]. An investigation of the vibrational structure of the band system has shown that the vibrational numbering in ν2′ must be increased by one unit from earlier assignments, thus placing the 000–000 band near 2 687 Å (37 220 cm−1). A search between 1 300 and 8 500 Å showed two new band systems near 1 350 and 1 500 Å which have been assigned tentatively to the CF2 molecule.

scholarly journals THE HIGH-RESOLUTION EXTREME-ULTRAVIOLET SPECTRUM OF N2 BY ELECTRON IMPACT

2014 ◽  
Author(s):  
Alan Heays ◽  
Stephen Gibson ◽  
Brenton Lewis ◽  
Alejandro Aguilar ◽  
Joe Ajello
Keyword(s):  
High Resolution ◽  
Electron Impact ◽  
Extreme Ultraviolet ◽  
Ultraviolet Spectrum

The b1Σ+–X3Σ− band system of SO

1968 ◽  
Vol 46 (13) ◽  
pp. 1539-1546 ◽  
Author(s):  
R. Colin
Keyword(s):  
High Resolution ◽  
Microwave Discharge ◽  
Band System ◽  
Rotational Constants

The 0–0, 1–1, 2–2, and 0–1 bands of the b1Σ+–X3Σ− transition of the SO molecule have been observed in the afterglow produced when COS + O2 is pumped rapidly through a microwave discharge. The two strongest bands, 0–0 and 1–1, which lie respectively at 9549.08 and 9626.13 Å, have been photographed at high resolution and have been analyzed. Using the known X3Σ− rotational constants, the vibrational and rotational constants of the 1Σ+ state (Tc = 10 509.97 cm−1) have been determined: ωc′ = 1067.66 cm−1, Bc′ = 0.70262 cm−1, and rc′ = 1.5005 Å. Rotational intensity distributions for 1Σ+–3Σ− transitions are discussed. The a1Δ state of SO is predicted to lie at T ~ 6350 cm−1.

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.

Vibrational Analysis of the 2800 Å Band System of para-Dibromobenzene

1972 ◽  
Vol 50 (12) ◽  
pp. 1402-1408 ◽  
Author(s):  
S. M. Japar
Keyword(s):  
Excited State ◽  
High Resolution ◽  
Ground State ◽  
Band System ◽  
Vibrational Analysis ◽  
Type A ◽  
Strong Type ◽  
Type B ◽  
Sequence Structure ◽  
Extensive Sequence

The 2800 Å band system of p-dibromobenzene has been photographed under high resolution and an extended vibrational analysis has been carried out. The analysis is not inconsistent with the assignment of the system to a 1B2u ← 1Ag transition, by analogy with other p-dihalogenated benzenes. The observed spectrum can be explained in terms of a number of strong type-B vibronic bands and a considerably smaller number of type-A vibronic bands. The extensive sequence structure is adequately accounted for, and can be related to observations on other halogenated benzene molecules. Thirteen ground state and nine excited state fundamental vibrational frequencies have been assigned.

VUV electronic state spectroscopy of 1,1-difluoroethene and difluorochloromethane by high resolution synchrotron radiation

2006 ◽  
Vol 8 (41) ◽  
pp. 4766-4772 ◽  
Author(s):  
P. Limão-Vieira ◽  
Eva Vasekova ◽  
B. N. Raja Sekhar ◽  
N. J. Mason ◽  
S. V. Hoffmann
Keyword(s):  
High Resolution ◽  
Synchrotron Radiation ◽  
Electronic State
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