Emission spectrum of the PO molecule. I. A new B′2Πi–X2Πr transition

1970 ◽  
Vol 48 (20) ◽  
pp. 2391-2398 ◽  
Author(s):  
R. D. Verma
Keyword(s):  
Emission Spectrum ◽  
Ground State ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
New System

A new system of the PO molecule in the region 4800–3800 Å has been obtained. Rotational analysis of its seven bands establishes the transition involved to be B′2Πi–X2Πr, where X2Πr is the known ground state of the molecule. The molecular constants of the lower and upper levels have been evaluated.

Rotational Analysis of the lΠ–XlΣ+ System of C80Se

1974 ◽  
Vol 52 (9) ◽  
pp. 813-820 ◽  
Author(s):  
René Stringat ◽  
Jean-Paul Bacci ◽  
Marie-Hélène Pischedda
Keyword(s):  
Emission Spectrum ◽  
Ground State ◽  
High Frequency ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
High Frequency Discharge ◽  
Perturbed State ◽  
Simple Evaluation ◽  
Π State

The strongly perturbed 1Π–X1Σ+ system of C80Se has been observed in the emission spectrum of a high frequency discharge through selenium and carbon traces in a neon atmosphere. The analysis of five bands yields, for the molecular constants of the ground state, the values Be″ = 0.5750 cm−1, [Formula: see text], αe″ = 0.00379 cm−1, re″ = 1.676 Å, ΔG″(1/2) = 1025.64 cm−1, and ΔG″(3/2) = 1015.92 cm−1. The numerous perturbations in the 1Π state prohibit the simple evaluation of the constants of the perturbed state and of the perturbing ones.

The Emission Spectrum of PtO between 3800 and 4500 Å

1975 ◽  
Vol 53 (19) ◽  
pp. 1991-1999 ◽  
Author(s):  
Rosemary Scullman ◽  
Ulf Sassenberg ◽  
Christer Nilsson
Keyword(s):  
Emission Spectrum ◽  
Ground State ◽  
Lower State ◽  
Vibrational Levels ◽  
New System

A new system belonging to the emission spectrum of PtO has been found in the region of 3800–4500 Å. This system has the earlier known X1Σ ground state as the lower state and a hitherto unknown 1Σ state, here designated the D1Σ state, as the upper state. The four lowest vibrational levels of the D1Σ state were rotationally analyzed. Of these levels, the [Formula: see text] level seems to be unperturbed although the v′ = 1, 2, and 3 levels are strongly perturbed.

Spectrum of AsS. I. Analysis of the A′2Π3/2–X2Π3/2 Band System

1971 ◽  
Vol 49 (10) ◽  
pp. 1249-1254 ◽  
Author(s):  
Midori Shimauchi
Keyword(s):  
High Resolution ◽  
Emission Spectrum ◽  
Ground State ◽  
Band System ◽  
Vibrational Analysis ◽  
Quartz Tube ◽  
Rotational Analysis ◽  
Vibrational Constants

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.

The electronic emission spectrum of triatomic hydrogen. I. Parallel bands of H3 and D3 near 5600 and 6025 Å

1980 ◽  
Vol 58 (8) ◽  
pp. 1238-1249 ◽  
Author(s):  
I. Dabrowski ◽  
G. Herzberg
Keyword(s):  
Interstellar Medium ◽  
Emission Spectrum ◽  
Detailed Analysis ◽  
Ground State ◽  
Emission Band ◽  
Rydberg States ◽  
Electronic States ◽  
Molecular Constants ◽  
Additional Band ◽  
Rydberg Electron

A spectrum of triatomic hydrogen and deuterium was first discovered by means of an emission band with diffuse rotational structure near 5600 Å. An additional band of similar but much better resolved structure was subsequently observed near 6025 Å. The detailed analysis of these two bands for both H3 and D3 is described in this paper. Both bands are [Formula: see text] bands of a symmetric top; their structure establishes beyond doubt that triatomic hydrogen has a D3h structure in its Rydberg states. The molecular constants in upper and lower states are close to those in the ground state of H3+ (or D3+) in accordance with the assumption that these states are Rydberg states in which a single electron moves around a H3+ or D3+ core. The predicted states of such a Rydberg electron in a field of D3h symmetry account very well for the observed electronic states, both those involved in the [Formula: see text] bands described here and those involved in the [Formula: see text] bands to be discussed in subsequent papers of this series. The lowest state of the Rydberg electron 2p2E′ is unstable and dissociates to H2 + H in their ground states. It is this state that causes predissociation in the two lower states 2s2A1′and 2p2A2″ of the two [Formula: see text] bands here under discussion. The predissociation of 2s2A1′ is vibronically allowed and fairly strong such that all lines have widths of about 7 cm−1 for D3 and 30 cm−1 for H3. The predissociation of the 2p2A2″ state is vibronically forbidden and occurs only on account of ro-vibronic interaction. H3+ ions are assumed to be present in the interstellar medium. When they recombine with electrons they must necessarily emit the spectra described in this series of papers.

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.

Rotational Analysis of Bands of the Transition of PH2

1972 ◽  
Vol 50 (19) ◽  
pp. 2265-2276 ◽  
Author(s):  
J. M. Berthou ◽  
B. Pascat ◽  
H. Guenebaut ◽  
D. A. Ramsay
Keyword(s):  
Excited State ◽  
Ground State ◽  
Electronic Transition ◽  
Rotational Analysis ◽  
Empirical Formulas ◽  
Molecular Constants ◽  
Vibrational Levels

Rotational analyses have been carried out for the 0ν′20–000 bands of the [Formula: see text] electronic transition of PH2 with ν′2 = 1–8. Approximately 1000 lines have been assigned. The earlier analysis of the 000–000 band has been extended and improved molecular constants obtained. The Hamiltonian used for this band does not fit the excited state levels with [Formula: see text]. Term values are therefore given for all observed levels. Empirical formulas are presented which give approximate fits to the higher levels. Numerous rotational perturbations are found in the excited state. Perturbations up to 0.6 cm−1 are also found in the 000 level of the excited state. These latter perturbations can only be caused by the higher vibrational levels of the ground state.

The electronic spectrum of the CS+ molecular ion: rotational analysis and perturbation effects in the A2Πi–X2Σ+ transition

1978 ◽  
Vol 56 (5) ◽  
pp. 587-600 ◽  
Author(s):  
D. Gauyacq ◽  
M. Horani
Keyword(s):  
Carbon Disulfide ◽  
Ground State ◽  
Valence Electron ◽  
Band System ◽  
Local Perturbation ◽  
Rotational Analysis ◽  
Molecular Constants ◽  
Molecular Ion ◽  
Vibrational Levels ◽  
The Difference

A new emission spectrum in the red region (6000–8000 Å) has been recorded from a low pressure hot cathode discharge through carbon disulfide. This band system has been assigned to the A2Πi–X2Σ+ transition of the CS+ molecular ion on the basis of the rotational analysis and comparison with other nine valence-electron molecules. Molecular constants have been obtained by direct least squares fits of the line frequencies to the difference of the eigenvalues of standard 2Π and 2Σ+ matrices.A local perturbation in the A2Πi (ν = 5) state has been studied quantitatively. The position of the perturbing vibrational level in the X2Σ+ state has been determined within a few centimetre−1. This study gave a consistent set of molecular constants for the ground state of CS+ and allowed a partial deperturbation treatment of the observed vibrational levels of the excited A2Πi state.Numerous bands are also observed in the 4000 Å region. A discussion is given concerning the possible assignment of bands at 4059 and 4110 Å to the CS+B2Σ+–A2Πi (0,0) transition.

Further results relating to the electronic spectrum of 175Lu16O

1986 ◽  
Vol 64 (3) ◽  
pp. 246-251 ◽  
Author(s):  
A. Bernard ◽  
C. Effantin
Keyword(s):  
Least Squares ◽  
Electronic Spectrum ◽  
Ground State ◽  
Rotational Analysis ◽  
Least Squares Fitting ◽  
Fitting Procedure ◽  
Vibrational Levels ◽  
Unique Band ◽  
Π State ◽  
New System

Further results are presented concerning the three known systems of the molecule LuO; i.e., A2Π, B2Π, C2Σ+ → X2Σ+. The observed wavenumbers in each of the 12 analyzed bands are reduced using an iterative, least squares fitting procedure. Rotational constants are given for vibrational levels ν = 0 and 1 in the C state and up to ν = 7 in the X and B states. The 1–1 band of the A → X system is partly analyzed. These new calculations confirm level B to be the 3/2 component of a 2Π state; but they give no such confirmation for the identification of the A level, whose 2Π nature is well established, as the 1/2 component of the same state.Moreover, a unique band at 5120 Å that cannot be classified into any of the three known systems is described and attributed to a new system of LuO. A partial rotational analysis is made showing that the band corresponds to a transition involving the level ν = 0 in the ground state. The nature of the upper state is discussed.

The Ground State and A2Π Excited State of Magnesium Deuteride

1975 ◽  
Vol 53 (15) ◽  
pp. 1477-1482 ◽  
Author(s):  
Walter J. Balfour ◽  
Hugh M. Cartwright
Keyword(s):  
Excited State ◽  
High Resolution ◽  
Emission Spectrum ◽  
Isotope Effect ◽  
Ground State ◽  
Visible Emission ◽  
Molecular Constants ◽  
Dissociation Energies ◽  
First Time ◽  
Π State

The visible emission spectrum of MgD has been reexamined at high resolution. Published analyses of the A2Π → X2Σ+ system have been extended and the data have been combined with observations in the B′2Σ+ → X2Σ+ system to provide information on the ground state levels ν = 3, 4, 5, and 6 for the first time. The following molecular constants (in cm−1) have been determined—for the A2Π state: ωc = 1154.75, ωcxc = 16.675, Bc = 3.2190, Dc = 9.64 × 10−5 and for the X2Σ+ state: ωc = 1077.71, ωcxc = 15.92, Bc = 3.0306, and Dc = 9.39 × 10−5. The dissociation energies in the A2Π and X2Σ+ states have been estimated to be ~ 15 500 cm−1 and ~ 11 500 cm−1 respectively. The MgH/MgD isotope effect and the Λ doubling in the A2Π state are discussed.

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