The emission spectrum of ReO between 375 and 875 nm: A classification based on rotational analysis and Re16O/Re18O isotope shifts

1984 ◽  
Vol 62 (12) ◽  
pp. 1524-1537 ◽  
Author(s):  
Walter J. Balfour ◽  
Ram. S. Ram
Keyword(s):  
High Resolution ◽  
Emission Spectrum ◽  
Electronic States ◽  
Electronic Transitions ◽  
Lower State ◽  
Rotational Analysis ◽  
Isotope Shifts ◽  
Isotopic Shifts

The emission spectrum of the ReO molecule has been photographed under high resolution between 375 and 875 nm. In addition to the 711.9 and 404.5 nm systems previously studied a large number of new electronic transitions have been classified on the basis of Re16O/Re18O isotopic shifts. The rotational structures of 18 bands of Re16O and 1 band of Re18O have been analyzed. Two low-lying electronic states in addition to the known common lower state of the 711.9 and 404.5 nm systems have been identified.

A 4Σ−–2Π TRANSITION OF THE SiF MOLECULE

1962 ◽  
Vol 40 (5) ◽  
pp. 586-597 ◽  
Author(s):  
R. D. Verma
Keyword(s):  
High Resolution ◽  
Ground State ◽  
Electronic States ◽  
Lower State ◽  
Rotational Analysis ◽  
Rotational Constants

The η bands of SiF, in the region 3300–3400 Å, have been photographed in emission at high resolution. A detailed rotational analysis has shown that these bands represent a 4Σ−–2Πτ transition. The lower state is the ground state of the molecule. The principal rotational constants of the upper and lower electronic states in cm−1 are as follows:[Formula: see text]A discussion of the electron configurations is also given.

High resolution spectrum of GdO

1976 ◽  
Vol 54 (24) ◽  
pp. 2429-2434 ◽  
Author(s):  
B. R. Yadav ◽  
S. B. Rai ◽  
D. K. Rai
Keyword(s):  
High Resolution ◽  
Emission Spectrum ◽  
Visible Emission ◽  
High Resolution Spectrum ◽  
First Order ◽  
Isotopic Shifts ◽  
Vibrational Constants ◽  
Dc Arc

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.

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.

Infrared and Visible Emission Spectrum of the NO Molecule. The 2Δ–2Π Bands of the 3d–3p and 4d–3p Transitions between Rydberg Complexes

1971 ◽  
Vol 49 (1) ◽  
pp. 76-89 ◽  
Author(s):  
F. Ackermann
Keyword(s):  
High Resolution ◽  
Emission Spectrum ◽  
Rydberg State ◽  
Energy Levels ◽  
Rydberg States ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Rotational Analysis ◽  
Mixed States ◽  
Doublet Splitting

The two mutually related bands B′2Δ–C2Π (7,0) → N2Δ–C2Π (0,0) and N2Δ–C2Π (0,0) → B′2Δ–C2Π (7,0) are observed with high resolution between 6620 and 6520 Å in the emission spectrum of the NO molecule. They are the 2Δ–2Π part of the 4d–3p transitions between the two Rydberg states N2Δ(4dδ) and C2Π (3pπ) of the molecule. A rotational analysis is carried out for both bands, and the very close similarity of the structure of these bands with the structure of the corresponding 2Δ–2Π bands of the 3d–3p transitions, observed in the infrared, is demonstrated. The two upper levels in these nd–3p transitions represent examples of mixed states showing complete changeover with increasing rotation from the Rydberg type with no spin–orbit coupling (AR = 0.00 ± 0.05 cm−1) to an inverted valence type and vice versa. The behavior of the doublet splitting is studied with regard to this changeover. The lower levels of the Rydberg state C2Π also are mixtures with levels of a valence state. The mixing with B2Π (ν = 7) is comparatively small in the C2Π (ν = 0) level, but it strongly affects the energy levels with the lowest J values. The beginning of one of the two bands observed in the visible, therefore, forms the (7,7) band of the system B′2ΔB2Π. Constants of the states involved are determined.

The rotational analysis of the A1Π–X1Σ+ system of Si130Te

1992 ◽  
Vol 70 (5) ◽  
pp. 291-294 ◽  
Author(s):  
Sheila Gopal ◽  
M. Singh ◽  
G. Lakshminarayana
Keyword(s):  
High Resolution ◽  
Emission Spectrum ◽  
Microwave Discharge ◽  
Band System ◽  
Rotational Structure ◽  
Quartz Tube ◽  
Rotational Analysis ◽  
Rotational Constants

The emission spectrum of Si130Te was excited by microwave discharge (2450 MHz) in a sealed quartz tube. The A1Π–X1Σ+ band system (3100–3900 Å) (1 Å = 10−10 m) photographed under high resolution on a 10.6 m Ebert grating spectrograph. The rotational analysis of 32 bands was carried out, which led to the determination of the accurate vibrational and rotational constants. The rotational structure belonging to ν′ > 9 levels appear to be perturbed.

Emission Spectrum of the PO Molecule. Part II.2Σ–2Σ Transitions

1971 ◽  
Vol 49 (24) ◽  
pp. 3180-3200 ◽  
Author(s):  
R. D. Verma ◽  
M. N. Dixit ◽  
S. S. Jois ◽  
S. Nagaraj ◽  
S. R. Singhal
Keyword(s):  
Emission Spectrum ◽  
Ionization Potential ◽  
Dissociation Energy ◽  
Ground State ◽  
Rydberg States ◽  
Electronic States ◽  
Electronic Transitions ◽  
A Value ◽  
Upper Limit ◽  
First Ionization Potential

Rotational structure of emission bands of the PO molecule in the region 5300–3800 Å is analyzed. The spectrum is attributed to 5 electronic transitions A2Σ+–B2Σ+, F2Σ+–B2Σ+, G2Σ+–B2Σ+, H2Σ+–B2Σ+, and I2Σ+–B2Σ+, where F, G, H, and I are the new electronic states and A and B are the upper states of the well-known γ and β bands respectively. Practically all the new 2Σ states are found to be perturbed. A qualitative account of these perturbations together with a deperturbation of certain levels is given. A number of cases of predissociation are also observed. This predissociation is attributed to the presence of 4Πi, and A′2Σ+ states, which dissociate to the ground state atomic products. From this an upper limit of the dissociation energy of the ground state of PO is determined to be D0 = 49 536 cm−1. The A, D, E, G, H, and I states of this molecule are assigned as Rydberg states corresponding to the σ4s, π4p, δ3d, σ4p, σ3d, and σ5s orbitals, respectively. From them a value of 67 570 cm−1 is evaluated for the first ionization potential of PO. All the electronic states established for this molecule are described in terms of electron configurations.

THE ABSORPTION SPECTRUM OF CNC

1966 ◽  
Vol 44 (2) ◽  
pp. 353-372 ◽  
Author(s):  
A. J. Merer ◽  
D. N. Travis
Keyword(s):  
Absorption Spectrum ◽  
Bond Length ◽  
Ground State ◽  
Flash Photolysis ◽  
Electronic States ◽  
Electronic Transitions ◽  
Ultraviolet Absorption Spectrum ◽  
Rotational Analysis ◽  
Bending Vibrations ◽  
Show Evidence

The ultraviolet absorption spectrum of the free CNC radical has been discovered in the flash photolysis of diazoacetonitrile, HC(CN)N2. The identity of the radical has been proved from isotopic evidence, using 15N and 13C, together with rotational analysis of the bands. Rotational analyses have shown that the bands of CNC must be assigned to two electronic transitions, A2Δu–X 2Πg, and [Formula: see text]. The sequence bands in the bending vibrations, which are observed in both electronic transitions, show evidence of Renner–Teller interaction in both the degenerate electronic states: this interaction is extremely large in the X2Πg state. The principal constants (in cm−1) of the observed states of CNC are as follows:[Formula: see text]The C—N bond length in the ground state of CNC is found to be 1.245 Å.CNC is isomeric with CCN, whose spectrum has been reported previously; some interesting comparisons are made between the spectra of these two molecules.

Rotational Structure in Some Higher Excited States of the GeF Molecule

1974 ◽  
Vol 52 (15) ◽  
pp. 1458-1475 ◽  
Author(s):  
R. W. Martin ◽  
A. J. Merer
Keyword(s):  
Emission Spectrum ◽  
Excited States ◽  
Ground State ◽  
Valence State ◽  
Rydberg States ◽  
The Other ◽  
Electronic Transitions ◽  
Lower State ◽  
High Dispersion ◽  
Higher Excited States

The weaker electronic transitions in the region 2000–9000 Å in the emission spectrum of GeF have been photographed at high dispersion; three new transitions with the A2Σ+ state as lower state have been discovered, and the various systems near 2100 and 8600 Å have been reassigned. The spectra have been explained in terms of six excited states lying between 40 000 and 50 000 cm−1 above the ground state, and representative bands involving all six have been analyzed rotationally. Five of these excited states are Rydberg states (5pσ, 5pπ, 4dπ, 4dδ, and 6sσ), and the other is the σπ22Δ valence state; this latter interacts strongly with the 4dδ 2Δ state.

Constantes moléculaires de de NH2 : observation et estimation de la vibration ν3

1982 ◽  
Vol 60 (1) ◽  
pp. 49-55 ◽  
Author(s):  
M. Vervloet ◽  
M. F. Merienne-Lafore
Keyword(s):  
High Resolution ◽  
Emission Spectrum ◽  
Least Squares ◽  
Fluorescence Spectra ◽  
Fermi Resonance ◽  
Rotational Analysis ◽  
Least Squares Fit ◽  
Coriolis Perturbation ◽  
Effective Constants

From the high resolution photographic emission spectrum, a rotational analysis of the [Formula: see text] state of NH2 has been carried out. This analysis was aided by laser excited fluorescence spectra which exhibit some extra lines attributed to a Coriolis perturbation between the rotational levels of (100) and (001), [Formula: see text]. A Fermi resonance has also been observed between (100) and (020), [Formula: see text]. By deleting the perturbed rotational levels from the least squares fit, it has been possible to calculate some effective constants for the [Formula: see text] level with the origin at 3219.36 cm−1. In addition an estimated value of 3280 cm−1 is proposed for the frequency of ν3.

The Ã1A″(S1) excited electronic states of HCN and DCN: Isotopic evidence that unifies experiment and theory

1984 ◽  
Vol 62 (12) ◽  
pp. 1763-1774 ◽  
Author(s):  
G. A. Bickel ◽  
K. K. Innes
Keyword(s):  
High Resolution ◽  
Ab Initio ◽  
Absorption Spectra ◽  
Electronic Transition ◽  
Vacuum Ultraviolet ◽  
Electronic States ◽  
Excited Electronic States ◽  
Isotopic Shifts ◽  
Ab Initio Theory ◽  
First Time

High-resolution vacuum ultraviolet absorption spectra of D13CN and DC15N are photographed, especially for comparison with the so-called β–X system, observed previously for DCN but not for HCN. Isotopic shifts establish the absolute vibrational numbering for this system, yielding its assignment to the [Formula: see text] transition. The measured bands between 53 100 and 65 200 cm−1 are thereby accommodated by a single electronic transition as predicted by ab initio theory. Constants of all three Ã-state vibrations of HCN and each DCN are determined for the first time.

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