Laser-excited fluorescence of 15NO2 and N18O2

Measurements are reported of the resonance fluorescence of 15N16O2 and 14N18O2 excited by the 488,496, and 514 nm radiation of an Ar+ laser. The frequency displacements in these spectra are consistent with values calculated previously, using potential constants for the electronic ground state of NO2 derived from the rotational and vibrational constants of NO2 and 15N16O2 but containing no information from N18O2 spectra; the agreement obtained for the latter isotope is therefore a partial test of the potential field.In these spectra, fluorescence occurs from vibronic B2 levels of the Ã2B2 state possessing 7500–8500 cm−1 of vibrational energy. A number of examples are described in which the emission from these vibrationally excited levels shows an anomalous intensity distribution or K-selection rule (e.g., ΔK = ±2) as a result of Coriolis and/or spin–orbit coupling between vibrational levels of the upper electronic state.

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Die Schwingungsfeinstruktur der Elektronenspektren des 13C- und 18O-markierten trans-Dioxotetracyanoosmats (VI),[OsO2(CN)4]2 -

Zeitschrift für Naturforschung A ◽

10.1515/zna-1988-0310 ◽

1988 ◽

Vol 43 (3) ◽

pp. 239-247 ◽

Cited By ~ 11

Author(s):

C. Sartori ◽

W. Preetz

Keyword(s):

Ground State ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Isotopic Shifts ◽

Charge Transfer Transitions ◽

Stretching Vibration ◽

Stretching Vibrations ◽

The One ◽

Franck Condon ◽

Electronic Ground

The electronic absorption spectrum of the solid tetramethyl-ammonium salt of [OsO2(CN)4]2 - is measured at 10 K. The five distinct band systems exhibit vibrational progressions in the range 660-750 cm - 1, corresponding to the Os = O stretching vibrations sometimes coupled with ν(OsC). From this vibrational fine structure the electronic origin is deduced and verified by characteristic isotopic shifts by 18O and 13C. The two bands at lowest energy are assigned to the d-d-transitions 1A1g [b22g] → 3Eg [b12g e1g] (620 - 460 nm) and 1A1g [b22g] → 1Eg [b12g e1g] (490 - 400 nm). The 3Eg state is split by spin-orbit coupling into 5 components, from the one at lowest energy a luminescence emission (830 - 670 nm) takes place with a progression of 860 cm-1, corresponding to the symmetric Os = O stretching vibration in the electronic ground state. The more intense bands are assigned to charge transfer transitions from oxo π-orbitals into unoccupied niveaus of Os (VI): 1A1g [e4u] → 3A2u [e3u e1g] (390 - 340); → 1A1u [e3u e1g] (340 - 290) and → 1Eu [e3u b11g (290 - 230 nm). The singlet-triplet distances are 3200-3600 cm - 1. From a Franck-Condon analysis an excited state elongation of 10-13 pm for the osmyl groups is calculated.

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Laser fluorescence and high vibrational levels of 15NO2

Canadian Journal of Physics ◽

10.1139/p79-116 ◽

1979 ◽

Vol 57 (6) ◽

pp. 828-835 ◽

Cited By ~ 12

Author(s):

J. C. D. Brand ◽

P.-H. Chiu ◽

A. R. Hoy

Keyword(s):

Magnetic Resonance ◽

Ground State ◽

Narrow Band ◽

Laser Fluorescence ◽

Resonance Fluorescence ◽

Infrared Measurements ◽

Vibrational Levels ◽

Vibration Rotation ◽

Laser Magnetic Resonance ◽

Electronic Ground

Resonance fluorescence of 15NO2 excited by narrow-band radiation of an Ar+ laser at 514, 495, 488, and 476 nm is reported and analyzed. The data are combined with published laser magnetic resonance and infrared measurements to obtain a set of vibration and vibration–rotation constants for the electronic ground state of this isotope.The fluorescence bands reported are a-axis polarized, corresponding to a transition moment [Formula: see text] between 2B2 and 2A1 basis states. Numerous anomalies in the vibrational and rotational structure of the fluorescence indicate that, in the region of the manifold probed by the laser, vibrational levels of the parent 2B2 basis state mix extensively with one another as well as with high vibrational levels of the 2A1 ground state.

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The study of energy transfer by kinetic spectroscopy I. The production of vibrationally excited oxygen

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1956.0003 ◽

1956 ◽

Vol 233 (1195) ◽

pp. 455-464 ◽

Cited By ~ 68

Keyword(s):

Flash Photolysis ◽

Vibrational Energy ◽

Vibrationally Excited ◽

Near Resonance ◽

Vibrational Levels ◽

Great Excess ◽

First Time ◽

Kinetics Of ◽

Excited Oxygen ◽

Electronic Ground

The flash photolysis of chlorine dioxide or of nitrogen dioxide in a great excess of inert gasyields oxygen molecules in their electronic ground states with up to eight quanta of vibrational energy. By a study of the reaction kinetics of the two systems, it is concluded that these excited molecules have their origin in the reactions O + NO 2 = NO + O 2 and O + CIO 2 = CIO + O 2 respectively. Thus, for the first time we have available a very convenient method of studying the collisional transfer and degradation of vibrational energy from molecules in the higher vibrational levels of the ground state and some preliminary measurements of the efficiency of deactivation by various molecules are given. It is concluded that the energy is removed most readily either when there is near resonance of the vibrational levels with those of the oxygen, or by free radicals. Some of the reactions of the chlorine oxides present are also discussed.

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Spin-Orbit Coupling Controlled J=3/2 Electronic Ground State in 5d3 Oxides

Physical Review Letters ◽

10.1103/physrevlett.118.207202 ◽

2017 ◽

Vol 118 (20) ◽

Cited By ~ 20

Author(s):

A. E. Taylor ◽

S. Calder ◽

R. Morrow ◽

H. L. Feng ◽

M. H. Upton ◽

...

Keyword(s):

Ground State ◽

Electronic Ground State ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Electronic Ground

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First principles calculations of the structural, electronic, magnetic, and thermodynamic properties of the Nd2MgGe2 and Gd2MgGe2 intermetallic compounds

Scientific Reports ◽

10.1038/s41598-021-89042-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

S. Menouer ◽

O. Miloud Abid ◽

A. Benzair ◽

A. Yakoubi ◽

H. Khachai ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermodynamic Properties ◽

Ground State ◽

First Principles ◽

Essential Role ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Rare Earth Compounds ◽

First Principles Calculations ◽

Antiferromagnetic Ground State

AbstractIn recent years the intermetallic ternary RE2MgGe2 (RE = rare earth) compounds attract interest in a variety of technological areas. We therefore investigate in the present work the structural, electronic, magnetic, and thermodynamic properties of Nd2MgGe2 and Gd2MgGe2. Spin–orbit coupling is found to play an essential role in realizing the antiferromagnetic ground state observed in experiments. Both materials show metallicity and application of a Debye-Slater model demonstrates low thermal conductivity and little effects of the RE atom on the thermodynamic behavior.

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THE LYMAN BANDS OF MOLECULAR HYDROGEN

Canadian Journal of Physics ◽

10.1139/p59-070 ◽

1959 ◽

Vol 37 (5) ◽

pp. 636-659 ◽

Cited By ~ 269

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.

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