CN Emission in Active Nitrogen. II. The Role of Energy Transfer and Atom Transfer Reactions in CN(X2Σ+) Excitation

1972 ◽  
Vol 50 (16) ◽  
pp. 2527-2536 ◽  
Author(s):  
G. M. Provencher ◽  
D. J. McKenney
Keyword(s):  
Energy Transfer ◽  
Ground State ◽  
Absolute Intensity ◽  
Vibrationally Excited ◽  
Active Nitrogen ◽  
Band Emission ◽  
Electronically Excited ◽  
Order Of Magnitude ◽  
Three Body ◽  
A Minor

A simplified mechanism is presented for excitation of ground state CN(X2Σ+) formed from carbonaceous impurity in flowing N2 subjected to a microwave discharge. Analysis of absolute intensity data from spectrometer recordings of CN(B2Σ+ → X2Σ+) violet band emission enabled order of magnitude estimates of rate constants for CN(X2Σ+) excitation by energy transfer from vibrationally excited ground state nitrogen, [Formula: see text][Formula: see text]and formation of electronically excited NCN* in a three body reaction[Formula: see text]Energy transfer from [Formula: see text] is shown to be a minor source of excitation of CN to radiative levels. N2(A) is a source of vibrationally excited ground state nitrogen, [Formula: see text] which in turn excites CN. Vibrational population profiles under all conditions in this work are shown to be primarily a function of [Formula: see text] Evidence for the participation of the A2Π state of CN is shown in the population maxima at ν = 4 and 10 of the B2Σ+ state.

The Dielectric Discharge as an Efficient Generator of Active Nitrogen for Chemiluminescence and Analysis

1983 ◽  
Vol 37 (6) ◽  
pp. 545-552 ◽  
Author(s):  
John Kishman ◽  
Eric Barish ◽  
Ralph Allen
Keyword(s):  
Gas Phase ◽  
Ground State ◽  
Band System ◽  
Electrothermal Atomization ◽  
Characteristic Radiation ◽  
Gaseous Species ◽  
Vibrationally Excited ◽  
Active Nitrogen ◽  
Excited Species ◽  
Intense Emission

A predominantly blue “active nitrogen” afterglow was generated in pure flowing nitrogen or in air by using a dielectric discharge at pressures from 1 to 20 Torr. The afterglow contains triplet state molecules and vibrationally excited ground state molecules. These species are produced directly by electron impact without the formation and recombination of nitrogen atoms. The most intense emission is the N2 second positive band system. The N2 first positive and N2+ first negative systems are also observed. The spectral and electrical properties of this discharge are discussed in order to establish guidelines for the analytical use of the afterglow for chemiluminescence reactions. The metastatic nitrogen efficiently transfers its energy to atomic and molecular species which are introduced into the gas phase and these excited species emit characteristic radiation. The effects of electrothermal atomization of Zn and the introduction of gaseous species (e.g., NO) on the afterglow are described.

THE REACTIVE COMPONENTS IN ACTIVE NITROGEN AND THE ROLE OF SPIN CONSERVATION IN ACTIVE NITROGEN REACTIONS

1956 ◽  
Vol 34 (9) ◽  
pp. 1217-1231 ◽  
Author(s):  
H. G. V. Evans ◽  
C. A. Winkler
Keyword(s):  
Experimental Information ◽  
Active Species ◽  
Convincing Evidence ◽  
Critical Examination ◽  
Vibrationally Excited ◽  
Active Nitrogen ◽  
Electronically Excited ◽  
Excited Molecules ◽  
Triatomic Radicals

Critical examination of the available experimental information provides rather convincing evidence that atomic nitrogen is the main reactive species in active nitrogen. It appears quite unlikely that a significant contribution to the activity is made by electronically excited molecules, metastable atoms, ions, or triatomic radicals. Evidence exists, however, for the presence of more than one active species, and a plausible suggestion would seem to be that the second species is vibrationally excited molecules. Consideration of the role of spin conservation in reactions of active nitrogen leads to the conclusion that reactions that conserve spin occur more readily than those in which spin is not conserved.

Kinetics of reactions involving CN emission III. The excitation of CN in active nitrogen

1968 ◽  
Vol 305 (1480) ◽  
pp. 93-105 ◽  
Keyword(s):  
Ground State ◽  
Blue Emission ◽  
Absolute Intensity ◽  
Active Species ◽  
Active Nitrogen ◽  
System A ◽  
Vibrational Levels ◽  
Similar Quantity ◽  
Kinetics Of ◽  
Cn Radicals

The presence of carbonaceous impurities in active nitrogen causes strong blue CN emission from levels of the B 2 ∑ + state up to v ' = 15. The kinetics of this emission have been studied, and the concentrations of CN radicals measured by electronic absorption spectroscopy, in systems where the blue emission was induced by adding traces of methane before the discharge, or a similar quantity of acetylene after the discharge and examining the system a long way downstream. CN is shown to be excited by energetic species formed in nitrogen atom recombination. The absolute intensity of the emission and its kinetics suggest that lower vibrational levels of the metastable A 3 ∑ + state of N 2 are mainly responsible, but the kinetics of quenching by ammonia and water for nitrogen and argon carriers show that an additional active species is present, probably N 2 in high vibrational levels of the ground state.

ELECTRIC DIPOLE POLARIZABILITIES OF THE TRITON AND LAMBDA HYPERTRITON

2010 ◽  
Vol 19 (02) ◽  
pp. 225-242 ◽  
Author(s):  
V. F. KHARCHENKO ◽  
A. V. KHARCHENKO
Keyword(s):  
Experimental Data ◽  
Wave Function ◽  
Electric Dipole ◽  
Ground State ◽  
Input Data ◽  
Low Energy ◽  
Dipole Polarizability ◽  
Order Of Magnitude ◽  
Three Body ◽  
Dipole Polarizabilities

A rigorous formalism for determining the electric dipole polarizability of a three-hadron bound complex in the case that the system has only one bound (ground) state has been elaborated. On its basis, by applying a model wave function that takes into account specific features of the structure of the three-body nuclei and using the known low-energy experimental data for the p–n, n–d, and Λ–d systems as input data, we have calculated the values of the electric dipole polarizabilities of the triton αE(3 H ) and lambda hypertriton [Formula: see text]. We have obtained for the triton polarizability the value 0.23 fm3. It follows from our study that the polarizability of the lambda hypertriton is close to 3 fm3 exceeding the polarizabilities of the ordinary three-nucleon nuclei by an order of magnitude.

Spectroscopic study of the reaction of active nitrogen with some organometallic compounds

1967 ◽  
Vol 45 (16) ◽  
pp. 1891-1896 ◽  
Author(s):  
R. E. March ◽  
H. I. Schiff
Keyword(s):  
Energy Transfer ◽  
Spectroscopic Study ◽  
Organometallic Compounds ◽  
Initial Energy ◽  
Emission Lines ◽  
Kcal Mole ◽  
Vibrationally Excited ◽  
Active Nitrogen ◽  
Metal Atoms

Transfer of energy from constituents in active nitrogen to gaseous organometallic compounds leads to dissociation of the organometallic and excitation of CN and (or) metal atom. Organometallic compounds of aluminium, zinc, and boron were used in this investigation. The observed emission lines from metal atoms and highly vibrationally excited CN correspond to an initial energy transfer in excess of 200 kcal/mole. The possible role of N2(5Σg+) molecules as excitors is discussed in the light of the results obtained.

Vibrationally Excited Ground‐State Nitrogen in Active Nitrogen

1958 ◽  
Vol 28 (3) ◽  
pp. 510-511 ◽  
Author(s):  
Frederick Kaufman ◽  
John R. Kelso
Keyword(s):  
Ground State ◽  
Vibrationally Excited ◽  
Active Nitrogen

ELEMENTARY PROCESSES IN THE DECOMPOSITION OF OZONE

1962 ◽  
Vol 40 (3) ◽  
pp. 539-544 ◽  
Author(s):  
D. J. McKenney ◽  
K. J. Laidler
Keyword(s):  
Potential Energy ◽  
Ground State ◽  
Potential Energy Surfaces ◽  
Visible Radiation ◽  
Vibrationally Excited ◽  
Elementary Processes ◽  
Body Complex ◽  
Three Body ◽  
Energy Surfaces ◽  
Excited Oxygen

Potential-energy surfaces are considered for the O4 complex, treated as the three-body complex O … O … O2. By means of these it is shown that O(3P) reacting with O3 may give rise to a molecule of O2 in its ground state and one in any of the states 3Σg− (ground), 1Δg, and 1Σg+; 3Σu+ cannot be produced. Most of the oxygen molecules produced are expected to be in the ground electronic state, but will be vibrationally excited. Such molecules are readily deactivated and unlikely to lead to energy chains by the reaction[Formula: see text]Such chains are therefore unlikely in the thermal decomposition and in that initiated by visible radiation. In ultraviolet light O(1D) atoms are produced and the potential-energy surfaces show that these give rise very efficiently to O(1D) + O3 → O2 + O2(3Σu−); the latter have 141 kcal in excess of the ground state. It is suggested that the subsequent radiative process[Formula: see text]is responsible for sustaining the population of vibrationally excited oxygen molecules in the ground state and that these propagate energy chains, as postulated by McGrath and Norrish (1). The significance of these conclusions is discussed with reference to the experimental evidence.

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