scholarly journals Model of daytime emissions of electronically-vibrationally excited products of O<sub>3</sub> and O<sub>2</sub> photolysis: application to ozone retrieval

2006 ◽  
Vol 24 (11) ◽  
pp. 2823-2839 ◽  
Author(s):  
V. A. Yankovsky ◽  
R. O. Manuilova
Keyword(s):  
Atomic Oxygen ◽  
Energy Exchange ◽  
Electronic States ◽  
Vibrational States ◽  
Vibrationally Excited ◽  
Proposed Model ◽  
Vibrational Levels ◽  
Electronically Excited ◽  
Basic Facts ◽  
Kinetics Of

Abstract. The traditional kinetics of electronically excited products of O3 and O2 photolysis is supplemented with the processes of the energy transfer between electronically-vibrationally excited levels O2(a1Δg, v) and O2(b1Σ+g, v), excited atomic oxygen O(1D), and the O2 molecules in the ground electronic state O2(X3Σg−, v). In contrast to the previous models of kinetics of O2(a1Δg) and O2 (b1Σ+g), our model takes into consideration the following basic facts: first, photolysis of O3 and O2 and the processes of energy exchange between the metastable products of photolysis involve generation of oxygen molecules on highly excited vibrational levels in all considered electronic states – b1Σ+g, a1Δg and X3Σg−; second, the absorption of solar radiation not only leads to populating the electronic states on vibrational levels with vibrational quantum number v equal to 0 – O2(b1Σ+g, v=0) (at 762 nm) and O2(a1Δg, v=0) (at 1.27 µm), but also leads to populating the excited electronic–vibrational states O2(b1Σ+g, v=1) and O2(b1Σ+g, v=2) (at 689 nm and 629 nm). The proposed model allows one to calculate not only the vertical profiles of the O2(a1Δg, v=0) and O2(b1Σ

Kinetics of reactions involving CN emission. I. General features of reactions with active nitrogen and atomic oxygen

1965 ◽  
Vol 288 (1413) ◽  
pp. 256-274 ◽  
Keyword(s):  
Atomic Oxygen ◽  
Methylene Chloride ◽  
Transfer Reactions ◽  
Third Body ◽  
Active Nitrogen ◽  
Cyanogen Chloride ◽  
Vibrational Levels ◽  
Electronically Excited ◽  
Kinetics Of

Emission of the CN red (A -> X) and violet (B -> X) systems accompanying the reactions of active nitrogen with cyanogen, hydrogen cyanide, cyanogen chloride and methylene chloride and of oxygen atoms with cyanogen have been investigated. Bayes’s classification of the rod emission into the vibrational distributions P 1 (v' ≤ 3) and P 2 (v' ≥ 3) can be extended to the violet system, emission from levels 15 ≥ v' ≥ 5 accompanying the P 1 distribution and emission from level v' = 0 occurring with the P 2 emission. It is shown that the P 1 distribution and the excitation of the high vibrational levels of the violet system are due to collisions of CN with energetic species or CN acting as a third body for atomic recombination. The P 2 distribution is associated with the formation of electronically excited CN in exothermic transfer reactions such as N + CH = NC + H, N + CCl = NC + Cl

scholarly journals Subauroral red arcs as a conjugate phenomenon: comparison of OV1-10 satellite data with numerical calculations

1997 ◽  
Vol 15 (8) ◽  
pp. 984-998 ◽  
Author(s):  
A. V. Pavlov
Keyword(s):  
Electron Density ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Atomic Oxygen ◽  
Major Ions ◽  
Integral Intensity ◽  
Rate Coefficients ◽  
Vibrationally Excited ◽  
Vibrational Distribution ◽  
Vibrational Levels

Abstract. This study compares the OV1-10 satellite measurements of the integral airglow intensities at 630 nm in the SAR arc regions observed in the northern and southern hemisphere as a conjugate phenomenon, with the model results obtained using the time-dependent one-dimensional mathematical model of the Earth ionosphere and plasmasphere (the IZMIRAN model) during the geomagnetic storm of the period 15–17 February 1967. The major enhancements to the IZMIRAN model developed in this study are the inclusion of He+ ions (three major ions: O+, H+, and He+, and three ion temperatures), the updated photochemistry and energy balance equations for ions and electrons, the diffusion of NO+ and O2+ ions and O(1D) and the revised electron cooling rates arising from their collisions with unexcited N2, O2 molecules and N2 molecules at the first vibrational level. The updated model includes the option to use the models of the Boltzmann or non-Boltzmann distributions of vibrationally excited molecular nitrogen. Deviations from the Boltzmann distribution for the first five vibrational levels of N2 were calculated. The calculated distribution is highly non-Boltzmann at vibrational levels v > 2 and leads to a decrease in the calculated electron density and integral intensity at 630 nm in the northern and southern hemispheres in comparison with the electron density and integral intensity calculated using the Boltzmann vibrational distribution of N2. It is found that the intensity at 630 nm is very sensitive to the oxygen number densities. Good agreement between the modelled and measured intensities is obtained provided that at all altitudes of the southern hemisphere a reduction of about factor 1.35 in MSIS-86 atomic oxygen densities is included in the IZMIRAN model with the non-Boltzmann vibrational distribution of N2. The effect of using of the O(1D) diffusion results in the decrease of 4–6% in the calculated integral intensity of the northern hemisphere and 7–13% in the calculated integral intensity of the southern hemisphere. It is found that the modelled intensities of the southern hemisphere are more sensitive to the assumed values of the rate coefficients of O+(4S) ions with the vibrationally excited nitrogen molecules and quenching of O+(2D) by atomic oxygen than the modelled intensities of the northern hemisphere.

The measurement of rapid rate processes by kinetic spectroscopy during a photolysis flash; vibrational relaxation of NO X 2 II from levels v 2

1972 ◽  
Vol 328 (1575) ◽  
pp. 515-527 ◽  
Keyword(s):  
Optical Density ◽  
Vibrational Relaxation ◽  
Energy Exchange ◽  
Vibrational Energy ◽  
Excited Level ◽  
Vibrational Levels ◽  
Order Of Magnitude ◽  
Rate Processes ◽  
Kinetics Of ◽  
Good Agreement

The recording of transient changes in optical density that take place during the period of a photolysis flash can, in principle, allow measurement of the kinetics of photo-processes having half-lives an order of magnitude less than the rise or decay time of the flash itself. The construction and use of a sensitive, ‘split-beam’ kinetic spectrophotometer is described, which permits the detection of transient changes in optical density > 0.01 and the measurement of half-lives >1 (us. The apparatus has been used to study the relaxation of NOX 2 II from its first and second excited vibrational levels in the presence of N 2 0 or CH4 and/or Ar. The efficiency of vibrational energy exchange with N 2 0 decreases with the vibrational quantum number of the excited level and this is shown to be consistent with the reduction in the vibrational spacing caused by anharmonicity. The measured collision numbers are in good agreement with those calculated on the baste of an empirical correlation (Callear 1965).

Nascent HF† and HSO(2A′) formations in the elementary reactions of F + H2S and HS + O3 and the internal energy distributions

1995 ◽  
Vol 73 (2) ◽  
pp. 204-211 ◽  
Author(s):  
Yasunori Yoshimura ◽  
Toshio Kasai ◽  
Hiroshi Ohoyama ◽  
Keiji Kuwata
Keyword(s):  
Internal Energy ◽  
Rotational Temperature ◽  
Similar Data ◽  
Vibrational States ◽  
Energy Distributions ◽  
Vibrationally Excited ◽  
Elementary Reactions ◽  
Electronically Excited ◽  
Vibrational Bands ◽  
Rotational Distribution

Chemiluminescence of the vibrationally excited HF† and of the electronically excited HSO* in the 2A′ state were observed in the elementary reactions of F + H2S and HS + O3. In the F + H2S reaction, the vibrational populations of HF† in ν = 3 and 4 were found to be nonstatistical but the rotational distribution in the ν = 4 state was found to be Boltzmann-like with a rotational temperature of 700 K, confirming similar data obtained by different methods. The HSO* emission was observed in the HS + O3 elementary reaction. The spectrum of HSO* characterized by broad vibrational bands indicates nonstatistical excitation for the rotational and vibrational states. Keywords: chemiluminescence, internal energy distribution, F + H2S, HS + O3, HF†, HSO*.

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

1956 ◽  
Vol 233 (1195) ◽  
pp. 455-464 ◽  
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.

Persistent Photoconductivity And Thermal Recovery Kinetics Of Low Energy Ar + Bombarded GaAs

1991 ◽  
Vol 223 ◽  
Author(s):  
A. Vaseashta ◽  
L. C. Burton
Keyword(s):  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Thermal Recovery ◽  
Low Energy ◽  
Persistent Photoconductivity ◽  
Transport Parameters ◽  
Excellent Correlation ◽  
Proposed Model ◽  
Transient Spectroscopy ◽  
Kinetics Of

ABSTRACTKinetics of persistent photoconductivity, photoquenching, and thermal and optical recovery observed in low energy Ar+ bombarded on (100) GaAs surfaces have been investigated. Rate and transport equations for these processes were derived and simulated employing transport parameters, trap locations and densities determined by deep level transient spectroscopy. Excellent correlation was obtained between the results of preliminary simulation and the experimentally observed values. The exponential decay of persistent photoconductivity response curve was determined to be due to metastable electron traps with longer lifetime and is consistent with an earlier proposed model.

Convergence Properties of Quasiclassical Trajectory Calculations on Dynamics of Autoionization Event in He(23S)-D2 Penning Ionization

1997 ◽  
Vol 62 (2) ◽  
pp. 154-171 ◽  
Author(s):  
Jan Vojtík ◽  
Richard Kotal
Keyword(s):  
Branching Ratios ◽  
Classical Trajectory ◽  
Vibrational States ◽  
Penning Ionization ◽  
Trajectory Calculations ◽  
Quantum Mechanical Treatment ◽  
Total Ionization ◽  
Vibrational Levels ◽  
Degree Of Convergence ◽  
Product Branching

An analysis of the degree of convergence of theoretical pictures of the dynamics of the autoionization event He(23S)-D2(v" = 0) -> [He...D2+(v')] + e is presented for a number of batches of Monte Carlo calculations differing in the number of the trajectories run. The treatment of the dynamics consists in 2D classical trajectory calculations based on static characteristics which include a quantum mechanical treatment of the perturbed D2(v" = 0) and D2+(v') vibrational motion. The vibrational populations are dynamical averages over the local widths of the He(23S)-D2(v" = 0) state with respect to autoionization to D2+(...He) in its v'th vibrational level and the Penning electron energies are related to the local differences between the energies of the corresponding perturbed D2(v" = 0)(...He*) and D2+(v')(...He) vibrational states. Special attention is paid to the connection between the requirements on the degree of convergence of the classical trajectory picture of the event and the purpose of the calculations. Information is obtained regarding a scale of the trajectory calculations required for physically sensible applications of the model to an interpretation of different type of experiments on the system: total ionization cross section measurements, Penning ionization electron spectra, subsequent 3D classical trajectory calculations of branching ratios of the products of the postionization collision process, and interpretation of electron ion coincidence measurements of the product branching ratios for individual vibrational levels of the nascent Penning ion.

Energies and Electric Dipole Moments of the Bound Vibrational States of HN2+ and DN2+

2008 ◽  
Vol 73 (6-7) ◽  
pp. 873-897 ◽  
Author(s):  
Vladimír Špirko ◽  
Ota Bludský ◽  
Wolfgang P. Kraemer
Keyword(s):  
Dipole Moment ◽  
Nearest Neighbor ◽  
Energy Surface ◽  
Dipole Moments ◽  
Three Dimensional ◽  
Vibrational States ◽  
Spacing Distribution ◽  
Triatomic Molecules ◽  
Vibrational Levels ◽  
Different Levels

The adiabatic three-dimensional potential energy surface and the corresponding dipole moment surface describing the ground electronic state of HN2+ (Χ1Σ+) are calculated at different levels of ab initio theory. The calculations cover the entire bound part of the potential up to its lowest dissociation channel including the isomerization barrier. Energies of all bound vibrational and low-lying ro-vibrational levels are determined in a fully variational procedure using the Suttcliffe-Tennyson Hamiltonian for triatomic molecules. They are in close agreement with the available experimental numbers. From the dipole moment function effective dipoles and transition moments are obtained for all the calculated vibrational and ro-vibrational states. Statistical tools such as the density of states or the nearest-neighbor level spacing distribution (NNSD) are applied to describe and analyse general patterns and characteristics of the energy and dipole results calculated for the massively large number of states of the strongly bound HN2+ ion and its deuterated isotopomer.

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