Recombination of ground-state halogen atoms. Part 1.—Radiative recombination of chlorine atoms

1968 ◽  
Vol 64 (0) ◽  
pp. 1816-1835 ◽  
Author(s):  
M. A. A. Clyne ◽  
D. H. Stedman
Keyword(s):  
Ground State ◽  
Radiative Recombination ◽  
Chlorine Atoms ◽  
Halogen Atoms

scholarly journals Photoionisation Cross Sections of Chlorine Atoms and Molecules at 584 Å

1986 ◽  
Vol 39 (5) ◽  
pp. 779 ◽  
Author(s):  
WJ van der Meer ◽  
RJ Butselaar ◽  
CA de Lange
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Ground State ◽  
Modulation Method ◽  
Absolute Cross Section ◽  
Molecular Chlorine ◽  
Chlorine Atoms ◽  
Atoms And Molecules ◽  
Ionic States ◽  
State Ionic

A recently developed modulation method is used to obtain cross sections for the photoionisation of ground state neutral to ground state ionic, atomic and molecular chlorine relative to that of the HCl + (X2n 1IZ,3IZ) +-- HCl(XI ~ +) transition at the He Ia wavelength. With the known absolute cross section of the latter process, determined by (e,2e) coincidence spectroscopy, the present ell,periments provide absolute photoionisation cross sections of the CI + epz,l,o) +-- Clep) and Cli (XZ n g, 1IZ,3 IZ) +-- Clz (X I ~ t) transitions. Relative cross sections, previously determined for the transitions to the additional Cl and Clz ionic states accessible with He Ia radiation, are used to obtain absolute cross sections for the Cl+(IDz, ISO) +-- Clep) and Cli(AZnu,1IZ,3IZ, BZ~t) +-- Clz(XI~t) ionisation processes.

Photoluminescence Study of Radiative Recombination in Porous Silicon

1993 ◽  
Vol 298 ◽  
Author(s):  
Chun Wang ◽  
Franco Gaspari ◽  
Stefan Zukotynski
Keyword(s):  
Porous Silicon ◽  
Excited States ◽  
Ground State ◽  
Radiative Recombination ◽  
Single Electron ◽  
Photoluminescence Study ◽  
Recombination Centre ◽  
Electron Center ◽  
Recombination Centers

AbstractPhotoluminescence has been studied in porous silicon. Two types of radiative recombination centers have been identified. One gives rise to luminescence at about 820 nm and is believed to be related to Si-H bonds. The second gives rise to luminescence at about 770 nm and is likely associated with S-O bonds. Above about 20K radiative recombination is assisted by excited states of the recombination centre located about 10 meV above the ground state. The Si-H recombination centre is a single electron center whereas the Si-O center appears to be a multi-electron center.

Non L.T.E. Properties of Quasistationary Oxygen Plasmas

1976 ◽  
Vol 31 (3-4) ◽  
pp. 362-368 ◽  
Author(s):  
M. Cacciatore ◽  
M. Capitelli
Keyword(s):  
Excited States ◽  
Cross Sections ◽  
Ground State ◽  
Radiative Recombination ◽  
Local Thermodynamic Equilibrium ◽  
Collisional Radiative Model ◽  
Radiative Model ◽  
Ionization Coefficients ◽  
Selection Of ◽  
The Continuum

The non L.T.E. (local thermodynamic equilibrium) properties of optically thin and thick quasistationary oxygen plasmas have been calculated for the temperature range k T = 0.5 - 1.5 eV and for the electron density interval 108 - 1016 cm-3 , by using the collisional-radiative model of Bates, Kingston and McWhirther. The results include1 the coefficients r0(i) and r1(i), which represent the contribution to the population density of the ith quantum level from the continuum and from the ground state, respectively2 the values of α and S, which are the collisional-radiative recombination and ionization coefficients, respectively. The accuracy of the present results is discussed in connection with the adopted plasma model and with the selection of the collisional cross sections for forbidden and allowed transitions. A discussion is also presented of the influence of the two low lying excited states of oxygen atoms (i.e. the states 2p41D, 2p41S) on the non L.T.E. properties of these plasmas. A satisfactory agreement is found with the calculations of Julienne et al. and with the experimental results of Jones.

HALOGEN SENSITIZED PHOTOREACTIONS

1948 ◽  
Vol 26b (9) ◽  
pp. 629-642
Author(s):  
J. W. T. Spinks
Keyword(s):  
Experimental Evidence ◽  
Wave Length ◽  
Intermediate Compound ◽  
Oxidation Reactions ◽  
Chain Reaction ◽  
Chlorine Atoms ◽  
Spectroscopic Evidence ◽  
Chemical Mechanisms ◽  
Halogen Atoms ◽  
A Chain

Spectroscopic evidence indicates that reactions photosensitized by fluorine would take place by way of fluorine atoms. Similarly, the sensitizing action of chlorine will practically always be due to chlorine atoms. For bromine, when the wave length is less than 5107 Å, reaction will be by way of bromine atoms. Experiments using wave lengths 5107–6290 Å also probably involve bromine atoms although the possibility of reaction due to excited bromine molecules cannot be wholly ruled out. Iodine atoms are produced in photosensitization experiments involving iodine and wave lengths less than 4989 Å. Experimental evidence also favors the production of iodine atoms using wave lengths up to 6200 Å. Mechanisms in accordance with the above are advanced for a number of chlorine sensitized oxidation reactions. In the oxidation reactions an intermediate compound with a trivalent carbon is formed which reacts with oxygen forming a peroxide, giving rise to a chain reaction. Reactions sensitized by bromine and iodine are also discussed. It appears that all the halogen sensitized gaseous photoreactions thus far known can be explained by chemical mechanisms involving halogen atoms.

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