scholarly journals OPTICAL PUMPING OF COPPER METASTABLE ATOMS USED FOR LIFETIME MEASUREMENTS OF HIGH VIBRATIONAL LEVELS OF ELECTRONICALLY EXCITED COPPER HALIDES FORMED BY REACTIVE COLLISIONS

1991 ◽  
Vol 01 (C7) ◽  
pp. C7-493-C7-496
Author(s):  
P. KOWALCZYK ◽  
I. HIKMET ◽  
N. SADEGHI
1971 ◽  
Vol 26 (10) ◽  
pp. 1617-1625 ◽  
Author(s):  
F. Linder ◽  
H. Schmidt

Abstract Elastic scattering, vibrational excitation to v=1, 2, 3, 4 of the electronic ground state, and electronic excitation to the states a1Δ g and b1Σg+ of O2 have been measured in a crossed beam apparatus for collision energies from nearly 0 eV to 4 eV. Differential and integral cross sections have been determined and calibrated on an absolute scale. From 15 vibrational levels of O2-, which could be observed as resonances in the cross sections, the spectroscopic constants for the vibrational structure of O2- have been derived: ωe = 135 meV and ωeχe = 1 meV. The cross sections for vibrational excitation have the order of 10-18 cm2. eV for the larger resonance peaks. Detailed cross sections have been listed in Table 1. The half width of the resonance can be estimated to Γ ≈ 0.5 meV, which corresponds to a lifetime tof 10-12 sec for the O2- states. The angular dependence of pure resonance scattering is rather flat and not in accordance with the simplest theoretical model. An analysis of the angular dependence and of the rotational structure of the resonance in a somewhat extended model have been performed. - No electronically excited O2-states could be detected in the energy range up to 3 eV.


1960 ◽  
Vol 38 (10) ◽  
pp. 1648-1651 ◽  
Author(s):  
Paul Harteck ◽  
Robert R. Reeves ◽  
Gene Mannella

Various metal surfaces such as nickel, cobalt, copper, and silver give rise to a reddish luminosity in a stream of N- and O-atoms. Spectroscopic and photographic analysis of these glows indicate the formation of electronically excited molecules on the metal surface which diffuse into the gas phase and radiate. Two parallel processes are involved: the formation of an NO(B2Π), which results in NO β radiation, and the formation of an [Formula: see text] which, in collision, crosses into the N2(B3Π0) state and then radiates back to the [Formula: see text] giving the N2 first positive system. The N2 first positive system observed here shows the strongest bands from v' = 8 and 6; these vibrational levels straddle the [Formula: see text] potential energy curve crossing point. This crossing-over of N2 molecules into the (B3Π0) at this point may explain the observed strong v' = 6 transition in normal N-atom recombination if it is assumed that some of the N-atoms recombine into the [Formula: see text] in addition to the [Formula: see text]state.The N2 second positive system (C3Πu → B3Π0) has also been observed over copper in an N- and O-atom stream. This is most surprising since the N2(C3Πu) has about 1.4 ev more than [Formula: see text]


2006 ◽  
Vol 24 (11) ◽  
pp. 2823-2839 ◽  
Author(s):  
V. A. Yankovsky ◽  
R. O. Manuilova

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


1971 ◽  
Vol 49 (8) ◽  
pp. 1268-1271 ◽  
Author(s):  
G. I. Mackay ◽  
R. E. March

Electron beam excitation of nitrogen was utilized to produce ions in the zeroth and first vibrational levels of the B2Σu+ state. The rate constants for the collisional deactivation of electronically excited N2+, for each of N2 and NO, were determined individually for the v′ = 0 and v′ = 1 vibrational levels of the N2+(B2Σu+) state. Charge transfer is the most probable mode of deactivation.


1972 ◽  
Vol 50 (1) ◽  
pp. 1-7 ◽  
Author(s):  
G. I. Mackay ◽  
R. E. March

Total deactivation rate constants have been determined for N2+(B2Σu+) and the (A2Πu) and (B2Σu+) states of CO2+ with a number of quenchers. The energy specific total deactivation rate constant is compared to the total radiative lifetime of the excited species. A particular novelty of the technique is that it does not require a complete knowledge of the formation modes for the excited species. The results are compared with theoretical values obtained from the ion-induced dipole model. Individual deactivation rate constants are presented for N2+(B2Σu+) ions in the v = 0, 1, and 2 vibrational levels quenched by N2, O2, H2, and CO2; and for the(A2Πu) and (B2Σu+) states of CO2+ quenched byCO2, N2, O2, NO, and H2. Charge transfer is the most probable mode of deactivation except in the CO2+–H2 reactions where H-atom abstraction is more probable.


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