Showing papers by "Sydney Leach published in 1980"
TL;DR: In this article, the authors apply recent theories of radiationless transitions to the case of photon emission from molecular ions, and derive values for average coupling energies, densities of states, and level widths.
Abstract: We apply recent theories of radiationless transitions to the case of photon emission from molecular ions. Mono‐ and dichloroacetylene cations are formed in excited electronic states by 21.22 eV (He i) or 16.85 eV (Ne i) photon excitation of the parent molecules. Multiexponential decay is observed for emission from the ? 2Π(g) state of each ion as previously reported for 30 V electron impact excitation. Emission quantum yields are determined in the photon excitation experiments. Coupling between the ? 2Π(g) state and high vibrational levels of the ? 2Π(u) ground state is invoked to explain the data presented. The ’’strong‐coupling’’ theory of ’’intermediate’’ case radiationless transitions is used to infer values for average coupling energies, densities of states, and level widths. We conclude by treating several possible explanations for the fate of ’’hot’’ ground‐electronic‐state ions: (i) intramolecular vibrational relaxation; (ii) collisional quenching; and (iii) infrared emission.
24 citations
01 Jan 1980
TL;DR: A general review of present and future applications of synchrotron radiation to the study of molecular dynamics and photochemistry can be found in this paper, where the authors discuss the following: 1) Intramolecular and intermolecular relaxation processes in gas and condensed phases; 2) Time and energy resolved observables regarding molecular relaxation; Coherent optical effects; 3) Relevant excitation energy regions for the study on molecular dynamics; 4) Excitation sources; Comparison between synchroron, laser and plasma sources; 5) Some experimental systems and modern detection methods
Abstract: A general review is given of present and future applications of synchrotron radiation to the study of molecular dynamics and photochemistry. The following are discussed : 1) Intramolecular and intermolecular relaxation processes in gas and condensed phases ; 2) Time and energy resolved observables regarding molecular relaxation ; Coherent optical effects ; 3) Relevant excitation energy regions for the study of different aspects of molecular dynamics ; 4) Excitation sources ; Comparison between synchrotron, laser and plasma sources ; 5) Some experimental systems and modern detection methods ; 6) Further applications of high energy molecular dynamics ; 7) Special constraints and benefits of working with synchrotron radiation.
21 citations
TL;DR: In this paper, the direction of the first doublet-doublet transition moment was determined, consistent with the symmetry assignment 2 A 2 for the first excited state of duryl when this radical is considered, to a first approximation and from the electronic viewpoint, as belonging to the C 2v point group.
3 citations