A. A. Ivanov
Indicator of efficiency of experiment in
the gas electron diffraction (GED)
Abstract
The ineffectiveness of the traditional
probe electron diffraction experiment on free molecules (atoms) has been shown,
which prevents the development of the diffraction structural method in gas
phase electron diffraction. Molecular beam application allowed to determine the
quantitative performance indicator of the scattering process on the given
experimental equipment. The quantitative value of effective cross-section on
residual gas molecules σext(SmaxÅ–1) has been suggested as a
technical characteristic for the electron diffraction equipment complex. A
nomographic chart for determining the number of molecules of any substance has
been drawn up, in order to obtain a given density of scattered charge on the
detector within the maximum sector radius. The author refers to the
GED-community of the need to agree on a single estimate of the efficiency of
electron scattering experiment at the free molecules.
Key words: gas phase electron diffraction,
efficiency of process, molecular beam, scattering cross-section.
Copyright (C) Chemistry Dept., Moscow State University, 2002
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