Accession Number:

ADA030889

Title:

Chemical Reactivity and Molecular Beam Scattering

Descriptive Note:

Final rept. 1 Feb 1972-31 Mar 1976

Corporate Author:

YALE UNIV NEW HAVEN CT DEPT OF ENGINEERING AND APPLIED SCIENCE

Report Date:

1976-07-31

Pagination or Media Count:

42.0

Abstract:

The research program detailed in this final report concerns the measurement of integral cross sections for a large number of molecules. From such cross sections it is possible to determine the so-called van der Waals or C6 coefficients for the attractive portion of the pair-wise potentials, which follow a 1r raised to 6th power dependence on the inter-particle distance. The authors obtained absolute values for total scattering cross sections at velocities well-defined for each of 38 different systems involving Ar and a variety of target molecules, chiefly hydrocarbons. From these scattering cross sections C6 values for each system were deduced. Using the values of these coefficients obtained from our cross section measurements, they were also able to test a mixing rule recommended by Kramer and Herschbach which allows estimation of force constants between unlike molecules from their interaction with a common partner. They have evaluated the method as a predictive tool for the estimation of transport and thermodynamic properties which depend upon the attractive forces between molecules.

Subject Categories:

  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE