ABSTRACT
The presentation of scattering cross sections is continued in this chapter, with specific reference to selected diatomic gases. The gases onsidered are carbon monoxide (CO), hydrogen (H2), nitrogen (N2), oxygen (O2), and nitrous oxide (NO). The molecular structure of these gases is relatively simple and, except for CO and NO, they are all nonpolar. The long-range dipole interaction between the electron and the molecule in polar gases presents difficulties for complete theoretical understanding1 and experimental methods are the main source, unlike in rare gases (Chapter 3) where theory can supplement measurements. A brief presentation of interaction potentials is given in Chapter 1 and Johnson2 may be referred to for further details. For details of polarization refer to McDaniel3 and Raju4. The classical theory for elastic scattering, which is only of academic interest, may be found in Yang and Ree5 according to which the differential scattering cross section in the CM system is given by the expression
QdiffðYÞ ¼ v4=n0 ð4:1Þ
where v0 is the initial relative velocity of approach, Y is the angle of scattering (Figure 1.18) and n a constant.
