STUDY OF COMPTON PROFILES IN ATOMIC AND MOLECULAR SYSTEMS

Abstract

The work reported in the thesis contains the results of the theOretical study of the Compton profile and other related properties for the atomic and the molecular systems. The thesis has been divided into seven chapters, the first of which gives a brief review of the earlier works and the general theory regarding the impulse approximation for the Compton profile. In Chapter 2 the analytic expressions are obtained for the isotropic Compton profiles (ICP) using a linear combination of a small number of the Gaussian-type orbitals (GTO's) for each Slater--type orbital (STO). The technique has been applied to evaluate ICP's of the atomic sodium and aluminium, and the inert gas atoms (He,Ne0Ar,Kr). The results of the present calculation compare well with the experimental data and also with the theoretical calculations performed by using the same Hartree-Fock wave functions. The next section of this chapter deals with the comparison of ICP's and momentum expectation values obtained from the STO's, a six term Gaussian expansion of each STO, and the GTO's for the atomic krypton. The last section of this chapter contains the calculations of the incoherent scattering factors,, which have been performed by direct integration over the ICP, for the atomic sodium, aluminium, argon and krypton. The ana-lytical expression obtained for the ICP has been. employed for this investigation. The results have been compared with those obtained by the Waller-Hartree (WH) theory. It is found that at low scattering angles, the ICP results differ significantly from the WH scattering factors...