Phase-Space Approach to the Density-Functional Calculation of Compton Profiles of Atoms and Molecules

The phase-space distribution function corresponding to a ground-state density of a many-electron system proposed earlier is explored as a means for generation of momentum-space properties through density-functional theory. Excellent results are found for the spherically averaged Compton profiles for several atoms and the molecules H₂ and N₂, as well as the directional Compton profiles for N₂, thereby providing both a useful scheme for computation of such profiles and confirmation of the basic theory. The entropy-maximization procedure employed is discussed from the point of view of information theory.