Momentum density and Compton profile ofTiCl4

The ground-state momentum density $\rho \left(\overrightarrow{\mathrm{p}}\right)$ and Compton profile $S(\overrightarrow{\mathrm{k}},\omega )$ of ${\mathrm{TiCl}}_4$ have been calculated. Molecular-orbital (MO) wave functions were obtained in the Hartree-Fock-Slatter (HFS) model by use of the discrete variational method. Results for MO wave functions are compared with atomic superposition models based on Hartree-Fock and HFS atomic eigenfunctions. Shifts in spherical average momentum density and Compton profile owing to chemical bonding are examined; the symmetry and magnitude of the anisotropy is studied. Following the spherical-harmonic analysis of Mijnarends, we discuss practical methods for obtaining ($\mathrm{lm}$) components of $S$; simple expressions for certain moments of the anisotropic density are given.