Microscopic calculations for normal and polarized liquidHe3

Accurate variational calculations are carried out for the ground-state quantities of the normal and fully spin-polarized phases of liquid ${}_{}{}^3{}_{}{}^{}\mathrm{He}$. The variational wave functions include semioptimized two-body, three-body, and backflow correlations. Expectation values are calculated using Fermihypernetted-chain summation techniques. The elementary diagrams are summed with the scaling approximation developed earlier for Bose liquids. Results of calculations using the interatomic potential of Aziz et al. from equilibrium to melting density are reported. The calculated equation of state, sound velocity, and liquid structure function for the normal phase are in close agreement with the experimental data. The three-body and backflow correlations are found to be important in achieving this agreement with experiment. The energy of the spin-polarized phase is found to be above that of the normal phase over the entire liquid density range, and it is found that the backflow correlations are necessary to achieve this result.