Ab initio two-body potentials and the properties of condensed phases of helium atoms

A careful comparison of some properties of systems of helium atoms in the liquid and solid phases is performed for several ab initio two-body potentials from the literature. Additional contributions from a three-body potential are considered as well. The multiweight diffusion Monte Carlo method is employed to quantitatively compute the small changes in the properties of the system as the different potentials are considered.

Figure 1

Plot of the $V_{\mathrm{pr}}$ (solid line) and $V_{\mathrm{HF}}$ (point dashed line) two-body potentials versus the separation distance. At the graph scale the $V_p$ and $V_{\mathrm{pr}}$ potentials cannot be distinguished.

Figure 2

Equations of state for the liquid phase obtained using the $V_{p3}$ (dashed line), $V_{\mathrm{pr}3}$ (solid line), and $V_{\mathrm{HF}3}$ (short dashed line) potentials. The circles represents data from Ref. 32. The dashed-dotted line stand for results from Ref. 12 obtained using only the two-body potential $V_{\mathrm{HF}}$ of Eq. (2.2).

Figure 3

Equations of state for the solid phase determined using the $V_{p3}$ (dashed line), $V_{\mathrm{pr}3}$ (solid line), and $V_{\mathrm{HF}3}$ (short dashed line) potentials. The circles represents data from Ref. 33. The dashed-dotted line stand for results from Ref. 12 obtained using only the two-body potential $V_{\mathrm{HF}}$ of Eq. (2.2).