Pseudo pair potential between protons in dense hydrogen from first principles

Abstract

Calculating the underlying quantum behaviour of dense hydrogen has proven to be difficult due to subtle electronic effects and also the lightness of the proton leading to large quantum motion. The analytical form of the contribution from the nuclear and electronic degrees of freedom (DOF) is integrated out of the Schödinger equation by way of the generated pseudo pair potential in this paper. This is accomplished through the adiabatically linear response approximation of an electron gas-jellium model to the perturbations induced by discrete hydrogen ions in the absence of an external field. This pair potential for the hydrogen ions can then be fitted to generate first-principles data. From these pair potentials, computational time can be drastically reduced for larger systems of dense hydrogen to determine their various properties.

GRAPHICAL ABSTRACT

Keywords:

• Pair potential
• dense metallic hydrogen
• nuclear quantum effects
• electronic screening
• MD calculations

Acknowledgments

The authors thank members of the McMahon Research Group, for help with the hydrogen phase diagram.

Data availability statement

The data that support the findings of this study are available from the corresponding author, R. S. R., upon reasonable request.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

J. M. M. acknowledges startup support from the U.S. Department of Energy (DOE Project Award #DE-EE0008429), Washington State University and the Department of Physics and Astronomy thereat .