Structure and Stability of Metallic Hydrogen

Abstract
A calculation of the electronic energy and optimum atomic spacing for an equally spaced linear array of hydrogen atoms is combined with other information to yield an improved analysis of the existence and stability of metallic hydrogen. A filamentary structure postulated by others is predicted not to be stable or metastable at any pressure; previous predictions of a transition under pressure to a metallic cubic (or hcp) phase are reaffirmed. The energies and interatom spacings in H2, linear chains, and cubic crystals are in good accord with chemical expectations.