Predicted Superconductive Properties of Lithium under Pressure

Abstract

A superconducting state of lithium has not been found at ambient pressure, but the present theoretical work shows that high values of the critical temperature, T(c), may be expected for some high-pressure phases. Ab initio electronic structure calculations are used to calculate the electron-phonon coupling in a "rigid-muffin-tin approximation," and estimates using McMillan's formula suggest that under increasing pressure T(c) in fcc-Li may reach 50--70 K before transitions occur to the rhombohedral (hR1-Li) and subsequently to the cI16-Li phase near 40 GPa. In cI16-Li T(c) may reach a maximum in the range 60--80 K.

Positron confinement in embedded lithium nanoclusters

“…The fcc phase for bulk Li is otherwise only observed at low temperatures and high pressures. 18,19 A similar effect was reported in the work mentioned above 12 where the crystal structure of Cu nanoclusters embedded in Fe is expected, on the basis of lattice parameter similarity, to be bcc rather than fcc.…”

Assembling the puzzle of superconducting elements: a review

“…Calculations predicted superconductivity of Li at high pressure [25] with a T c of up to 80 K [26]. Early measurements of Li resistivity under pressure revealed a phase transition accompanied by a sudden drop of resistivity around 7 K, attributed to possible superconductivity [27].…”

Symmetry breaking and restoring under high pressure: the amazing behaviour of the "simple" alkali metals

“…Such classification applies to the cI16 structure as well, after distortion from the parent bcc lattice, but now with a basis of four atoms for each sublattice. The cI16 phase by itself is not dimerized, and it has been recently predicted to be even superconducting [28,29]. We would like to test its stability with respect to a dimerized phase obtained by rigidly shifting the two sublattices each other of a tiny amount y along the (111) direction.…”