Prospects for Superconductivity in LiBSi

TL;DR

This paper predicts that LiBSi, a modified lithium borocarbide, should be a superconductor with a transition temperature similar to MgB2, based on symmetry and electronic considerations.

Contribution

It introduces a new candidate superconductor, LiBSi, by replacing C with Si in LiBC, guided by symmetry principles and electronic structure analysis.

Findings

LiBC is non-superconducting.

Replacing C with Si in LiBC achieves symmetry with MgB2.

LiBSi is predicted to be a superconductor with Tc similar to MgB2.

Abstract

The search for superconductivity in materials iso-structural and iso-electronic with magnesium diboride, MgB2, has not yielded results with Tc near 39K. In particular, Lithium borocarbide, LiBC, and its modification Li0.5BC, proved to be non-superconducting. Using our materials-specific condition for superconductivity and the symmetry principles for superconductor search, we show that LiBC cannot be a superconductor. By replacing C in LiBC with Si we achieve valence electron count (Ne) and atomic number (Z) symmetry with MgB2. We therefore predict that Lithium boron silicon, LiBSi, should be a superconductor with Tc comparable to MgB2.