Prediction of new crystal structure phases in metal borides: a lithium monoboride analog to MgB2

TL;DR

This paper uses ab initio data mining to discover new layered lithium monoboride phases in metal borides, which are marginally stable at ambient conditions but could be good superconductors under pressure.

Contribution

It identifies previously unknown layered lithium monoboride phases with potential superconducting properties using ab initio data mining and calculations.

Findings

New layered lithium monoboride phases are marginally stable at ambient conditions.

These phases become more stable than known compounds under moderate pressure.

The electronic features suggest potential as good superconductors.

Abstract

Modern compound prediction methods can efficiently screen large numbers of crystal structure phases and direct the experimental search for new materials. One of the most challenging problems in alloy theory is the identification of stable phases with a never seen prototype; such predictions do not always follow rational strategies. While performing ab initioa data mining of intermetallic compounds we made an unexpected discovery: even in such a well-studied class of systems as metal borides there are previously unknown layered phases comparable in energy to the existing ones. With ab initio calculations we show that the new metal-sandwich (MS) lithium monoboride phases are marginally stable under ambient conditions but become favored over the known stoichiometric compounds under moderate pressures. The MS lithium monoboride exhibits electronic features similar to those in magnesium diboride and is expected to be a good superconductor.