No abstract

The Li-Sn binary system has been the focus of extensive research because it features Li-rich alloys with potential applications as battery anodes. Our present re-examination of the binary system with a combination of machine learning and ab initio methods has allowed us to screen a vast configuration space and uncover a number of overlooked thermodynamically stable alloys. At ambient pressure, our evolutionary searches identified an additional stable Li3Sn phase with a large BCC-based hR48 structure and a possible high-T LiSn4 ground state. By building a simple model for the observed and predicted Li-Sn BCC alloys we constructed an even larger viable hR75 structure at an exotic 19:6 stoichiometry. At 20 GPa, low-symmetry 11:2, 5:1, and 9:2 phases found with our global searches destabilize previously proposed phases with high Li content. The findings showcase the appreciable promise machine-learning interatomic potentials hold for accelerating ab initio prediction of complex materials.

Reported Li–B–C compounds and calculated phase diagram establishing conditions required for LiBC delithiation.

Topological metals are a new class of materials that feature Fermionic quasiparticles with the presence of non-trivial band crossings near the Fermi level. In this work, we focus on establishing crystal structure ground states and the corresponding topological properties of MnRhP. Under ambient pressure and low temperatures, we find that an orthorhombic oP12 polymorph is favored over the known hexagonal hP9 phase. Pressures above 15 GPa stabilize tetragonal (tP6′), hexagonal (hP9′), and orthorhombic (oP12′) phases with inverted population of metal sites. While oP12′ has the lowest enthalpy, we show that hP9′ is more consistent with the previous X-ray diffraction data collected at 60 GPa. Our analysis of hP9 and oP12 topological properties reveals the existence of nodal lines around the Γ-point that are gapped out when spin–orbit coupling effects are included and transform into Weyl nodes with opposite chirality near the Fermi level. The calculated large values of the anomalous Hall conductivity in hP9, oP12, and tP6′ and the Z 2 topological invariant in the non-magnetic hP9′ can be used to verify the predicted non-trivial robust topological features of MnRhP under ambient and high pressures.