A Density Functional Theory Calculations-Based Approach that Predicts Layered Materials with Emergent Structures

TL;DR

This paper introduces a density functional theory-based method that predicts layered materials with complex, emergent structures and turbostratic disorder, expanding the ability to discover novel magnetic layered compounds.

Contribution

It presents a novel approximation approach enabling the prediction of new layered materials with emergent structures and turbostratic disorder using DFT calculations.

Findings

Successfully identified the SnSe₂-VSe₂ system.

Predicted stable Fe₃Ge-VSe₂ structure.

Discovered multiple stable MnₓSe_y-VSe₂ layered structures.

Abstract

Recent work shows that density functional theory calculations accurately describe materials exhibiting turbostratic disorder between layers of incommensurate constituents. These calculations approximate one of the constituents as a finite island between continuous layers of the other constituent. This island approximation allows equal treatment of all relative angles between the interleaved layers, and it removes the requirement of a unit cell that is commensurate with both layers. The work presented here uses this approximation to search for new layered materials that exhibit turbostratic disorder and magnetic structure. In a first application, the approach finds the recently synthesized SnSe$_2$-VSe$_2$ system. The approach predicts a stable Fe$_3$Ge-VSe$_2$ structure and multiple stable structures that interleave Mn$_x$Se$_y$ layers with VSe$_2$ layers. These Mn$_x$Se$_y$ layers exhibit emergent structures and stability.