Emergence of quasi-one-dimensional physics in Mo$_3$S$_7$(dmit)$_3$, a nearly-isotropic three-dimensional molecular crystal

TL;DR

This study uses density functional theory to reveal that Mo$_3$S$_7$(dmit)$_3$ exhibits emergent quasi-one-dimensional physics due to its layered structure and unique electronic states, despite being nearly isotropic in three dimensions.

Contribution

The paper introduces an ab initio tight-binding model showing how layered Mo$_3$S$_7$(dmit)$_3$ supports quasi-1D bands and localized states, bridging 3D structure with 1D physics.

Findings

Supports states localized to dodecahedral rings within the plane.

Supports quasi-1D spin-one model on a layered honeycomb lattice.

Presence of Dirac cones crossing the Fermi energy.

Abstract

We report density functional theory calculations for Mo$_3$S$_7$(dmit)$_3$. We derive an ab initio tight-binding model from overlaps of Wannier orbitals; finding a layered model with interlayer hopping terms $\sim3/4$ the size of the in-plane terms. The in-plane Hamiltonian interpolates the kagom\'e and honeycomb lattices. It supports states localized to dodecahedral rings within the plane, which populate one-dimensional (1D) bands and lead to a quasi-1D spin-one model on a layered honeycomb lattice once interactions are included. Two lines of Dirac cones also cross the Fermi energy.