A tight-binding model of an ambient-pressure molecular Dirac electron system

Abstract

By deriving a tight-binding model, we demonstrate a mechanism of forming a nodal line of Dirac points in a single-component molecular conductor [Pt(dmtd)${}_2$] [Zhou {\it et al.}, Chem. Commun. {\bfseries 55}, 3327 (2019)], consisting of HOMO and LUMO. The nodal line is obtained as the intersection of two surfaces, where one corresponds to the HOMO-LUMO band crossing and another is vanishing of the HOMO-LUMO couplings due to their different symmetries. The latter property is essential for the Dirac electron in molecular conductors. The nature of the open nodal line is discussed in terms of the parity of the wavefunctions at eight TRIMs (time reversal invariant momenta).

arXiv comment12 pages, 7 figures

References in corpus (5)

• Two-Dimensional Gas of Massless Dirac Fermions in Graphene
• Topological Insulators with Inversion Symmetry
• Pressure-Induced Zero-Gap Semiconducting State in Organic Conductor $\alpha$-(BEDT-TTF)${}_2$I${}_3$ Salt
• Topological semimetals studied by ab initio calculations
• Effective Hamiltonian of Topological Nodal Line Semimetal in Single-Component Molecular Conductor [Pd(dddt)${}_2$] from First-Principles

Cited by in corpus (5)

• Electronic Structure of a Single-Component Molecular Conductor [Pd(dddt)${}_2$] (dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiolate) under High Pressure
• Tight-Binding Model and Electronic Property of Dirac Nodal Line in Single-Component Molecular Conductor [Pt(dmdt)${}_2$]
• Anomalous conductivity of two-dimensional Dirac electrons in organic conductor under pressures
• Nodal-line semimetal HMTSF-TCNQ: Anomalous orbital diamagnetism and charge density wave
• Fragment-orbital-dependent spin fluctuations in the single-component molecular conductor [Ni(dmdt)${}_2$]