Unconventional Materials: the mismatch between electronic charge centers and atomic positions

Abstract

The complete band representations (BRs) have been constructed in the work of topological quantum chemistry. Each BR is expressed by either a localized orbital at a Wyckoff site in real space, or by a set of irreducible representations in momentum space. In this work, we define unconventional materials with a common feature of the mismatch between average electronic centers and atomic positions. They can be effectively diagnosed as whose occupied bands can be expressed as a sum of elementary BRs (eBRs), but not a sum of atomic-orbital-induced BRs (aBRs). The existence of an essential BR at an empty site is described by nonzero real-space invariants (RSIs). The "valence" states can be derived by the aBR decomposition, and unconventional materials are supposed to have an uncompensated total "valence" state. The high-throughput screening for unconventional materials has been performed through the first-principles calculations. We have discovered 423 unconventional compounds, including thermoelectronic materials, higher-order topological insulators, electrides, hydrogen storage materials, hydrogen evolution reaction electrocatalysts, electrodes, and superconductors. The diversity of these interesting properties and applications would be widely studied in the future.

arXiv comment10+354 pages, 11 figures

References in corpus (33)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Topological Insulators
• Topological insulators and superconductors
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
• Topological Crystalline Insulators
• Topological Materials: Weyl Semimetals
• Topological quantum chemistry
• Topological Crystalline Insulators in the SnTe Material Class
• The (High Quality) Topological Materials In The World
• Transparent dense sodium
• Symmetry-based Indicators of Band Topology in the 230 Space Groups
• Quantization of fractional corner charge in $C_n$-symmetric higher-order topological crystalline insulators
• Mechanical Isolation of Highly Stable Antimonene under Ambient Conditions
• All "Magic Angles" Are "Stable" Topological
• Hourglass Fermions
• Irvsp: to obtain irreducible representations of electronic states in the VASP
• Potential ring of Dirac nodes in a new polymorph of Ca${}_3$P${}_2$
• Quantitative mappings between symmetry and topology in solids
• Building Blocks of Topological Quantum Chemistry: Elementary Band Representations
• Two-dimensional higher-order topology in monolayer graphdiyne
• Real Space Invariants: Twisted Bulk-Boundary Correspondence of Fragile Topology
• Experimental Discovery of the First Nonsymmorphic Topological Insulator KHgSb
• Fractional corner charges in spin-orbit coupled crystals
• Symmetry-Enforced Weyl Phonons
• Application of topological quantum chemistry in electrides
• Six-fold Excitations in Electrides
• Bulk NdNiO2 is thermodynamically unstable with respect to decomposition while hydrogenation reduces the instability and transforms it from metal to insulator
• Superconductivity in the Mn5Si3-type Zr5Sb3 system
• Higher-order topology in monolayer graphene
• Electronic structures and topological properties in nickelates $L{n}_{n+1}$Ni${}_n$O${}_{2n+2}$
• Buckled honeycomb group-$V$--$S_6$ symmetric $(d-2)$ higher order topological insulators
• High-throughput screening for Weyl Semimetals with S${}_4$ Symmetry

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• General theory of Josephson Diodes
• Liganded Xene as a Prototype of Two-Dimensional Stiefel-Whitney Insulators
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• Magnetic Electrides: High-Throughput Material Screening, Intriguing Properties, and Applications
• Catalogue of topological phonon materials
• Obstructed surface states as the origin of catalytic activity in inorganic heterogeneous catalysts
• Quadrupole topological insulators in Ta2M3Te5 (M= Ni, Pd) monolayers
• Ferroelectric higher-order topological insulator in two dimensions
• A robust and tunable Luttinger liquid in correlated edge of transition-metal second-order topological insulator Ta${}_2$Pd${}_3$Te${}_5$
• Large shift current, $\pi$ Zak phase and unconventional nature in Se and Te
• Evidence for an Excitonic Insulator State in Ta${}_2$Pd${}_3$Te${}_5$
• Spectroscopic signature of obstructed surface states in SrIn${}_2$P${}_2$
• Magnetic molecular orbitals in MnSi
• Large spin Hall conductivity and excellent hydrogen evolution reaction activity in unconventional PtTe1.75 monolayer
• From Atomic Semimetal to Topological Nontrivial Insulator
• Superconductivity in unconventional metals
• Abundant surface-semimetal phases in three-dimensional obstructed atomic insulators
• Orbital shift-induced boundary obstructed topological materials with a large energy gap
• Magnetic band representations, Fu-Kane-like symmetry indicators and magnetic topological materials
• Magnetic surface on nonmagnetic bulk of electride Hf2S
• Magnetic field filtering of the hinge supercurrent in unconventional metal NiTe${}_2$-based Josephson junctions
• Orbital doublet driven even-spin Chern insulators
• Majorana corner modes in unconventional monolayers of the 1T-PtSe2 family
• Observation of floating surface state in obstructed atomic insulator candidate NiP${}_2$
• Two-dimensional orbital-obstructed insulators with higher-order band topology
• The destiny of obstructed atomic insulator under correlation
• Unconventional phonon spectra and obstructed edge phonon modes
• Atomically thin obstructed atomic insulators with robust edge modes and quantized spin Hall effect
• Nodal higher-order topological superconductivity from C6-symmetric Dirac semimetals
• IRSSG: An Open-Source Software Package for Spin Space Groups