Although the self-assembly of organic ligands on gold has been dominated by sulfur-based for decades, a new ligand class, N-heterocyclic carbenes (NHCs), appeared as an interesting alternative. However, fundamental questions surrounding this remain unanswered. Herein, we describe effect NHC structure, surface coverage, and substrate temperature mobility, thermal stability, geometry, self-assembly. Analysis adsorption scanning tunneling microscopy density functional theory have revealed...

A monolayer of CrI3 is a two-dimensional crystal in its equilibrium configuration ferromagnetic semiconductor. In contrast, two coupled layers can be ferromagnetic, or antiferromagnetic depending on the stacking. We study magnetic phase diagram upon strain antiferromagnetically bilayer with C2/m symmetry. found that an efficient tool to tune structure. tensile stabilizes phase, while compressive turns system ferromagnetic. associate behavior relative displacement between induced by strain....

In$_2$Se$_3$ is a semiconductor material that can be stabilized in different crystal structures (at least one 3D and several 2D layered have been reported) with diverse electrical optical properties. This feature has plagued its characterization over the years, reported band gaps varying an unacceptable range of 1 eV. Using first-principles calculations based on density functional theory HSE06 hybrid functional, we investigated structural electronic properties four phases In$_2$Se$_3$,...

Crystalline ${\mathrm{Bi}}_{2}{\mathrm{Se}}_{3}$ is one of the most explored three-dimensional (3D) topological insulators with a $0.3\phantom{\rule{0.28em}{0ex}}\mathrm{eV}$ energy gap making it promising for applications. Its amorphous counterpart could bring to light new possibilities large scale synthesis and Using ab initio molecular dynamics simulations, we have studied realistic phases generated by different processes melting, quenching, annealing. Extensive structural electronic...

Materials with designed properties arises in a synergy between theoretical and experimental approaches. In this study we explore the set of Archimedean lattices forming guidance to its electronic topological phases. Within these lattices, rich structure emerge type-I II Dirac fermions, flat bands high-degeneracy points linear dispersions. Employing tight-binding model, spin-orbit coupling, characterize quantum spin Hall (QSH) phase all lattices. Our discussion is validated within density...

We investigate the interplay between confinement and fermion doubling problem in Dirac-like Hamiltonians. Individually, both features are well known. First, simple electrostatic gates do not confine electrons due to Klein tunneling. Second, a typical lattice discretization of first-order derivative $k\ensuremath{\rightarrow}\ensuremath{-}i{\ensuremath{\partial}}_{x}$ skips central point allow spurious low-energy, highly oscillating solutions known as doublers. While no-go theorem states that...

We investigate the layer localization control of two-dimensional states in multilayer metal-organic frameworks (MOFs). For finite stackings (NiC4S4)3 MOFs, weak van der Waals coupling between adjacent layers leads to a Fermi level dependent distribution electronic monolayers. Such is reflected topological edge nanoribbons. Moreover, by applying an external electric field parallel stacking direction, spatial can be controlled for chosen energy. This behavior studied comparing density...

We have studied how a generic bilayer kagome lattice behaves upon layer rotation. employed tight-binding model with one orbital per site and found: (i) for low rotational angles at energies, the same flat bands structure, such as in twisted graphene; although, larger value of magic angle. Moreover, (ii) high energies due to superstructure symmetry regions, we found characteristic three-band dispersion lattice. In latter, its bandwidth decreases lower confining them within few meV. Therefore,...

Recently, orbital-textures have been found in Rashba and topological insulator (TI) surface states as a result of the spin-orbit coupling (SOC). Here, we predict px/py orbital texture, linear dispersive Dirac bands, arising at K/K' points χ-h0 borophene chiral monolayer. Combining "first-principles" calculations with effective Hamiltonians, show that pseudospin has its direction locked momentum similar way TIs' spin-textures. Additionally, considering layer degree freedom, this lattice...

Understanding the role of microscopic attributes in nanocomposites allows for a controlled and, therefore, acceleration experimental system designs. In this work, we extracted relevant parameters controlling graphene oxide binding strength to cellulose by combining first-principles calculations and machine learning algorithms. We were able classify systems among two classes with higher lower energies, which are well defined based on isolated features. By theoretical X-ray photoelectron...

Currently, solid interfaces composed of two-dimensional materials (2D) in contact with metal surfaces (m-surf) have been the subject intense research, where borophene bilayer (BBL) has considered a prominent material for development electronic devices based on 2D platforms. In this work, we present theoretical study energetic, structural, and properties BBL/m-surf interface, m-surf = Ag(111), Au(111), Al(111) surfaces, transport BBL channels connected to top contacts. We find that becomes...

We have investigated the energetic stability and electronic properties of metal-organic topological insulators bilayers (BLs), $(MC_4S_4)_3$-BL, with M=Ni Pt, using first-principles calculations tight-binding model. Our findings show that $(MC_4S_4)_3$-BL is an appealing platform to perform band structure engineering, based on topologically protected chiral edge states. The BLs ruled by van der Waals interactions; being AA stacking energetically most stable one. characterized a combination...

Jacutingate, a recently discovered Brazilian naturally occurring mineral, has shown to be the first experimental realization of Kane-Mele topological model. In this letter we have unveiled class materials $M_2NX_3$ ($M$=Ni, Pt, Pd; $N$=Zn, Cd, Hg; and $X$=S, Se, Te), sharing jacutingaite's key features, i.e., high stability, phase. By employing first-principles calculations extensively characterize energetic stability while showing common occurrence Here found Pt-based surpassing impressive...

Understanding the effects of atomic structure modification in hematite photoanodes is essential for rational design high-efficiency functionalizations. Recently, it was found that interface with Sn/Sb segregates considerably increases photocatalytic efficiency. However, understanding different electronic these modifications at level still lacking. This Letter describes segregation two dopants–Sn and Sb–on both solid–solid (grain boundaries) solid–liquid interfaces (surfaces) hematite. Within...

Charge transfer between metal–organic Kagome lattices interfaced with graphene provides a tunable quantum anomalous Hall effect.

Observation of large nonsaturating magnetoresistance in rare-earth monopnictides has raised enormous interest understanding the role its electronic structure. Here, by a combination molecular-beam epitaxy, low-temperature transport, angle-resolved photoemission spectroscopy, and hybrid density functional theory we have unveiled band structure LuSb, where electron-hole compensation is identified as mechanism responsible for this topologically trivial compound. In contrast to bulk single...

Two-dimensional transition metal dichalcogenides (MX$_2$) vacancy formation energetics is extensively investigated. Within an ab-initio approach we study the MX$_2$ systems, with M=Mo, W, Ni, Pd and Pt, X=S, Se, Te. Here classify that chalcogen vacancies are always energetic favorable over ones. However, for late metals $4d$, Pt $5d$ experimentally achievable, bringing up localized magnetic moments within semiconducting matrix. By quantifying localization of states evidentiate it rules...

Spin-orbital texture in topological insulators due to the spin locking with electron momentum play an important role spintronic phenomena that arise from interplay between charge and degrees of freedom. We have explored interfaces a ferromagnetic system $({\mathrm{CrI}}_{3})$ insulator $({\mathrm{Bi}}_{2}{\mathrm{Se}}_{3})$ allow manipulation spin-orbital texture. Within ab initio approach we extracted spin-orbital-texture dependence experimentally achievable interface designs. The presence...

The discovery of the quantum spin Hall effect led to exploration electronic transport for spintronic devices. Here, we theoretically investigated conductance in large-gap realistic system, Pt$_2$HgSe$_3$ nanoribbons. By an ab initio approach, found that edge states present a penetration depth about $0.9$\,{nm}, which is much smaller than those predicted other 2D topological systems. Thus, suggesting allows exploitation properties narrow ribbons. Using non-equilibrium Green's functions...

We report experimental investigations of spin-to-charge current conversion and charge transfer (CT) dynamics at the interface graphene/WS

Transition metal dichalcogenides have been the subject of numerous studies addressing technological applications and fundamental issues. Single-layer PtSe2 is a semiconductor with trivial bandgap, in contrast, its counterpart 25% Se atoms substituted by Hg, Pt2HgSe3 (jacutingaite, naturally occurring mineral), 2D topological insulator large bandgap. Based on ab-initio calculations, we investigate energetic stability, transition Pt(HgxSe1-x)2 as function alloy concentration, distribution Hg...

We report experimental investigations of spin-to-charge current conversion and charge transfer dynamics (CT) at the interface graphene/WS$_2$ van der Waals heterostructure. Pure spin was produced by precession in microwave-driven ferromagnetic resonance a permalloy film (Py-Ni$_{81}$Fe$_{19}$) injected into heterostructure through pumping process. The observed is attributed to inverse Rashba-Edelstein effect (IREE) interface. Interfacial CT this investigated based on framework...

Space-group symmetries dictate the energy degeneracy of quasiparticles (e.g., electronic, photonic) in crystalline structures. For spinless systems, there can only be double or triple degeneracies protected by these symmetries, while other are usually taken as accidental. In this Rapid Communication we show that it is possible to design higher exploring site permutation symmetries. These principles shown satisfied previously studied lattices, and new structures proposed with three, four,...

Two-dimensional arsenic allotropes have been grown on metallic surfaces, while topological properties theoretically described strained structures. Here, we experimentally grow arsenene by molecular beam epitaxy over the insulating SiC substrate. The presents a flat structure with strain field that follows surface periodicity. Our ab initio simulations, based density functional theory, corroborate experimental observation. new allotrope triangular structure, rather than honeycomb previously...