First-Principles Evaluation of the Potential of Borophene as a Monolayer Transparent Conductor

Two-dimensional boron is promising as a tunable monolayer metal for nano-optoelectronics. We study the optoelectronic properties of two likely allotropes of two-dimensional boron using first-principles density functional theory and many-body perturbation theory. We find that both systems are anisotropic metals, with strong energy- and thickness-dependent optical transparency and a weak (<1%) absorbance in the visible range. Additionally, using state-of-the-art methods for the description of the electron-phonon and electron-electron interactions, we show that the electrical conductivity is limited by electron-phonon interactions. Our results indicate that both structures are suitable as a transparent electrode.

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Pros and cons of time-dependent hybrid density functional approach to optical spectra of solids: a case study of CeO2

Physical Chemistry Chemical Physics ◽

10.1039/d1cp02049h ◽

2021 ◽

Author(s):

Huai-Yang Sun ◽

Shuo-Xue Li ◽

Hong Jiang

Keyword(s):

First Principles ◽

Density Functional ◽

Computational Cost ◽

Optical Spectra ◽

First Principles Calculation ◽

Many Body ◽

Many Body Perturbation Theory ◽

Pros And Cons ◽

Hybrid Density Functional

Prediction of optical spectra of complex solids remains a great challenge for first-principles calculation due to the huge computational cost of the state-of-the-art many-body perturbation theory based GW-Bethe Salpeter equation...

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Low-dimensional HfS2 as SO2 adsorbent and gas sensor: Effect of water and sulfur vacancies

Physical Chemistry Chemical Physics ◽

10.1039/d1cp04069c ◽

2021 ◽

Author(s):

Amina Bouheddadj ◽

Tarik Ouahrani ◽

Gbèdodé Wilfried KANNHOUNON ◽

Boufatah Reda ◽

Sumeya Bedrane ◽

...

Keyword(s):

Climate Change ◽

Density Functional Theory ◽

Dft Calculations ◽

Gas Sensor ◽

First Principles ◽

Density Functional ◽

Two Dimensional ◽

Functional Theory ◽

Sensor Effect ◽

Low Dimensional

First-principles based on density functional theory (DFT) calculations were performed to investigate the interaction of two-dimensional (2D) HfS2 with SO2, a harmful gas with implications for climate change. In particular,...

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A First-Principles Exploration of NaxSy Binary Phases at 1 atm and Under Pressure

Crystals ◽

10.3390/cryst9090441 ◽

2019 ◽

Vol 9 (9) ◽

pp. 441 ◽

Cited By ~ 3

Author(s):

Nisha Geng ◽

Tiange Bi ◽

Niloofar Zarifi ◽

Yan Yan ◽

Eva Zurek

Keyword(s):

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Elemental Sulfur ◽

Density Functional Theory Calculations ◽

Metastable Phases ◽

Van Der Waals Interactions ◽

Two Dimensional ◽

Functional Theory ◽

Battery Materials

Interest in Na-S compounds stems from their use in battery materials at 1 atm, as well as the potential for superconductivity under pressure. Evolutionary structure searches coupled with Density Functional Theory calculations were employed to predict stable and low-lying metastable phases of sodium poor and sodium rich sulfides at 1 atm and within 100–200 GPa. At ambient pressures, four new stable or metastable phases with unbranched sulfur motifs were predicted: Na2S3 with C 2 / c and Imm2 symmetry, C 2 -Na2S5 and C 2 -Na2S8. Van der Waals interactions were shown to affect the energy ordering of various polymorphs. At high pressure, several novel phases that contained a wide variety of zero-, one-, and two-dimensional sulfur motifs were predicted, and their electronic structures and bonding were analyzed. At 200 GPa, P 4 / m m m -Na2S8 was predicted to become superconducting below 15.5 K, which is close to results previously obtained for the β -Po phase of elemental sulfur. The structures of the most stable M3S and M4S, M = Na, phases differed from those previously reported for compounds with M = H, Li, K.

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Many-Body Effects in FeN4 Center Embedded in Graphene

Applied Sciences ◽

10.3390/app10072542 ◽

2020 ◽

Vol 10 (7) ◽

pp. 2542 ◽

Cited By ~ 1

Author(s):

Andrew Allerdt ◽

Hasnain Hafiz ◽

Bernardo Barbiellini ◽

Arun Bansil ◽

Adrian E. Feiguin

Keyword(s):

Transition Metal Complexes ◽

First Principles ◽

Density Functional ◽

Coulomb Repulsion ◽

Density Matrix Renormalization Group ◽

Orbital Interaction ◽

Many Body ◽

Generalized Gradient ◽

Functional Theory ◽

Density Matrix Renormalization

We introduce a computational approach to study porphyrin-like transition metal complexes, bridging density functional theory and exact many-body techniques, such as the density matrix renormalization group (DMRG). We first derive a multi-orbital Anderson impurity Hamiltonian starting from first principles considerations that qualitatively reproduce generalized gradient approximation (GGA)+U results when ignoring inter-orbital Coulomb repulsion U ′ and Hund exchange J. An exact canonical transformation is used to reduce the dimensionality of the problem and make it amenable to DMRG calculations, including all many-body terms (both intra- and inter-orbital), which are treated in a numerically exact way. We apply this technique to FeN 4 centers in graphene and show that the inclusion of these terms has dramatic effects: as the iron orbitals become single occupied due to the Coulomb repulsion, the inter-orbital interaction further reduces the occupation, yielding a non-monotonic behavior of the magnetic moment as a function of the interactions, with maximum polarization only in a small window at intermediate values of the parameters. Furthermore, U ′ changes the relative position of the peaks in the density of states, particularly on the iron d z 2 orbital, which is expected to affect the binding of ligands greatly.

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Width-dependent structural stability and magnetic properties of monolayer zigzag MoS2 nanoribbons

Modern Physics Letters B ◽

10.1142/s0217984917500178 ◽

2017 ◽

Vol 31 (03) ◽

pp. 1750017 ◽

Cited By ~ 7

Author(s):

Yan-Ni Wen ◽

Peng-Fei Gao ◽

Xi Chen ◽

Ming-Gang Xia ◽

Yang Zhang ◽

...

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

Structural Stability ◽

Magnetic Moment ◽

First Principles ◽

Density Functional ◽

Electronic States ◽

Two Dimensional ◽

Functional Theory ◽

Proportional Relationship

First-principles study based on density functional theory has been employed to investigate width-dependent structural stability and magnetic properties of monolayer zigzag MoS2 nanoribbons (ZZ-MoS2 NRs). The width N = 4–6 (the numbers of zigzag Mo–S chains along the ribbon length) are considered. The results show that all studied ZZ-MoS2 NRs are less stable than two-dimensional MoS2 monolayer, exhibiting that a broader width ribbon behaves better structural stability and an inversely proportional relationship between the structural stability (or the ribbon with) and boundary S–Mo interaction. Electronic states imply that all ZZ-MoS2 NRs exhibit magnetic properties, regardless of their widths. Total magnetic moment increases with the increasing width N, which is mainly ascribed to the decreasing S–Mo interaction of the two zigzag edges. In order to confirm this reason, a uniaxial tension strain is applied to ZZ-MoS2 NRs. It has been found that, with the increasing tension strain, the bond length of boundary S–Mo increases, at the same time, the magnetic moment increases also. Our results suggest the rational applications of ZZ-MoS2 NRs in nanoelectronics and spintronics.

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Carrier-mediated ferromagnetism in two-dimensional PtS2

RSC Advances ◽

10.1039/c9ra09756b ◽

2020 ◽

Vol 10 (2) ◽

pp. 952-957 ◽

Cited By ~ 3

Author(s):

Konstantina Iordanidou ◽

Michel Houssa ◽

Clas Persson

Keyword(s):

Density Functional Theory ◽

Electronic Properties ◽

First Principles ◽

Density Functional ◽

Hole Doping ◽

Two Dimensional ◽

First Principles Calculations ◽

Functional Theory ◽

The Impact

Using first principles calculations based on density functional theory the impact of hole doping on the magnetic and electronic properties of two dimensional PtS2 is studied.

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A New Class of Scandium Carbide Nanosheet

Scientific Reports ◽

10.1038/s41598-019-52882-3 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Jing Wang ◽

Tian-Tian Liu ◽

Chen-Ling Li ◽

Ying Liu

Keyword(s):

First Principles ◽

Density Functional ◽

Storage Capacity ◽

Two Dimensional ◽

Primitive Cell ◽

Hydrogen Storage Capacity ◽

Functional Theory ◽

Average Binding Energy ◽

New Class ◽

Hydrogen Molecules

Abstract A new class of two-dimensional scandium carbide nanosheet has been identified by using first-principles density functional theory. It has a primitive cell of Sc3C10, in which there are two pentagonal carbon rings surrounded by one scandium octagon. Being as the precussor of Volleyballene Sc20C60 and ScC nanotubes, the Sc3C10 nanosheet is exceptionally stable. By rolling up this Sc3C10 sheet, a series of stable ScC nanotubes have been obtained. All the nanotubes studied have been found to be metallic. Furthermore, the hydrogen storage capacity of the ScC nanotubes has been explored. The calculated results show that one unit of the (0,3) ScC nanotube can adsorb a maximum of 51 hydrogen molecules, reaching up to a 6.25 wt% hydrogen gravimetric density with an average binding energy of 0.23 eV/H2.

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