A meta-GGA level screened range-separated hybrid functional by employing short range Hartree–Fock with a long range semilocal functional

2018 ◽  
Vol 20 (13) ◽  
pp. 8999-9005 ◽  
Author(s):  
Subrata Jana ◽  
Prasanjit Samal
Keyword(s):  
Solid State ◽  
Long Range ◽  
Short Range ◽  
Density Functionals ◽  
Hybrid Functional ◽  
Hartree Fock ◽  
Wide Range

The range-separated hybrid density functionals are very successful in describing a wide range of molecular and solid-state properties accurately.

Importance of short-range versus long-range Hartree-Fock exchange for the performance of hybrid density functionals

2006 ◽  
Vol 125 (7) ◽  
pp. 074106 ◽  
Author(s):  
Oleg A. Vydrov ◽  
Jochen Heyd ◽  
Aliaksandr V. Krukau ◽  
Gustavo E. Scuseria
Keyword(s):  
Long Range ◽  
Short Range ◽  
Density Functionals ◽  
Hartree Fock

Solid State NMR as A Probe of Inorganic Materials:Examples From Glasses and Sol-Gels

2006 ◽  
Vol 984 ◽  
Author(s):  
Paul Guerry ◽  
Donna L Carroll ◽  
Phillips N Gunawidjaja ◽  
Prodipta Bhattacharya ◽  
Daniela Carta ◽  
...  
Keyword(s):  
Solid State ◽  
Phosphate Glass ◽  
Solid State Nmr ◽  
Short Range ◽  
Sol Gel ◽  
The Other ◽  
Disordered Materials ◽  
Structural Sensitivity ◽  
Nmr Data ◽  
Wide Range

AbstractTo understand amorphous and structurally disordered materials requires the application of a wide-range of advanced physical probe techniques and herein a combined methodology is outlined. The relatively short-range structural sensitivity of solid state NMR means that it is a core probe technique for characterizing such materials. The aspects of the solid state NMR contribution are emphasized here with examples given from a number of systems, with especial emphasis on the information available from 17O NMR in oxygen-containing materials. 17O NMR data for crystallization of pure sol-gel prepared oxides is compared, with new data presented from In2O3 and Sc2O3. Sol-gel formed oxide mixtures containing silica have been widely studied, but again the role and effect of the other added oxide varies widely. In a ternary ZrO2-TiO2-SiO2 silicate sol-gel the level of Q4 formation is dependent not only on the composition, as expected, but also the nature of the second added oxide. Sol-gel formed phosphates have been much less widely studied than silicates and some 31P NMR data from xerogel, sonogel and melt-quench glasses of the same composition are compared. The effect of small amounts of added antibacterial copper on phosphate glass networks is also explored.

scholarly journals Monte Carlo Study of Electronic Transport in Monolayer InSe

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4210 ◽  
Author(s):  
Sanjay Gopalan ◽  
Gautam Gaddemane ◽  
Maarten L. Van de Put ◽  
Massimo V. Fischetti
Keyword(s):  
Monte Carlo ◽  
Long Range ◽  
Electron Mobility ◽  
Short Range ◽  
Field Effect Transistors ◽  
2D Materials ◽  
Matrix Elements ◽  
Electronic Band ◽  
Low Field ◽  
Wide Range

The absence of a band gap in graphene makes it of minor interest for field-effect transistors. Layered metal chalcogenides have shown great potential in device applications thanks to their wide bandgap and high carrier mobility. Interestingly, in the ever-growing library of two-dimensional (2D) materials, monolayer InSe appears as one of the new promising candidates, although still in the initial stage of theoretical studies. Here, we present a theoretical study of this material using density functional theory (DFT) to determine the electronic band structure as well as the phonon spectrum and electron-phonon matrix elements. The electron-phonon scattering rates are obtained using Fermi’s Golden Rule and are used in a full-band Monte Carlo computer program to solve the Boltzmann transport equation (BTE) to evaluate the intrinsic low-field mobility and velocity-field characteristic. The electron-phonon matrix elements, accounting for both long- and short-range interactions, are considered to study the contributions of different scattering mechanisms. Since monolayer InSe is a polar piezoelectric material, scattering with optical phonons is dominated by the long-range interaction with longitudinal optical (LO) phonons while scattering with acoustic phonons is dominated by piezoelectric scattering with the longitudinal (LA) branch at room temperature (T = 300 K) due to a lack of a center of inversion symmetry in monolayer InSe. The low-field electron mobility, calculated considering all electron-phonon interactions, is found to be 110 cm2V−1s−1, whereas values of 188 cm2V−1s−1 and 365 cm2V−1s−1 are obtained considering the long-range and short-range interactions separately. Therefore, the calculated electron mobility of monolayer InSe seems to be competitive with other previously studied 2D materials and the piezoelectric properties of monolayer InSe make it a suitable material for a wide range of applications in next generation nanoelectronics.

Combining long-range configuration interaction with short-range density functionals

1997 ◽  
Vol 275 (3-4) ◽  
pp. 151-160 ◽  
Author(s):  
Thierry Leininger ◽  
Hermann Stoll ◽  
Hans-Joachim Werner ◽  
Andreas Savin
Keyword(s):  
Long Range ◽  
Configuration Interaction ◽  
Short Range ◽  
Density Functionals ◽  
Range Density

Coupling of Short-range Density-functional with Long-range Post-Hartree-Fock Methods

2010 ◽  
Vol 224 (3-4) ◽  
pp. 481-491 ◽  
Author(s):  
Erich Goll ◽  
Hans-Joachim Werner ◽  
Hermann Stoll
Keyword(s):  
Long Range ◽  
Short Range ◽  
Density Functional ◽  
Hartree Fock ◽  
Range Density

Point perturbations

2020 ◽  
pp. 248-291
Author(s):  
Sandip Tiwari
Keyword(s):  
Long Range ◽  
Short Range ◽  
Tight Binding ◽  
Lattice Energy ◽  
Hartree Fock ◽  
Deep Centers ◽  
Localized State ◽  
Molecule Model ◽  
Extrinsic Defects ◽  
Defect Behavior

This chapter discusses the energetics of point perturbations arising from intrinsic and extrinsic defects, and intentional and unintentional impurities. Point perturbations can be short range or long range. This requires the inclusion of core potential, exchange correlation and Hartree or Hartree-Fock potential. Hubbard energy, which is useful for Hartree calculations in a localized state, is introduced. An approach to calculating the behavior arising in shallow dopants (long range) and deep centers (short range) is presented. The tight binding defect-molecule model is used to explore the appearance of bonding and antibonding states in vacancies, interstitials and substitutional deep centers and some common complexes, such as the DX center, using configuration coordinates to understand the electronic and lattice energy contributions in the defect behavior. Finally, the chapter summarizes other important centers, such as the Pb center and the F center, before reviewing the implications of centers in light interaction and Poole-Frenkel conduction.

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