Home

Person

Alfredo Pasquarello

About
Privacy
Disclaimer

Graph Chatbot

Related publications (226)

Liquid Water through Density-Functional Molecular Dynamics: Plane-Wave vs Atomic-Orbital Basis Sets

Alfredo Pasquarello, Giacomo Francesco Leonardo Miceli

We determine and compare structural, dynamical, and electronic properties of liquid water at near ambient conditions through density-functional molecular dynamics simulations, when using either plane-wave or atomic-orbital basis sets. In both frameworks, t ...

Amer Chemical Soc2016

Self-compensation due to point defects in Mg-doped GaN

Alfredo Pasquarello, Giacomo Francesco Leonardo Miceli

Using hybrid density functional theory, we address point defects susceptible to cause charge compensation upon Mg doping of GaN. We determine the free energy of formation of the nitrogen vacancy and of several Mg-related defects. The entropic contribution ...

Amer Physical Soc2016

Giant apparent lattice distortions in STM images of corrugated sp2-hybridised monolayers

Laurent Claude, Harald Brune, Alfredo Pasquarello, François Patthey, Stefano Rusponi, Anne Lehnert, Quentin Dubout, Markus Etzkorn, Donat Fabian Natterer

We report on the strengths and limitations of scanning tunnelling microscopy (STM) when used for characterising atomic-scale features of quasi two-dimensional materials, such as graphene and single layers of hexagonal boron nitride, which may present stron ...

Institute of Physics (IoP) and Deutsche Physikalische Gesellschaft2016

Oxygen defects in GaAs: A hybrid functional study

Alfredo Pasquarello, Davide Colleoni

Using hybrid density functional calculations, we address the structural properties, formation energies, and charge transition levels of a variety of oxygen defects in GaAs. The set of considered defects comprises the bridging O atom in a As-O-Ga configurat ...

Amer Physical Soc2016

Absolute deformation potentials of two-dimensional materials

Alfredo Pasquarello, Julia Anna Wiktor

We present ab initio calculations of uniaxial absolute deformation potentials of the valence and the conduction bands in monolayer MoS2, MoSe2, WS2, WSe2, h-BN, and phosphorene. Calculations are performed using both semilocal and hybrid functionals. The ab ...

Amer Physical Soc2016

Oxygen defects in amorphous Al2O3: A hybrid functional study

Alfredo Pasquarello, Zhendong Guo, Francesco Ambrosio

The electronic properties of the oxygen vacancy and interstitial in amorphous Al2O3 are studied via ab initio molecular dynamics simulations and hybrid functional calculations. Our results indicate that these defects do not occur in amorphous Al2O3, due to ...

American Institute of Physics2016

Diffusion of interstitial oxygen in silicon and germanium: A hybrid functional study

Alfredo Pasquarello, Davide Colleoni

The minimum-energy paths for the diffusion of an interstitial O atom in silicon and germanium are studied through the nudged-elastic-band method and hybrid functional calculations. The reconsideration of the diffusion of O in silicon primarily serves the p ...

2016

Structural, Dynamical, and Electronic Properties of Liquid Water: A Hybrid Functional Study

Alfredo Pasquarello, Giacomo Francesco Leonardo Miceli, Francesco Ambrosio

We study structural, dynamical, and electronic properties of liquid water through ab initio molecular dynamics (MD) simulations based on a hybrid functional which includes nonlocal van der Waals (vdW) interactions. The water dimer, the water hexamer, and t ...

Amer Chemical Soc2016

Ab initio Electronic Structure of Liquid Water

Alfredo Pasquarello, Wei Chen, Giacomo Francesco Leonardo Miceli, Francesco Ambrosio

Self-consistent GW calculations with efficient vertex corrections are employed to determine the electronic structure of liquid water. Nuclear quantum effects are taken into account through ab initio path-integral molecular dynamics simulations. We reveal a ...

American Physical Society2016

First-principles determination of defect energy levels through hybrid density functionals and GW

Alfredo Pasquarello, Wei Chen

In this topical review, we discuss recent progress in electronic-structure methods for calculating defect energy levels in semiconductors and insulators. We concentrate mainly on two advanced electronic-structure schemes, namely hybrid density functional t ...

Institute of Physics2015

Band alignment and chemical bonding at the GaAs/Al2O3 interface: A hybrid functional study

Alfredo Pasquarello, Davide Colleoni, Giacomo Francesco Leonardo Miceli

The band alignment at the interface between GaAs and amorphous Al2O3 is studied through the use of hybrid functionals. For the oxide component, a disordered model is generated through density-functional molecular dynamics. The achieved structure shows good ...

2015

Accurate band gaps of extended systems via efficient vertex corrections in GW

Alfredo Pasquarello, Wei Chen

We propose the use of an approximate bootstrap exchange-correlation kernel to account for vertex corrections in self-consistent GW calculations. We show that the approximate kernel gives accurate band gaps for a variety of extended systems, including simpl ...

2015

Fermi-level pinning through defects at GaAs/oxide interfaces: A density functional study

Alfredo Pasquarello, Davide Colleoni, Giacomo Francesco Leonardo Miceli

Using density functional calculations, we study a set of candidate defects for Fermi-level pinning at GaAs/oxide interfaces. The set of considered defects comprises both bulklike and interfacial defects, including As antisites, Ga and As dangling bonds, th ...

American Physical Society2015

Interfacial Ga-As suboxide: Structural and electronic properties

Alfredo Pasquarello, Davide Colleoni

The structural and electronic properties of Ga-As suboxide representative of the transition region at the GaAs/oxide interface are studied through density functional calculations. Two amorphous models generated by quenches from the melt are taken under con ...

American Institute of Physics2015

Redox levels in aqueous solution: Effect of van der Waals interactions and hybrid functionals

Alfredo Pasquarello, Giacomo Francesco Leonardo Miceli, Francesco Ambrosio

We investigate redox levels in aqueous solution using a combination of ab initio molecular dynamics (MD) simulations and thermodynamic integration methods. The molecular dynamics are performed with both the semilocal Perdew-Burke-Ernzerhof functional and a ...

2015

Energetics of native point defects in GaN: A density-functional study

Alfredo Pasquarello, Giacomo Francesco Leonardo Miceli

We study the formation energies of native point defects in GaN through density-functional theory. In our first-principles scheme, the band edges are positioned in accord with hybrid density functional calculations, thus yielding a band-gap in agreement wit ...

Elsevier2015

Arsenic related defect states resonant with the semiconductor conduction band at the In0.53Ga0.47As/oxide interface: A density functional study

Alfredo Pasquarello, Davide Colleoni, Giacomo Francesco Leonardo Miceli

An arsenic related defect at the In0.53Ga0.47As/oxide interface is studied through density functional theory. This defect corresponds to an As-As timer which transforms into two doubly occupied As dangling bonds upon capture of two electrons. The defect ch ...

Elsevier2015

Isobaric first-principles molecular dynamics of liquid water with nonlocal van der Waals interactions

Alfredo Pasquarello, Giacomo Francesco Leonardo Miceli

We investigate the structural properties of liquid water at near ambient conditions using first-principles molecular dynamics simulations based on a semilocal density functional augmented with nonlocal van der Waals interactions. The adopted scheme offers ...

American Institute of Physics2015

Band-edge positions in GW: Effects of starting point and self-consistency

Alfredo Pasquarello, Wei Chen

We study the effect of starting point and self-consistency within GW on the band-edge positions of semiconductors and insulators. Compared to calculations based on a semilocal starting point, the use of a hybrid-functional starting point shows a larger qua ...

2014

Minimum energy path and atomistic mechanism of the elementary step in oxygen diffusion in silicon: A density-functional study

Alfredo Pasquarello, Jan Felix Binder

Using a density-functional scheme, we study the migration of a single O atom in a (110) plane between two adjacent bond-center sites in bulk Si. The minimum energy migration path is found through the nudged elastic band method within a generalized gradient ...

American Physical Society2014

Page 5 of 12