Quantum ESPRESSO: One Further Step toward the Exascale

Abstract

We review the status of the Quantum ESPRESSO software suite for electronic-structure calculations based on plane waves, pseudopotentials, and density-functional theory. We highlight the recent developments in the porting to GPUs of the main codes, using an approach based on OpenACC and CUDA Fortran offloading. We describe, in particular, the results achieved on linear-response codes, which are one of the distinctive features of the Quantum ESPRESSO suite. We also present extensive performance benchmarks on different GPU-accelerated architectures for the main codes of the suite.

Excited State Properties of Point Defects in Semiconductors and Insulators Investigated with Time-Dependent Density Functional Theory

“…The electronic structures of the defects in diamond, 4H–SiC, and MgO are obtained using DFT and the plane-wave pseudopotential method as implemented in the Quantum ESPRESSO package. , The plane-wave energy cutoff was set to 60 Ry. We used the semilocal functional by Perdew, Burke, and Ernzerhof (PBE) and the DDH functional. , The fraction of exact exchange used in the DDH functional was determined by the inverse of the macroscopic dielectric constant of the system, resulting in 18, 15, and 36% of exact exchange for diamond, 4H–SiC, and MgO, respectively. , …”

“…Each GPU node of Perlmutter is equipped with one AMD EPYC Milan CPU and four NVIDIA A100 GPUs. To benchmark the implementation of WEST-TDDFT, we considered the first excited state of the NV – in diamond, whose ground-state DFT calculation was performed using the Quantum ESPRESSO , code (version 7.2), the SG15 optimized norm-conserving Vanderbilt (ONCV) pseudopotentials, , and the DDH functional. , A kinetic energy cutoff of 60 Ry was used for the plane-wave basis set. The Brillouin zone was sampled with the Γ-point.…”

Mechanism of Charge Transport in Lithium Thiophosphate

“…We constructed the training set for the ML models in an iterative fashion. A starting data set of structures is generated by running NVT Car–Parrinello Molecular Dynamics with the PBEsol functional as provided by the Quantum ESPRESSO package, − for a set of selected temperatures (250, 500, and 1000 K) and volumes. This initial data set is then computed via more converged single-point DFT calculations with the PBEsol functional.…”

Electronic, optical, and adsorption properties of Li-doped hexagonal boron nitride: a GW approach

“…Density functional theory (DFT) based on the plane-wave pseudopotential, as implemented by the PWSCF code of the Quantum Espresso software package, was used for the calculations. 26–29 The generalised gradient approximation with Perdew–Burke–Ernzerhof parameterization (GGA-PBE) was used to deal with the exchange–correlation functional. 30 The kinetic energy cutoff for wavefunctions (ecutwfc) and charge density cutoff (ecutrho) were set to 50 Ry and 300 Ry, respectively.…”