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The era of exascale computing presents both exciting opportunities and unique challenges for quantum mechanical simulations. While the transition from petaflops to exascale computing has been marked by a steady increase in computational power, the shift towards heterogeneous architectures, particularly the dominant role of graphical processing units (GPUs), demands a fundamental shift in software development strategies. This review examines the changing landscape of hardware and software for exascale computing, highlighting the limitations of traditional algorithms and software implementations in light of the increasing use of heterogeneous architectures in high-end systems. We discuss the challenges of adapting quantum chemistry software to these new architectures, including the fragmentation of the software stack, the need for more efficient algorithms (including reduced precision versions) tailored for GPUs, and the importance of developing standardized libraries and programming models.
We introduce a novel three-body correlation factor that is designed to vanish in the core region around each nucleus and approach a universal two-body correlation factor for valence electrons. The Transcorrelated Hamiltonian is used to optimize the orbitals of a single Slater determinant within a biorthonormal framework. The Slater-Jastrow wave function is optimized on a set of atomic and molecular systems containing both second-row elements and $3d$ transition metal elements. The optimization of the correlation factor and the orbitals, along with increasing the basis set, results in a systematic lowering of the Variational Monte Carlo energy for all systems tested. Importantly, the optimal parameters of the correlation factor obtained for atomic systems are transferable to molecules. Additionally, the present correlation factor is computationally efficient, using a mixed analytical-numerical integration scheme that reduces the costly numerical integration from $\mathbb{R}^6$ to $\mathbb{R}^3$.
<div xmlns="http://www.tei-c.org/ns/1.0"><p>A program is a function p : input -→ output If the output of a program p 1 is of the same type as the input of a program p 2 , we can define a new program p 3 = p 2 • p</p></div>
Sujets
Atrazine
Diatomic molecules
3115aj
Petascale
Anderson mechanism
BIOMOLECULAR HOMOCHIRALITY
Approximation GW
Green's function
Corrélation électronique
3470+e
Excited states
ALGORITHM
Line formation
Biodegradation
Coupled cluster
Large systems
Spin-orbit interactions
3115vj
Argon
Single-core optimization
Ab initio calculation
Relativistic corrections
X-ray spectroscopy
QSAR
Acrolein
CIPSI
Wave functions
Azide Anion
Density functional theory
Dipole
Atrazine-cations complexes
Molecular descriptors
BSM physics
Carbon Nanotubes
Argile
Atomic and molecular structure and dynamics
Range separation
3115am
Atomic and molecular collisions
Time reversal violation
Aimantation
Molecular properties
Quantum Monte Carlo
A priori Localization
CP violation
Fonction de Green
Configuration Interaction
Dirac equation
Atom
Chimie quantique
Relativistic quantum mechanics
Configuration interaction
Configuration interactions
Auto-énergie
Atomic charges
Atomic data
États excités
Adiabatic connection
3115ag
Coupled cluster calculations
Parity violation
Diffusion Monte Carlo
Pesticide
AROMATIC-MOLECULES
Xenon
Numerical calculations
New physics
Analytic gradient
Quantum Chemistry
Relativistic quantum chemistry
Time-dependent density-functional theory
Electron correlation
Chemical concepts
BENZENE MOLECULE
3115bw
Parallel speedup
Valence bond
Ion
Electron electric moment
AB-INITIO
Mécanique quantique relativiste
Quantum chemistry
AB-INITIO CALCULATION
Théorie des perturbations
Atoms
Hyperfine structure
Electron electric dipole moment
Polarizabilities
Pesticides Metabolites Clustering Molecular modeling Environmental fate Partial least squares
3115ae
3315Fm
A posteriori Localization
Atomic charges chemical concepts maximum probability domain population
Atomic processes
Perturbation theory
Ground states
Rydberg states
3115vn
Abiotic degradation
Dispersion coefficients