QUESTDB: A database of highly accurate excitation energies for the electronic structure community
We describe our efforts of the past few years to create a large set of more than 500 highly
accurate vertical excitation energies of various natures (π→ π*, n→ π*, double excitation …
accurate vertical excitation energies of various natures (π→ π*, n→ π*, double excitation …
QMCPACK: an open source ab initio quantum Monte Carlo package for the electronic structure of atoms, molecules and solids
QMCPACK is an open source quantum Monte Carlo package for ab initio electronic
structure calculations. It supports calculations of metallic and insulating solids, molecules …
structure calculations. It supports calculations of metallic and insulating solids, molecules …
Variational and diffusion quantum Monte Carlo calculations with the CASINO code
RJ Needs, MD Towler, ND Drummond… - The Journal of …, 2020 - pubs.aip.org
We present an overview of the variational and diffusion quantum Monte Carlo methods as
implemented in the casino program. We particularly focus on developments made in the last …
implemented in the casino program. We particularly focus on developments made in the last …
Interactions between large molecules pose a puzzle for reference quantum mechanical methods
Quantum-mechanical methods are used for understanding molecular interactions
throughout the natural sciences. Quantum diffusion Monte Carlo (DMC) and coupled cluster …
throughout the natural sciences. Quantum diffusion Monte Carlo (DMC) and coupled cluster …
Quantum package 2.0: An open-source determinant-driven suite of programs
Quantum chemistry is a discipline which relies heavily on very expensive numerical
computations. The scaling of correlated wave function methods lies, in their standard …
computations. The scaling of correlated wave function methods lies, in their standard …
[HTML][HTML] Fast semistochastic heat-bath configuration interaction
This paper presents in detail our fast semistochastic heat-bath configuration interaction
(SHCI) method for solving the many-body Schrödinger equation. We identify and eliminate …
(SHCI) method for solving the many-body Schrödinger equation. We identify and eliminate …
[HTML][HTML] Excited states using semistochastic heat-bath configuration interaction
We extend our recently developed heat-bath configuration interaction (HCI) algorithm, and
our semistochastic algorithm for performing multireference perturbation theory, to calculate …
our semistochastic algorithm for performing multireference perturbation theory, to calculate …
Excited states of methylene, polyenes, and ozone from heat-bath configuration interaction
The electronically excited states of methylene (CH2), ethylene (C2H4), butadiene (C4H6),
hexatriene (C6H8), and ozone (O3) have long proven challenging due to their complex …
hexatriene (C6H8), and ozone (O3) have long proven challenging due to their complex …
[HTML][HTML] Almost exact energies for the Gaussian-2 set with the semistochastic heat-bath configuration interaction method
The recently developed semistochastic heat-bath configuration interaction (SHCI) method is
a systematically improvable selected configuration interaction plus perturbation theory …
a systematically improvable selected configuration interaction plus perturbation theory …
Orbital optimization in selected configuration interaction methods
We study several approaches to orbital optimization in selected configuration interaction
(SCI) plus perturbation theory methods and test them on the ground and excited states of …
(SCI) plus perturbation theory methods and test them on the ground and excited states of …