Journal ArticleDOI
The ORCA program system
TLDR
An overview of the current possibilities of ORCA is provided and its efficiency is documents.Abstract:
ORCA is a general-purpose quantum chemistry program package that features virtually all modern electronic structure methods (density functional theory, many-body perturbation and coupled cluster theories, and multireference and semiempirical methods). It is designed with the aim of generality, extendibility, efficiency, and user friendliness. Its main field of application is larger molecules, transition metal complexes, and their spectroscopic properties. ORCA uses standard Gaussian basis functions and is fully parallelized. The article provides an overview of its current possibilities and documents its efficiency. © 2011 John Wiley & Sons, Ltd.read more
Citations
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Journal ArticleDOI
Software update: the ORCA program system, version 4.0
TL;DR: This short update provides an overview of the capabilities that have been added to the ORCA electronic structure package (version 4.0) since publication of the first article in 2012.
Journal ArticleDOI
An overview of the Amber biomolecular simulation package
TL;DR: The most recent developments, since version 9 was released in April 2006, of the Amber and AmberTools MD software packages are outlined, referred to here as simply the Amber package.
Journal ArticleDOI
The ORCA quantum chemistry program package
TL;DR: In this contribution to the special software-centered issue, the ORCA program package is described, which is a widely used program in various areas of chemistry and spectroscopy with a current user base of over 22 000 registered users in academic research and in industry.
Journal ArticleDOI
Scalable molecular dynamics on CPU and GPU architectures with NAMD.
James C. Phillips,David J. Hardy,Julio D.C. Maia,John E. Stone,João V. Ribeiro,Rafael C. Bernardi,Ronak Buch,Giacomo Fiorin,Jérôme Hénin,Wei Jiang,Ryan McGreevy,Marcelo C. R. Melo,Brian K. Radak,Robert D. Skeel,Abhishek Singharoy,Yi Wang,Benoît Roux,Aleksei Aksimentiev,Zaida Luthey-Schulten,Laxmikant V. Kale,Klaus Schulten,Christophe Chipot,Emad Tajkhorshid +22 more
TL;DR: The main features of NAMD are reviewed, including the variety of options offered by NAMD for enhanced-sampling simulations aimed at determining free-energy differences of either alchemical or geometrical transformations and their applicability to specific problems.
Journal ArticleDOI
Natural triple excitations in local coupled cluster calculations with pair natural orbitals
TL;DR: The extension of the previously developed domain based local pair-natural orbital (DLPNO) based singles- and doubles coupled cluster ( DLPNO-CCSD) method to perturbatively include connected triple excitations is reported and the first CCSD(T) level calculation on an entire protein, Crambin with 644 atoms, and more than 6400 basis functions is demonstrated.
References
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Efficient, approximate and parallel Hartree–Fock and hybrid DFT calculations. A ‘chain-of-spheres’ algorithm for the Hartree–Fock exchange
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Calculation of solvent shifts on electronic g-tensors with the conductor-like screening model (COSMO) and its self-consistent generalization to real solvents (direct COSMO-RS).
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Prediction and interpretation of the 57Fe isomer shift in Mössbauer spectra by density functional theory
TL;DR: In this article, a linear correlation between non-relativistically calculated theoretical electron densities and experimentally measured ISs is established, and the calibration of two popular density functionals (B3LYP and BP86) for the prediction of isomer shifts (IS) in 57Fe Mossbauer (MB) spectra is reported.
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Efficient and accurate local approximations to coupled-electron pair approaches: An attempt to revive the pair natural orbital method
TL;DR: An efficient production level implementation of the closed shell CEPA and CPF methods is reported that can be applied to medium sized molecules and has essentially the same accuracy as parent CEPA (CPF) methods for thermochemistry, kinetics, weak interactions, and potential energy surfaces but is up to 500 times faster.