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Quantum Chemistry Computer Programs
Quantum chemistry computer programs are used in computational chemistry to implement the methods of quantum chemistry. Most include the Hartree–Fock (HF) and some post-Hartree–Fock methods. They may also include density functional theory (DFT), molecular mechanics or semi-empirical quantum chemistry methods. The programs include both Open-source software, open source and commercial software. Most of them are large, often containing several separate programs, and have been developed over many years. Overview The following tables illustrates some of the main capabilities of notable packages: Numerical details Quantum chemistry and solid-state physics characteristics Post processing packages in quantum chemistry and solid-state physics See also Footnotes † "Academic": academic (no cost) license possible upon request; "Commercial": commercially distributed. ‡ Support for periodic systems (3d-crystals, 2d-slabs, 1d-rods and isolated molecules): 3d-periodic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computational Chemistry
Computational chemistry is a branch of chemistry that uses computer simulations to assist in solving chemical problems. It uses methods of theoretical chemistry incorporated into computer programs to calculate the structures and properties of molecules, groups of molecules, and solids. The importance of this subject stems from the fact that, with the exception of some relatively recent findings related to the hydrogen molecular ion (dihydrogen cation), achieving an accurate quantum mechanical depiction of chemical systems analytically, or in a closed form, is not feasible. The complexity inherent in the many-body problem exacerbates the challenge of providing detailed descriptions of quantum mechanical systems. While computational results normally complement information obtained by chemical experiments, it can occasionally predict unobserved chemical phenomena. Overview Computational chemistry differs from theoretical chemistry, which involves a mathematical description of chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CUDA
In computing, CUDA (Compute Unified Device Architecture) is a proprietary parallel computing platform and application programming interface (API) that allows software to use certain types of graphics processing units (GPUs) for accelerated general-purpose processing, an approach called general-purpose computing on GPUs. CUDA was created by Nvidia in 2006. When it was first introduced, the name was an acronym for ''Compute Unified Device Architecture'', but Nvidia later dropped the common use of the acronym and now rarely expands it. CUDA is a software layer that gives direct access to the GPU's virtual instruction set and parallel computational elements for the execution of compute kernels. In addition to drivers and runtime kernels, the CUDA platform includes compilers, libraries and developer tools to help programmers accelerate their applications. CUDA is designed to work with programming languages such as C, C++, Fortran, Python and Julia. This accessibility makes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CASTEP
CASTEP is a shared-source academic and commercial software package which uses density functional theory with a plane wave basis set to calculate the electronic properties of crystalline solids, surfaces, molecules, liquids and amorphous materials from first principles. CASTEP permits geometry optimisation and finite temperature molecular dynamics with implicit symmetry and geometry constraints, as well as calculation of a wide variety of derived properties of the electronic configuration. Although CASTEP was originally a serial, Fortran 77-based program, it was completely redesigned and rewritten from 1999 to 2001 using Fortran 95 and MPI for use on parallel computers by researchers at the Universities of York, Durham, St. Andrews, Cambridge and Rutherford Labs. History CASTEP was created in the late 1980s and early 1990s in the TCM Group of the Cavendish Laboratory in Cambridge. It was then an academic code written in Fortran77, and the name was originally derived from CAm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OpenACC
OpenACC (for ''open accelerators'') is a programming standard for parallel computing developed by Cray, CAPS, Nvidia and PGI. The standard is designed to simplify parallel programming of heterogeneous CPU/ GPU systems. As in OpenMP, the programmer can annotate C, C++ and Fortran source code to identify the areas that should be accelerated using compiler directives and additional functions. Like OpenMP 4.0 and newer, OpenACC can target both the CPU and GPU architectures and launch computational code on them. OpenACC members have worked as members of the OpenMP standard group to merge into OpenMP specification to create a common specification which extends OpenMP to support accelerators in a future release of OpenMP. These efforts resulted in a technical report for comment and discussion timed to include the annual Supercomputing Conference (November 2012, Salt Lake City) and to address non-Nvidia accelerator support with input from hardware vendors who participate in Ope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CASINO
A casino is a facility for gambling. Casinos are often built near or combined with hotels, resorts, restaurants, retail shops, cruise ships, and other tourist attractions. Some casinos also host live entertainment, such as stand-up comedy, concerts, and sports. Etymology and usage ''Casino'' is of Italian language, Italian origin; the root means a house. The term ''casino'' may mean a small country villa, Summerhouse (building), summerhouse, or social club. During the 19th century, ''casino'' came to include other public buildings where pleasurable activities took place; such edifices were usually built on the grounds of a larger Italian villa or palazzo, and were used to host civic town functions, including dancing, gambling, music listening, and sports. Examples in Italy include Villa Farnese and Villa Giulia, and in the US the Newport Casino in Newport, Rhode Island. In modern-day Italian, a is a brothel (also called , literally "closed house"), a mess (confusing situation), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CADPAC
CADPAC, the Cambridge Analytic Derivatives Package, is a suite of programs for ab initio computational chemistry calculations. It has been developed by R. D. Amos with contributions from I. L. Alberts, J. S. Andrews, S. M. Colwell, N. C. Handy, D. Jayatilaka, P. J. Knowles, R. Kobayashi, K. E. Laidig, G. Laming, A. M. Lee, P. E. Maslen, C. W. Murray, J. E. Rice, E. D. Simandiras, A. J. Stone, M.-D. Su and D. J. Tozer. at the University of Cambridge since 1981. It is capable of molecular Hartree–Fock calculations, Møller–Plesset calculations, various other correlated calculations and density functional theory calculations. See also * Quantum chemistry computer programs Quantum chemistry computer programs are used in computational chemistry to implement the methods of quantum chemistry. Most include the Hartree–Fock (HF) and some post-Hartree–Fock methods. They may also include density functional theory (DFT) ... External links * Computational chemistry softw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BigDFT
BigDFT is a free software package for physicists and chemists, distributed under the GNU General Public License, whose main program allows the total energy, charge density, and electronic structure of systems made of electrons and nuclei (molecules and periodic/crystalline solids) to be calculated within density functional theory (DFT), using pseudopotentials, and a wavelet basis. Overview BigDFT implements density functional theory (DFT) by solving the Kohn–Sham equations describing the electrons in a material, expanded in a Daubechies wavelet basis set and using a self-consistent direct minimization or Davidson diagonalisation methods to determine the energy minimum. Computational efficiency is achieved through the use of fast short convolutions and pseudopotentials to describe core electrons. In addition to total energy, forces and stresses are also calculated so that geometry optimizations and ab initio molecular dynamics may be carried out. The Daubechies wavelet b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Python (programming Language)
Python is a high-level programming language, high-level, general-purpose programming language. Its design philosophy emphasizes code readability with the use of significant indentation. Python is type system#DYNAMIC, dynamically type-checked and garbage collection (computer science), garbage-collected. It supports multiple programming paradigms, including structured programming, structured (particularly procedural programming, procedural), object-oriented and functional programming. It is often described as a "batteries included" language due to its comprehensive standard library. Guido van Rossum began working on Python in the late 1980s as a successor to the ABC (programming language), ABC programming language, and he first released it in 1991 as Python 0.9.0. Python 2.0 was released in 2000. Python 3.0, released in 2008, was a major revision not completely backward-compatible with earlier versions. Python 2.7.18, released in 2020, was the last release of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomistix ToolKit
QuantumATK (formerly Atomistix ToolKit or ATK) is a commercial software for atomic-scale modeling and simulation of nanosystems. The software was originally developed by Atomistix A/S, and was later acquired by QuantumWise following the Atomistix bankruptcy. QuantumWise was then acquired by Synopsys in 2017. Atomistix ToolKit is a further development of TranSIESTA-C, which in turn in based on the technology, models, and algorithms developed in the academic codes TranSIESTA, and McDCal, employing localized basis sets as developed in SIESTA. Features Atomistix ToolKit combines density functional theory with non-equilibrium Green's functions for first principles electronic structure and transport calculations of *electrode—nanostructure—electrode systems (two-probe systems) *molecules *periodic systems (bulk crystals and nanotubes) The key features are *Calculation of transport properties of two-probe systems under an applied bias voltage *Calculation of energy sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AMPAC
AMPAC is a general-purpose semiempirical quantum chemistry program. It is marketed by Semichem, Inc. and was developed originally by Michael Dewar and his group. The first version of AMPAC (2.1) was made available in 1985 through the Quantum Chemistry Program Exchange (QCPE). Subsequent versions were released through the same source, representing minor updates and optimized versions for other platforms. In 1992, Semichem, Inc. was formed at Professor Dewar's urging to maintain and market the program. ''AMPAC 4.0 with Graphical User Interface'' was released in August of that year. Semichem's current version of AMPAC is 10.http://www.semichem.com/ AMPAC current implements the SAM1, AM1, MNDO, MNDO/d, PM3, MNDOC MINDO/3, RM1 and PM6 semi-empirical methods and AMSOL and COSMO salvation models. See also * Quantum chemistry computer programs Quantum chemistry computer programs are used in computational chemistry to implement the methods of quantum chemistry. Most include the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amsterdam Density Functional
Amsterdam Density Functional (ADF) is a program for first-principles electronic structure calculations that makes use of density functional theory (DFT). ADF was first developed in the early seventies by the group of E. J. Baerends from the Vrije Universiteit in Amsterdam, and by the group of T. Ziegler from the University of Calgary. Nowadays many other academic groups are contributing to the software. Software for Chemistry & Materials (SCM), formerly known as Scientific Computing & Modelling is a spin-off company from the Baerends group. SCM has been coordinating the development and distribution of ADF since 1995. Together with the rise in popularity of DFT in the nineties, ADF has become a popular computational chemistry software package used in the industrial and academic research. ADF excels in spectroscopy, transition metals, and heavy elements problems. A periodic structure counterpart of ADF named BAND is available to study bulk crystals, polymers, and surfaces. The Amste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
