|
Quantemol
Quantemol Ltd is based in University College London initiated by Professor Jonathan Tennyson (physicist), Jonathan Tennyson FRS and Dr. Daniel Brown in 2004. The company initially developed a unique software tool, #Quantemol-N, Quantemol-N, which provides full accessibility to the highly sophisticated UK molecular R-matrix codes, used to model electron polyatomic molecule interactions. Since then Quantemol has widened to further types of simulation, with Plasma (physics), plasmas and industrial plasma tools, in #Quantemol-VT, Quantemol-VT in 2013 and launched in 2016 a sustainable database #Quantemol-DB, Quantemol-DB, representing the chemical and radiative transport properties of a wide range of plasmas. Quantemol-N The Quantemol-N software system has been developed to simplify use of UK Molecular R-matrix Codes, UK R-matrix codes. It provides an interface for non specialists to perform ab initio electron-molecule scattering calculations. Quantemol-N calculates a variety of ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University College London
, mottoeng = Let all come who by merit deserve the most reward , established = , type = Public research university , endowment = £143 million (2020) , budget = £1.544 billion (2019/20) , chancellor = Anne, Princess Royal(as Chancellor of the University of London) , provost = Michael Spence , head_label = Chair of the council , head = Victor L. L. Chu , free_label = Visitor , free = Sir Geoffrey Vos , academic_staff = 9,100 (2020/21) , administrative_staff = 5,855 (2020/21) , students = () , undergrad = () , postgrad = () , coordinates = , campus = Urban , city = London, England , affiliations = , colours = Purple and blue celeste , nickname ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transition State Theory
In chemistry, transition state theory (TST) explains the reaction rates of elementary chemical reactions. The theory assumes a special type of chemical equilibrium (quasi-equilibrium) between reactants and activated transition state complexes. TST is used primarily to understand qualitatively how chemical reactions take place. TST has been less successful in its original goal of calculating absolute reaction rate constants because the calculation of absolute reaction rates requires precise knowledge of potential energy surfaces, but it has been successful in calculating the standard enthalpy of activation (Δ''H''‡, also written Δ‡''H''ɵ), the standard entropy of activation (Δ''S''‡ or Δ‡''S''ɵ), and the standard Gibbs energy of activation (Δ''G''‡ or Δ‡''G''ɵ) for a particular reaction if its rate constant has been experimentally determined. (The ‡ notation refers to the value of interest ''at the transition state''; Δ''H''‡ is the difference between the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Q-Chem
Q-Chem is a general-purpose electronic structure package featuring a variety of established and new methods implemented using innovative algorithms that enable fast calculations of large systems on various computer architectures, from laptops and regular lab workstations to midsize clusters and HPCC, using density functional and wave-function based approaches. It offers an integrated graphical interface and input generator; a large selection of functionals and correlation methods, including methods for electronically excited states and open-shell systems; solvation models; and wave-function analysis tools. In addition to serving the computational chemistry community, Q-Chem also provides a versatile code development platform. History Q-Chem software is maintained and distributed by Q-Chem, Inc., located in Pleasanton, California, USA. It was founded in 1993 as a result of disagreements within the Gaussian company that led to the departure (and subsequent "banning") of John Pople ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PSI (computational Chemistry)
Psi is an ab initio computational chemistry package originally written by the research group of Henry F. Schaefer, III (University of Georgia). Utilizing Psi, one can perform a calculation on a molecular system with various kinds of methods such as Hartree-Fock, Post-Hartree–Fock electron correlation methods, and Density functional theory. The program can compute energies, optimize molecular geometries, and compute vibrational frequencies. The major part of the program is written in C++, while Python API is also available, which allows users to perform complex computations or automate tasks easily. Psi4 is the latest release of the program package - it is open source, released as free under the GPL through GitHub. Primary development of Psi4 is currently performed by the research groups of David Sherrill (Georgia Tech), T. Daniel Crawford (Virginia Tech), Francesco Evangelista (Emory University), and Henry F. Schaefer, III (University of Georgia), with substantial contribu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PQS (chemical)
PQS is a general purpose quantum chemistry program. Its roots go back to the first ab initio gradient program developed in Professor Peter Pulay's group but now it is developed and distributed commercially by Parallel Quantum Solutions. There is a reduction in cost for academic users and a site license. Its strong points are geometry optimization, NMR chemical shift calculations, and large MP2 calculations, and high parallel efficiency on computing clusters. It includes many other capabilities including Density functional theory, the semiempirical methods, MINDO/3, MNDO, AM1 and PM3, Molecular mechanics using the SYBYL 5.0 Force Field, the quantum mechanics/molecular mechanics mixed method using the ONIOM method, natural bond orbital (NBO) analysis and COSMO solvation models. Recently, a highly efficient parallel CCSD(T) code for closed shell systems has been developed. This code includes many other post Hartree–Fock methods: MP2, MP3, MP4, CISD, CEPA, QCISD and so o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NWChem
NWChem is an ab initio computational chemistry software package which includes quantum chemical and molecular dynamics functionality. It was designed to run on high-performance parallel supercomputers as well as conventional workstation clusters. It aims to be scalable both in its ability to treat large problems efficiently, and in its usage of available parallel computing resources. NWChem has been developed by the Molecular Sciences Software group of the Theory, Modeling & Simulation program of the Environmental Molecular Sciences Laboratory (EMSL) at the Pacific Northwest National Laboratory (PNNL). The early implementation was funded by the EMSL Construction Project. NWChem is currently being redesigned and reimplemented for exascale computing platforms (NWChemEx ). Capabilities * Molecular mechanics * Molecular dynamics * Hartree–Fock (self-consistent field method) * Density functional theory * Time-dependent density functional theory * Post-Hartree–Fock me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPQC
MPQC (Massively Parallel Quantum Chemistry) is an ab initio computational chemistry software program. Three features distinguish it from other quantum chemistry programs such as Gaussian and GAMESS: it is open-source, has an object-oriented design, and is created from the beginning as a parallel processing program. It is available in Ubuntu and Debian. MPQC provides implementations for a number of important methods for calculating electronic structure, including Hartree–Fock, Møller–Plesset perturbation theory (including its explicitly correlated linear R12 versions), and density functional theory. See also * List of quantum chemistry and solid state physics software 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 ... References External links MPQC Homepage {{Che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOLCAS
MOLCAS is an ab initio computational chemistry program, developed as a joint project by a number of international institutes. MOLCAS is developed by scientists to be used by scientists. It is not primarily a commercial product and it is not sold in order to produce a fortune for its owner (the Lund University). Focus in the program is placed on methods for calculating general electronic structures in both ground and excited states. MOLCAS contains codes for general and effective multiconfigurational SCF calculations at the Complete Active Space (CASSCF) level, but also employing more restricted MCSCF wave functions (RASSCF). It is also possible, at this level of theory, to optimize geometries for equilibrium and transition states using gradient techniques and to compute force fields and vibrational energies. MOLCAS also contains second order perturbation theory codes CASPT2 and RASPT2. History MOLCAS code has been created at the late 1980s by the group of Prof. Björn O. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaussian (software)
Gaussian is a general purpose computational chemistry software package initially released in 1970 by John Pople and his research group at Carnegie Mellon University as Gaussian 70. It has been continuously updated since then. The name originates from Pople's use of Gaussian orbitals to speed up molecular electronic structure calculations as opposed to using Slater-type orbitals, a choice made to improve performance on the limited computing capacities of then-current computer hardware for Hartree–Fock calculations. The current version of the program is Gaussian 16. Originally available through the Quantum Chemistry Program Exchange, it was later licensed out of Carnegie Mellon University, and since 1987 has been developed and licensed by Gaussian, Inc. Standard abilities According to the most recent Gaussian manual, the package can do: *Molecular mechanics **AMBER **Universal force field (UFF) **DREIDING force field *Semi-empirical quantum chemistry method calculations **Austin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GAMESS
GAMESS is a computational chemistry software program and stands for General Atomic and Molecular Electronic Structure System. The original Quantum Chemistry Program Exchange (QCPE) code of GAMESS split in 1981 and now the three version differ considerably: * GAMESS (UK), a fork of the General Atomic and Molecular Electronic Structure System computational chemistry software program * GAMESS (US), a fork of the General Atomic and Molecular Electronic Structure System computational chemistry software program * Firefly (computer program) Firefly, formerly named PC GAMESS, is an ab initio computational chemistry program for Intel-compatible x86, x86-64 processors based on GAMESS (US) sources. However, it has been mostly rewritten (60-70% of the code), especially in platform-spe ... or PC GAMESS, an ab initio computational chemistry program based on GAMESS (US) sources Computational chemistry software {{chem-software-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CP2K
CP2K is a freely available (GPL) quantum chemistry and solid state physics program package, written in Fortran 2008, to perform atomistic simulations of solid state, liquid, molecular, periodic, material, crystal, and biological systems. It provides a general framework for different methods: density functional theory (DFT) using a mixed Gaussian and plane waves approach (GPW) via LDA, GGA, MP2, or RPA levels of theory, classical pair and many-body potentials, semi-empirical ( AM1, PM3, MNDO, MNDOd, PM6) and tight-binding Hamiltonians, as well as Quantum Mechanics/Molecular Mechanics (QM/MM) hybrid schemes relying on the Gaussian Expansion of the Electrostatic Potential (GEEP). The Gaussian and Augmented Plane Waves method (GAPW) as an extension of the GPW method allows for all-electron calculations. CP2K can do simulations of molecular dynamics, metadynamics, Monte Carlo, Ehrenfest dynamics, vibrational analysis, core level spectroscopy, energy minimization, and transition sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxwellian Distribution
* Maxwell–Boltzmann distribution * The Maxwellians ''The Maxwellians'' is a book by Bruce J. Hunt, published in 1991 by Cornell University Press; a paperback edition appeared in 1994, and the book was reissued in 2005. It chronicles the development of electromagnetic theory in the years after the ... (1991 book) See also * List of things named after James Clerk Maxwell {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
