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Materias / palabras clave: Tecnología; Desarrollo científico; Desarrollo tecnológico; Ciencia; Física; Química; Bioquímica; Biología molecular; Nanotechnology; Technology; Social aspects; Science; Physics; Chemistry; Biochemistry; Molecular...

In molecular dynamics (MD) simulations the need often arises to maintain such parameters as temperature or pressure rather than energy and volume, or to impose gradients for studying transport properties in nonequilibriu...

Materias / palabras clave: Spectral line; Molecular spectroscopy; Diatomic molecule; Molecule; Chemistry; Physics; Astronomy; Organic chemistry

A molecular dynamics simulation method which can generate configurations belonging to the canonical (T, V, N) ensemble or the constant temperature constant pressure (T, P, N) ensemble, is proposed. The physical system of...

We present ab initio quantum-mechanical molecular-dynamics simulations of the liquid-metal--amorphous-semiconductor transition in Ge. Our simulations are based on (a) finite-temperature density-functional theory of the o...

Correlation consistent and augmented correlation consistent basis sets have been determined for the second row atoms aluminum through argon. The methodology, originally developed for the first row atoms [T. H. Dunning, J...

A new implementation of the conductor-like screening solvation model (COSMO) in the GAUSSIAN94 package is presented. It allows Hartree−Fock (HF), density functional (DF) and post-HF energy, and HF and DF gradient calcu...

A new direct difference method for the computation of molecular interactions has been based on a bivariational transcorrelated treatment, together with special methods for the balancing of other errors. It appears that t...

Materias / palabras clave: Chemistry; Dielectric; Ab initio; Electric field; Polarization (electrochemistry); Electrostatics; Wave function; Ab initio quantum chemistry methods; Chemical physics; Solvent; Solvent effects; Molecular physics

Ab initio effective core potentials (ECP’s) have been generated to replace the innermost core electron for third-row (K–Au), fourth-row (Rb–Ag), and fifth-row (Cs–Au) atoms. The outermost core orbitals—correspo...

We present ab initio quantum-mechanical molecular-dynamics calculations based on the calculation of the electronic ground state and of the Hellmann-Feynman forces in the local-density approximation at each molecular-dyna...

Abstract CHARMM ( C hemistry at HAR vard M acromolecular M echanics) is a highly flexible computer program which uses empirical energy functions to model macromolecular systems. The program can read or model build struct...

Three recently proposed constant temperature molecular dynamics methods by: (i) Nosé (Mol. Phys., to be published); (ii) Hoover et al. [Phys. Rev. Lett. 48, 1818 (1982)], and Evans and Morriss [Chem. Phys. 77, 63 (1983)...

New protein parameters are reported for the all-atom empirical energy function in the CHARMM program. The parameter evaluation was based on a self-consistent approach designed to achieve a balance between the internal (b...

CHARMM (Chemistry at HARvard Molecular Mechanics) is a highly versatile and widely used molecular simulation program. It has been developed over the last three decades with a primary focus on molecules of biological inte...

Contracted Gaussian basis sets for molecular calculations are derived from uncontracted (12,8) and (12,9) sets for the neutral second row atoms, Z=11–18, and for the negative ions P−, S−, and Cl−. Calculations on...

Molecular simulation is an extremely useful, but computationally very expensive tool for studies of chemical and biomolecular systems. Here, we present a new implementation of our molecular simulation toolkit GROMACS whi...

In the past, basis sets for use in correlated molecular calculations have largely been taken from single configuration calculations. Recently, Almlöf, Taylor, and co-workers have found that basis sets of natural orbital...

Adequate initial configurations for molecular dynamics simulations consist of arrangements of molecules distributed in space in such a way to approximately represent the system's overall structure. In order that the simu...

A new Lagrangian formulation is introduced. It can be used to make molecular dynamics (MD) calculations on systems under the most general, externally applied, conditions of stress. In this formulation the MD cell shape a...

An extended basis set of atomic functions expressed as fixed linear combinations of Gaussian functions is presented for hydrogen and the first-row atoms carbon to fluorine. In this set, described as 4–31 G, each inner ...

We present a unified scheme that, by combining molecular dynamics and density-functional theory, profoundly extends the range of both concepts. Our approach extends molecular dynamics beyond the usual pair-potential appr...

Ab initio effective core potentials (ECP’s) have been generated to replace the Coulomb, exchange, and core-orthogonality effects of the chemically inert core electron in the transition metal atoms Sc to Hg. For the sec...

Materias / palabras clave: Parallel computing; Computer science; Benchmark (surveying); Parallel algorithm; Intel iPSC; Algorithm; Range (aeronautics); Molecular dynamics; Supercomputer; Node (physics); Computational science; Physics