Car–Parrinello molecular dynamics

About: Car–Parrinello molecular dynamics is a research topic. Over the lifetime, 254 publications have been published within this topic receiving 17413 citations. The topic is also known as: CPMD.

Unified Approach for Molecular Dynamics and Density-Functional Theory

Abstract: 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 approximation, thereby making possible the simulation of both covalently bonded and metallic systems. In addition it permits the application of density-functional theory to much larger systems than previously feasible. The new technique is demonstrated by the calculation of some static and dynamic properties of crystalline silicon within a self-consistent pseudopotential framework.

Ab initio molecular dynamics simulation of liquid water: Comparison of three gradient‐corrected density functionals

Abstract: Three frequently used gradient‐corrected density functionals (B, BP, and BLYP) are applied in an ab initio molecular dynamics simulation of liquid water in order to evaluate their performance for the description of condensed aqueous systems. A comparison of structural characteristics (radial distribution functions) and dynamical properties (vibrational spectra, orientational relaxation, and self‐diffusion) leads to the conclusion that hydrogen bonding is too weak in the usual local density approximation corrected for exchange only according to Becke (B), whereas adding the gradient correction for correlation according to Perdew (BP) yields effective hydrogen bonds in the liquid that are too strong. The combination of B with the semilocal correlation functional according to Lee, Yang, and Parr (BLYP) yields the best agreement with experiment. The computational method, which is the basis for the determination of (adiabatic) electronic structure in the ab initio molecular dynamics simulation, has been valida...

Ab initio molecular dynamics: Propagating the density matrix with Gaussian orbitals

Abstract: We propose and implement an alternative approach to the original Car–Parrinello method where the density matrix elements (instead of the molecular orbitals) are propagated together with the nuclear degrees of freedom. Our new approach has the advantage of leading to an O(N) computational scheme in the large system limit. Our implementation is based on atom-centered Gaussian orbitals, which are especially suited to deal effectively with general molecular systems. The methodology is illustrated by applications to the three-body dissociation of triazine and to the dynamics of a cluster of a chloride ion with 25 water molecules.

Effective force fields for condensed phase systems from ab initio molecular dynamics simulation: a new method for force-matching.

Abstract: A novel least-squares fitting approach is presented to obtain classical force fields from trajectory and force databases produced by ab initio (e.g., Car–Parrinello) molecular dynamics (MD) simulations. The method was applied to derive effective nonpolarizable three-site force fields for liquid water at ambient conditions from Car–Parrinello MD simulations in the Becke–Lee–Yang–Parr approximation to the electronic density functional theory. The force-matching procedure includes a fit of short-ranged nonbonded forces, bonded forces, and atomic partial charges. The various parameterizations of the water force field differ by an enforced smooth cut-off applied to the short-ranged interaction term. These were obtained by fitting to the trajectory and force data produced by Car–Parrinello MD simulations of systems of 32 and 64 H2O molecules. The new water force fields were developed assuming both flexible or rigid molecular geometry. The simulated structural and self-diffusion properties of liquid water using ...

Trajectory Surface Hopping within Linear Response Time-Dependent Density-Functional Theory

Abstract: A fewest switches trajectory surface hopping algorithm based on linear response time-dependent density-functional theory is developed and implemented into the plane wave ab initio molecular dynamics package CPMD. A scheme to calculate nonadiabatic couplings using a multi determinantal approximation of the excited state wave function is introduced. The method is applied to the study of the photorelaxation of protonated formaldimine, a minimal model of the rhodopsin chromophore retinal. A good agreement of the structural and dynamic behavior is found with respect to state averaged multiconfiguration self consistent field based trajectory surface hopping.