Carr-Parrinello molecular dynamics

CARS CAT CCD CIF CPMD CT CTAB CW Coherent Anti-Stokes Raman Scattering Computerized Axial Tomography Charge-Coupled Device Chemical Image Fusion Carr-Parrinello Molecular Dynamics Computed Tomography Cetyltrimethylammonium Bromide Continuous Wave (Laser)... 

The calculations are performed within the framework of the Carr-Parrinello molecular dynamics [25, 26]. Our approach is based on the density functional theory with generalized gradient approximations after Becke for the exchange energy [27] and Lee, Yang, and Parr for the correlation energy [28]. Troullier-Martins type... 

K) with molecular dynamics (which are dynamic and involve a finite temperature). These methods come under the name of ab initio molecular dynamics or Carr-Parrinello molecular dynamics, and in principle give access to all the finite-temperature information one might be interested in by combining the methods of quantum chemistry and statistical mechanics. These methods are state-of-the-art and are still restricted to very small system sizes, but hold great promise for the future. 

Carre, A., Horbach, J., Ispas, S., and Kob, W. (2008) New fitting scheme to obtain effective potential from Car-Parrinello molecular-dynamics simulations application to sihca, Eur. Lett., 82,17001. 

We wish to end this section by saying that now it is possible to perform molecular dynamics simulations on the fly without precomputing the potential energy surface. This idea was introduced by Carr and Parrinello344-345, and is known as the Carr-Parrinello dynamics. In this approach the nuclear motions are treated classically within the molecular dynamics method, but the energy and force are precomputed for each configuration of the nuclei with a suitable version of... 

CarR, Parrinello M (1985) Unified approach for molecular dynamics and density-functional theory, Phys. Rev. Lett. 55 2471-2474... 

R. Carr and M. Parrinello, Phys. Rev. Lett., 55,2471 (1985). Unified Approach for Molecular Dynamics and Density-Functional Theory. 

One very prominent development in DFT has been the coupling of electronic structure calculations (which, when the ground state is concerned, apply to zero temperature) with finite-temperature molecular dynamics simulations. The founding paper in this field was published by Carr and Parrinello in 1985 [13]. Carr and Parrinello formulate effective equations of motion for the electrons to be solved simultaneously with the classical equations of motion for the ions. The forces on the ions are calculated from first principles by use of the Hellman-Feynman theorem. An alternative to the Carr-Parrinello method is to solve the electronic structure self-consistently at every ionic time step. Both methods are referred to as ab initio molecular dynamics (AIMD) [14]. 

In the present article, we report a study concerning the reaction mechanism of a prototype reaction using both static and dynamic approaches to explore a DFT potential surface. The static approach is the standard IRC model, while the dynamic one is based on a Carr-Parrinello method performed with localized (Gaussian) orbitals, the so-called atom-centered density matrix propagation (ADMP) model.25 Our aim is to elucidate the differences, and the common aspects, between the two approaches in the analysis of bond breaking/formation. To this end, we have chosen topological quantities as probe molecular descriptors. 

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