First-principle simulation

Alfe D and Gillan M J 1998 First-principles simulations of liquid Fe-S under Earth s core conditions Phys. Rev. B 58 8248-56... 

First-Principles Simulation of the Active Sites and Reaction Environment in Electrocatalysis... 

FIRST-PRINCIPLES SIMULATION OF THE ACTIVE SITES AND REACTION ENVIRONMENT... 

HaUey JW, Mazzolo A, Zhou Y, Price D. 1998. First-principles simulations of the electrode vertical har electrolyte interface. J Electroanal Chem 450 273-280. 

Schwegler, E. Grossman, J. C. Gygi, F. Galli, G., Towards an assessment of the accuracy of density functional theory for first principles simulations of water II, J. Chem. Phys. 2004,121, 5400-5409... 

The greatest limitation of QC methods is computational expense. This expense restricts system sizes to a few hundred atoms at most, and hence, it is not possible to examine highly elaborate systems with walls that are several atomic layers thick separated by several lubricant atoms or molecules. Furthermore, the expense of first-principles calculations imposes significant limitations on the time scales that can be examined in MD simulations, which may lead to shear rates that are orders of magnitude greater than those encountered in experiments. One should be aware of these inherent differences between first-principles simulations and experiments when interpreting calculated results. 

Predictions of high explosive detonation based on the new approach yield excellent results. A similar theory for ionic species model43 compares very well with MD simulations. Nevertheless, high explosive chemical equilibrium calculations that include ionization are beyond the current abilities of the Cheetah code, because of the presence of multiple minima in the free energy surface. Such calculations will require additional algorithmic developments. In addition, the possibility of partial ionization, suggested by first principles simulations of water discussed below, also needs to be added to the Cheetah code framework. 

Figure 8 The phase diagram of H20 as measured experimentally68 (black solid) and through first principles simulations of the superionic phase (gray dash).68,69 The estimated ZND state of HMX is shown as a square for reference.

The nature of the methanol-zeolite interaction has been shown to be sensitive to a number of parameters and as such has proved to be a good benchmark for judging the reliability of quantum chemical methods. Not only are there a number of possible modes whereby one and two molecules interact with an acidic site (245), the barrier to proton transfer is small and sensitive to calculation details. Recent first-principles simulations (236-238) suggest that the nature of adsorbed methanol may be sensitive to the topology of the zeolite pore. The activation and reaction of methane, ethane, and isobutane have been characterized by using reliable methods and models, and realistic activation energies for catalytic reactions have been obtained. 

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