First-principle calculations future application

In this review we have shown how investigations initially of the rupture of a covalent bond have led to the study of mechanically activated reactions and the influence of mechanical force on reaction pathways and rates of reaction. The application of mechanical force to control chemistry in a precise way is still in its infancy and we anticipate more activity in this direction in the future. The use of first principles calculations in understanding the rupture process is essential as a detailed description of the electronic structure is required for the correct description of covalent bond rupture. Calculations which determine the potential energy surface for stretching a small molecule in its ground state have evolved to consider the perturbation of a the potential surface of a molecule exposed to a constant force. First principles molecular dynamics simulations have enabled the study of bond rupture and experimental parameters which affect rupture. This determined that factors such as the length of the molecule in which the bond finds itself and the rate at which the molecule is stretched affect the... 

Polynuclear clusters fill the gap between mononuclear and extended solid transition metal vibronic systems. The applications of the theory of vibronic interaction allow to describe physical and chemical properties of these systems, sometimes directly linked to their application. The Jahn-Teller distortion found for the rhenium clusters defines the architecture of hybrid inorganic-organic materials and, as a result, their electric and magnetic properties. The application of the vibronic theory to the decatungstate cluster elucidates the details of its reactivity in the photocatalytic reaction. The modern DFT methods give a key to the calculations of key parameters of the vibronic theory. In future, we will assist at the combination of these methods with phenomenological approaches leading to the description of vibronic effects in physical and chemical properties of polynuclear clusters from first principles. 

In 1985, Car and Parrinello published a seminal article on an Unified approach for molecular dynamics and density functional theory Phys. Rev. Lett. 5S (1985) 2471). This paper established a basis for parameter-firee molecular dynamics simulations in which all the interactions are calculated on the fly via a first-principles quantum mechanical method. In the 15 years of its existence, the Car-Parrinello method has found widespread applications that expanded rapidly from physics to chemistry and, most recently, even into biology. In this article, the foundations of the method in its most common implementation, the one based on density functional theory, plane wave basis sets and pseudopotentials are described and extensions to the original scheme are outlined. The current power of Car-Parrinello simulations is illustrated by presenting selected case studies and possible future directions are sketched in the final outlook. 

Heterogeneous catalytic reactions in a class of Alumino-Silicates called zeolites, is an area which has recently been shown to be amenable to a variety of Quantum Chemistry calculations. The present review is a short introduction to this field, focusing on the problem of proton transfer, the primary process central to the acid-base chemistry exhibited in the nanopores of zeolite. This problem is closely related to the controversial question of zeolite acidity that has evoked great interest both experimentally and theoretically. Recent ab initio results are compared with experiments and some of the difficulties associated with the use of Quantum Chemistry are discussed. Finally the future of such ab initio calculations are questioned in view of the growing developments in the application of First-Principles molecular dynamics to the study of such systems. 

There have been books on droplet-related processes. However, the present book is probably the first one that encompasses the fundamental phenomena, principles and processes of discrete droplets of both normal liquids and melts. The author has attempted to correlate many diverse mechanisms and effects in a single and common framework in an effort to provide the reader with a new perspective of the identical basic physics and the inherent relationship between normal liquid and melt droplet processes. Another distinct and unique feature of this book is the comprehensive review of the empirical correlations, analytical and numerical models and computer simulations of droplet processes. These not only provide practical and handy approaches for engineering calculations, analyses and designs, but also form a useful basis for future in-depth research. Therefore, the present book covers the fundamental aspects of engineering applications and scientific research in the area. 

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