Theoretical Chemistry Accounts: Theory

Theoretical Chemistry Accounts Theory, Computation, and Modeling (formerly... 

A. Trautwein, R. Zimmermann and F. Harris, Theoretical Chemistry Accounts Theory, Computation, and Modeline, Theor. Chim. Acta, 1975, 37, 89-104. 

Ridley, J. E., 8c Zerner, M. C. (1973). Intermediate neglect of differential overlap techniques for spectroscopy pyrrole and the azines. Theoretical Chemistry Accounts Theory, Computation, and Modeling, 32,111-134. 

Keal, T., Wanko, M., Thiel, W. (2009). Assessment of semiempirical methods for the photoisomerisation of a protonated Schiff base. Theoretical Chemistry Accounts Theory, Computation, and Modeling (Theoretica Chimica Acta), 123(1), 145-156. 

Theory a relativistic electrons-only theory for chemistry. Theoretical Chemistry Accounts, 116, 241-252 and references therein. 

Wang, F. and Li, L. (2002) A singularity excluded approximate expansion scheme in relativistic density functional theory. Theoretical Chemistry Accounts, 108, 53-60. 

Arno, M., Domingo, L. R. Density functional theory study of the mechanism of the proline-catalyzed intermolecular aldol reaction. Theoretical Chemistry Accounts 2002,108, 232-239. 

Calvo-Losada, S., Sordo, T. L., Lopez-Herrera, F. J., Quirante, J. J. The influence of protecting the hydroxyl group of P-oxy-a-diazo carbonyl compounds in the competition between Wolff rearrangement and [1,2]-hydrogen shift. Density functional theory study and topological analysis of the charge density. Theoretical Chemistry Accounts 2000,103,423-430. 

Chandler, D. 2005. Interfaces and the driving force of hydrophobic assembly. Nature. 437,640. Chapman, D. L. 1913. A contribution to the theory of electrocapillarity. LI. The London, Edinburgh, and Dublin Philisophical Magazine and Journal of Science. 25, 475. Cheatham, T. E. and B. R. Brooks. 1998. Recent advances in molecular dynamics simulation toward the realistic representation of biomolecules in solution. Theoretical Chemistry Accounts. 99, 279. 

Bredow, T., Jug, K. (2005). Theory and range of modern semiempirical molecular orbital methods. Theoretical Chemistry Accounts, 113,1. 

Sironi, M., Genoni, A., Civera, M., Pieraccini, S., Ghitti, M. (2007). Extremely localized molecular orbitals Theory and applications. Theoretical Chemistry Accounts, 117, 685. 

Hattig, C., Jorgensen, P. (1998). Dispersion coefficients for first hyperpolarizabilities using coupled cluster quadratic response theory. Theoretical Chemistry Accounts, 100, 230. 

Kinetics on the level of individual molecules is often referred to as reaction dynamics. Subtle details are taken into account, such as the effect of the orientation of molecules in a collision that may result in a reaction, and the distribution of energy over a molecule s various degrees of freedom. This is the fundamental level of study needed if we want to link reactivity to quantum mechanics, which is really what rules the game at this fundamental level. This is the domain of molecular beam experiments, laser spectroscopy, ah initio theoretical chemistry and transition state theory. It is at this level that we can learn what determines whether a chemical reaction is feasible. 

The development of theoretical chemistry ceased at about 1930. The last significant contributions came from the first of the modern theoretical physicists, who have long since lost interest in the subject. It is not uncommon today, to hear prominent chemists explain how chemistry is an experimental science, adequately practiced without any need of quantum mechanics or the theories of relativity. Chemical thermodynamics is routinely rehashed in the terminology and concepts of the late nineteenth century. The formulation of chemical reaction and kinetic theories take scant account of statistical mechanics and non-equilibrium thermodynamics. Theories of molecular structure are entirely classical and molecular cohesion is commonly analyzed in terms of isolated bonds. Holistic effects and emergent properties that could... 

For general accounts see W. H. Brock, The Fontana History of Chemistry (London Fontana Press, 1992), 508-569, and references therein M.J. Nye, From Chemical Philosophy to Theoretical Chemistry. Dynamics of Matter and Dynamics of Disciplines (Berkeley University of California Press, 1993), 139-223 R. E. Kohler, The Lewis-Lang-muir theory of valence and the chemical... 

The most conspicuous failure of quantum physics, as a theory of chemistry, is the demonstrated inability to account in detail for the observed periodic order of the elements, the single most important feature of theoretical chemistry. The importance of this failure, if not completely ignored, is routinely underplayed in elementary chemistry texts, by statements such as [61] ... 

We quote a few review papers from our group (Tomasi et al., 1991 Bonaccorsi et al., 1984a Alagona et al., 1986) giving a fuller account of this procedure. The problem of getting a rationale of the chemical effects that can be reduced to interactions among molecular subunits is of basic importance in theoretical chemistry, and several other authors have proposed some models and theories addressed for this aim. Since they have some points in common with our approach, they are referred to in the above quoted review papers. 

Relativistic and electron correlation effects play an important role in the electronic structure of molecules containing heavy elements (main group elements, transition metals, lanthanide and actinide complexes). It is therefore mandatory to account for them in quantum mechanical methods used in theoretical chemistry, when investigating for instance the properties of heavy atoms and molecules in their excited electronic states. In this chapter we introduce the present state-of-the-art ab initio spin-orbit configuration interaction methods for relativistic electronic structure calculations. These include the various types of relativistic effective core potentials in the scalar relativistic approximation, and several methods to treat electron correlation effects and spin-orbit coupling. We discuss a selection of recent applications on the spectroscopy of gas-phase molecules and on embedded molecules in a crystal enviromnent to outline the degree of maturity of quantum chemistry methods. This also illustrates the necessity for a strong interplay between theory and experiment. 

The general treatment of the theory of chemical reactions presented in this book is based on the usual adiabatic separation of nuclear and electronic motions which permits a definition of the potential energy as a function of internuclear distances This approach proves to be very useful for the study of electronically adiabatic reactions, provided a separation of the rotation of the reacting system, treated as a supermolecule, is possible. In general, such a separation seems to be a bad approximation /10/. A consideration of the coupling of the overall rotation with the internal motions of the system means taking into account the possibility of non-adiabatic transitions from one to another potential energy surface. This is still an unsolved problem of theoretical chemistry which is open for discussion. 

Useful atomic and subatomic scale information on hydroxylated oxide surfaces and their interaction with aggressive ions (e.g., Cl ) can be provided by theoretical chemistry, whose application to corrosion-related issues has been developed in the context of the metal/liquid interfaces [34 9]. The application of ah initio density functional theory (DFT) and other atomistic methods to the problem of passivity breakdown is, however, limited by the complexity of the systems that must include three phases, metal(alloy)/oxide/electrolyte, then-interfaces, electric field, and temperature effects for a realistic description. Besides, the description of the oxide layer must take into account its orientation, the presence of surface defects and bulk point defects, and that of nanostructural defects that are key actors for the reactivity. Nevertheless, these methods can be applied to test mechanistic hypotheses. 

Onsager, Lars (1903-76) Norwegian-born American chemist. Onsager made several important contributions to theoretical chemistry and physics. In 1926 he improved on the Debye-Hiickel theory of electrolytes by taking the Brownian motion of ions into account. He subsequently investigated the dielectric constants of matter that contains polar molecules. In 1931 he published fundamental work on nonequilibrium thermodynamics. He was awarded the 1968 Nobel Prize for chemistry for this work. 

Let us look into a little more detailed aspects of the cmrent and future perspective for chemical d3mamics. As noted above, the foimdations of theoretical chemistry were already established in the 1920 s (both the papers of Born-Oppenheimer and Heitler London were published in 1927) and 1930 s (Landau and Zener published in 1932, and the transition state theory of Eyring and Evans-Polan3d was almost simultaneously launched in 1935), and even today the basic framework remains essentially the same. However, there are many reasons we need to promote the electronic-state theory into the realm of d3mamical electron theory by taking explicit account of time t in it. Below are listed some of the current attempts to achieve this goal. 

The principal notions and conceptual systems of theoretical organic chemistry have been evolved from generalizations and rationalizations of the results of research into reaction mechanisms. In the sixties the data from quantum mechanical calculations began to be widely invoked to account for and predict the reactivity of organic compounds. In addition to and in place of the notions derived on the basis of the resonance and mesomerism theories that earlier had been treated semiquantitatively by means of correlation equations, novel research tools came to be employed such as reactivity indices, perturbation MO theory, or the Woodward-Hoffmann rules. It is very characteristic of these approaches, which have now taken firm root in the field of theoretical chemistry, that they, on the whole, imply an a priori assumption of the mechanism and probable structures of the transition states of reactions. 

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