Fundamental perspective

The fundamental perspective of this review is that simulation results are not absolute, but rather are intrinsically accompanied by statistical uncertainty [4-8]. Although this view is not novel, it is at odds with informal statements that a simulation is "converged." Beyond quantification of uncertainty for specific observables, we also advocate quantification of overall sampling quality in terms of the "effective sample size" [8] of an equilibrium ensemble [9,10]. 

Throughout this chapter we have dealt with surface tension from a phenomenological point of view almost exclusively. From fundamental perspective, however, descriptions from a molecular perspective are often more illuminating than descriptions of phenomena alone. In condensed phases, in which interactions involve many molecules, rigorous derivations based on the cumulative behavior of individual molecules are extremely difficult. We shall not attempt to review any of the efforts directed along these lines for surface tension. Instead, we consider the various types of intermolecular forces that exist and interpret 7 for any interface as the summation of contributions arising from the various types of interactions that operate in the materials forming the interface. 

The competition between molecular-based and molecule-substrate interactions is one of the features that make supramolecular assemblies based on the combination of molecular components and solid substrates so exciting and also potentially useful from the applications point of view. The control issue is whether can one achieve long-lived charge separation between molecular components when immobilized on a surface, and from the fundamental perspective, can the interactions between the surface and molecular components be manipulated In this section, the immobilization of molecular components consisting of at least two electroactive and/or photoactive units will be discussed. The intramolecular interactions within these dyads in solution, as well as their behavior as interfacial supramolecular triads when immobilized on nanocrystalline TiC>2, will be compared. 

Tachibana A (2002) Field Energy Density In Chemical Reaction Systems. In Brandas EJ, Kryachko ES (eds) Fundamental Perspectives in Quantum Chemistry, A Tribute to the Memory of Per-Olov Lowdin, Vol. 2, Kluwer Academic Publishers, Dordrecht, pp 211-239... 

For CSD processing of ferroelectric thin films, a homogeneous solution of the necessary cation species that may later be applied to a substrate must be prepared. Overall, the basic process involves the steps of solution preparation, film deposition, pyrolysis for removal of organic constituents, and heat treatment to induce crystallization, as shown in Figure 27.2. This section provides some of the experimental details associated with the CSD process, while the next section discusses the process from a more fundamental perspective. 

Comparison of the properties of CSD thin films to the analogous bulk material properties has also received great attention because of the need for high dielectric constant materials for DRAM applications.Basceri et ai 134,135 jj yg thoroughly considered the differences between film and bulk properties from a fundamental perspective and have been able to interpret these differences in terms of stresses present in the films, compositional differences, and the impact of these characteristics on the phenomenological behavior of the material as predicted from a Landau-Ginzburg-Devonshire approach. All observed differences between film and bulk properties were explainable using this approach. 

Nanotubes in the laboratory often exhibit an aspect ratio of 10 000, i.e., length L approximately in microns. From the fundamental perspective, an important stimulus of this research is the realization that such a linear geometry provided by small R nanotubes yields one-dimensional (ID) phases of matter that description is certainly true from the phase transition perspective (since only one dimension approaches infinity in the thermodynamic limit). The subject of ID matter has been studied as an academic problem for many years [17, 18]. An intriguing aspect of the subject is that no phase transitions occur in a strictly ID system at finite temperature (T). In the nanotube environment, however, ID lines of adsorbed molecules can interact with neighboring lines of molecules, resulting in a 3D transition at finite T. To this date, in fact, predictions have been made of ID, 2D, 3D, and even 4D phases of matter in this novel environment [19, 20]. All such regimes will be discussed, to some extent, in this chapter and Chapter 15. The rich variety of phenomena has made theoretical study both enjoyable and rewarding. 

As the experimental and theoretical investigations of gas adsorption on carbon nanotubes progressed, a number of questions that are important from a fundamental perspective have emerged. These questions provide an independent scientific motivation for the study of adsorption of various gases on these novel carbon materials. 

From a fundamental perspective the Joulc -Thotnson effect is important because it can be linked directly to the nature of intermolecular forces between gas molecules [205]. Consider, for example, a classic ideal gas as the simplest case in which molecules do not interact by definition. For this model it is simple to show that as a consequence of the absence of any intermolecular interactions a Joule-Thomson effect does not exist, that is, <5 = 0 [200, 201]. If, on the other hand, the ideal gas is treated quantum mechanically, it can be demonstrated [206] that a Joule-Thomson effect exists (S 0) despite the lack of intermolecular interactions. 

Metal-functionalized dendritic assemblies have been demonstrated to be a fertile area with competitive potential for purely organic structures for their photonic properties [29]. This chapter aims at providing on overview of the different outstanding possibilities that dendrimers advantageously offer, first from a fundamental perspective by describing the main routes to build these nanometer-sized species, and then, by describing their photophysical properties, and eventually to the applications developed for these materials in various areas. 

P. Politzer, in E. Brandas and E. Kryachko (eds.). Fundamental Perspectives in Quantum Chemistry A Tribute Volume to the Memory of Per-Olov Lowdin, Kluwer, Dordrecht (The Netherlands), in press. 

The recent discovery that fullerene-related nanomaterials are formed under electrolytic conditions [14, 15] adds further technical and fundamental perspectives to the nanotube field. Using graphite electrodes immersed in molten LiCl under argon, nanotube production can be improved significantly. Depending upon the conditions, some 20-30% of the carbonaceous material formed may consist of graphitic nanotubes. Under other conditions quite different material is produced. 

Figure 1 portrays the relationship between the three fundamental perspectives. A break anywhere in the circular flow will hinder the product s market success. 

In a more fundamental perspective the concept of confining catalytically active salts on supports may be regarded as a branch of the common concept of supported liquid phase (SLP) catalysts, where a non- or low-volatile catalyst solution of, for example, pyrosulfates [26], hydrophilic polymer glycols [27-29], phthalates [22] or water (i.e. supported aqueous phase, SAP) [30-33] are deposited on a high-surface area porous support. 

Robert Bristow-Johnson. Wavetable Synthesis 101 A Fundamental Perspective. AES 101 Conference Preprint 4400, 1996. 

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