Molecular concept

Somor]ai G A 1998 Molecular concepts of heterogeneous catalysis J. Moi. Struct (Theochem) 424 101... 

Laschewsky, A. Molecular Concepts, Self-Organisation and Properties of Polysoaps. Vol. 124,... 

Herbert Morawetz, whom Mark hired at Brooklyn Poly in 1951, says that he believes that Mark is incapable of negative emotion, "or at least they are buried beyond retrieval". As an example, it is well known that Hermann Staudinger disliked Mark as a result of the events about the establishment of the macro-molecular concept. His dislike bordered on open contempt, but Mark steadfastly refused to openly criticize Staudinger. In... 

Solubility and kinetics methods for distinguishing adsorption from surface precipitation suffer from the fundamental weakness of being macroscopic approaches that do not involve a direct examination of the solid phase. Information about the composition of an aqueous solution phase is not sufficient to permit a clear inference of a sorption mechanism because the aqueous solution phase does not determine uniquely the nature of its contiguous solid phases, even at equilibrium (49). Perhaps more important is the fact that adsorption and surface precipitation are essentially molecular concepts on which strictly macroscopic approaches can provide no unambiguous data (12, 21). Molecular concepts can be studied only by molecular methods. 

In fact, the chemical industry often favors heterogeneous catalysis, which is also more than a century old (Sabatier was probably one of its real fathers), despite its so-far empirical nature. The development of better catalysts in heterogeneous catalysis has always relied on empirical improvement since it has been difficult to characterize active sites on the surfaces, as the so-called active sites are usually small in number(s). Presently, the number of accepted elementary steps (as defined above) is stiU Hmited to a few examples, mostly demonstrated by means of surface science [1-3] and the predictive approach, based on molecular concepts. 

In conclusion the results suggest strongly that the concept of a single site, which is a large step forward in catalysis on oxides, may also become as important in catalysis on metals. Scheme 3.27 indicates simple ideas as to how the control of a surface structure associated with the molecular concepts of mechanisms not only explains the existing results but also opens the way to rational design of future nanoparticles in metallic catalysts. 

The field of theoretical molecular sciences ranges from fundamental physical questions relevant to the molecular concept, through the statics and dynamics of isolated molecules, aggregates and materials, molecular properties and interactions, and the role of molecules in the biological sciences. Therefore, it involves the physical basis for geometric and electronic structure, states of aggregation, physical and chemical transformations, thermodynamic and kinetic properties, as well as unusual properties such as extreme flexibility or strong relativistic or quantum-field effects, extreme conditions such as intense radiation fields or interaction with the continuum, and the specificity ofbiochemical reactions. 

The chapters in this volume illustrate how molecular concepts underlie catalysis. They illustrate how modern concepts of biology are influencing catalysis and catalyst discovery how concepts of homogeneous and surface catalysis have merged (a theme that is evident in the preceding several volumes of the Advances), exemplified by dendrimer catalysts that have properties of both molecules and surfaces and how concepts of molecular catalysis by bases have influenced the development of new solid-base catalysts and fundamental understanding of how they function. 

Rhodes DR, Kalyana-Sundaram S, Tomlins SA, et al. (2007) Molecular concepts analysis links tumors, pathways, mechanisms, and drugs. Neoplasia 9, 443-54. 

GENERAL MOLECULAR CONCEPTS OF DRUG RECEPTOR ACTION... 

Cotgreave IA, Morgenstern R, Jernstrom B, et al. Current molecular concepts in toxicology. In Ballantyne B, Marrs TC, Syversen T, eds. General and Applied Toxicology. Vol. 1. 2nd ed. London Macmillan. 

Physical chemists of the current generation can hardly imagine how atomic and molecular concepts were once doubted by serious scientists, even into the early 20th century Our current enlightenment reflects the debt that we owe to Boltzmann, Gibbs, Van der Waals, and other pioneer theorists. 

Boltzmann s tombstone in Vienna bears the famous formula 5 = k log W (W = Wahrscheinlichkeit—probability) that was a signature of his audacious concepts. The alternative formula (13.69) (which reduces to Boltzmann s in the limit of equal a priori probabilities pa) was ultimately developed by Gibbs, Shannon, and others in a more general and productive way (see Sidebar 13.4), but the key step of employing probability to trump Newtonian determinism was his. Boltzmann was long identified with efforts to establish the //-theorem and Boltzmann equation within the context of classical mechanics, but each such effort to justify the second law (or existence of atoms) in the strict framework of Newtonian dynamics proved futile. Boltzmann s deep intuition to elevate probability to a primary physical principle therefore played a key role in efforts to find improved foundation for atomic and molecular concepts in the pre-quantum era. 

We are forced to abandon naive molecular conceptions of direct impact... 

Morrison DC, Alving CR (1984) Molecular concepts of lipid A, Rev Infect Diseases 6 427... 

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