Elements theoretical

Peterson, K.A. and Puzzarini, C. (2005) Systematically convergent basis sets for transition metals. II. Pseudopotential-based correlation consistent basis sets for the group 11 (Cu, Ag, Au) and 12 (Zn, Cd, Hg) elements. Theoretical Chemistry Accounts, 114, 283-296. 

Flerov, G.N. Cartoon in Proceedings of the Nobel Symposium 27. Super-Heavy Elements - Theoretical Predictions and Experimental Generation , Ronneby, Sweden, 11-14 June 1974, Physica Scripta 10A, (1974) 1. 

The abihty of these gases to form true chemical compounds with other atoms is limited to the heavier members of the group, krypton, xenon, and radon, where the first ionization energies are reduced to a level comparable with other chemically active elements. Theoretical studies, however, have indicated that it may be possible to isolate helium derivatives, such as MeBeHe. Many of the compounds are prepared at low temperature and characterized through spectroscopic techniques. More recently, multinuclear NMR has emerged as an extremely useful characterization technique. ... 

Computational chemistry contains a strong practical element. Theoretical methods must be translated into working computer programs in order to produce results. Different algorithms, however, may display different types of behaviour in practice, and... 

Interestingly, Fajans seems to have preferred to use the terms theoretical element and practical element. Theoretical elements were truly fundamental for Fajans, whereas practical elements were those that had been shown to have resisted decomposition thus far. From the point of view of this essay, this point is significant because it emphasizes that at the beginning of the century the philosophical notion of abstract element (Paneth) or theoretical element (Fajans) was widely held. Indeed, here are two chemists who disagreed on many aspects of the new radiochemistry but took it for granted that the nature of elements consisted in a dual observable and nonobservable nature. It is doubtful whether a contemporary chemist would have arrived at Paneth s element scheme or indeed Fajans s alternative in the absence of such a philosophical appreciation of the subject matter. 

Tomcik has reviewed fundamental aspects of array performance when arrays are fabricated with very closely spaced microelectrode elements [1]. Array elements of micrometer dimensions, separated by very small gaps, have overlapping diffusimi layers, and allow interactions between adjacent elements. Theoretical studies and basic applications of affected phenomena, in comparison with isolated array elements, include collection efficiency and redox cycling. The detection of catecholamines is considered. 

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