Some Notes about Terminology

Additional linguistic dilemmas are encountered in this area of research. For example, these weak chemical forces are sometimes referred to as nonbonding interactions despite meeting Pauling s utilitarian definition of a chemical bond introduced in 1939 (which is still one of the most useful and most widely used) ° 

There is a chemical bond between two atoms or groups of atoms in the case 

The term noncovalent interaction does not completely resolve the matter since ionic interactions (e.g., salt bridges) are frequently included in this category, particularly in the biochemistry community. In this work, the moniker weak noncovalent interaction is used to denote the continuum of weak chemical forces between electrically uncharged molecules (and/or atoms). 

---

Special note about coverages Because of the nature of the different reactants and adlayers, a common basis for reporting surface coverage is not practical. This creates confusion as some coverages (carbon) are reported as a fraction of a saturated monolayer of adsorbate, while others (carbon monoxide and ethylidyne) are reported as a fraction of the substrate surface atom density. We therefore adopt lUPAC terminology [3839] and use the term monolayer to indicate the maximum amount of adsorbate for which each adsorbed atom or molecule is in direct contact with the substrate. A full monolayer corresponds to 0 = 1, as previously noted for carbon. Coverages of carbon monoxide and ethylidyne will be reported as ratios of adsorbate species per substrate surface atom. The reader should note that this definition of monolayer differs from our previous usage as well as that of some other researchers. 

This article contains an interesting note about the structure While molecular structure is a central concept in chemistry and physics, it should be remembered that for an isolated gas phase molecule in field-free space the most information that can be acquired is the average values of structural parameters (i.e., bond distances and angles). This point becomes apparent when molecular calculations are done without the B-O approximation - an almost universal approximation in quantum chemistry. While this approximation is extremely useful and has largely defined the terminology of modern spectroscopy, it also hides some simple quantum mechanical truths about the systems we study. ... 

When objective measurement of performance capacities has been incorporated into many clinical trials, concepts and tools from human performance engineering can facilitate the selection of variables and shed some Hght on issues noted above. In either safety- or efficacy-oriented studies, study variable selection can be characterized as a two-step process (1) identification of the factors in question (Table 82.1) and (2) selection of the relevant performance capacities to be measured and associated measurement instruments. This Hnk between these two steps often represents a challenge to researchers for a number of reasons. First, duality in terminology must be overcome. Concerns about an intervention are typically initially identified with negative terms such as dizziness and not in terms of performance capacities such as postural stability. Human performance models based on systems engineering concepts [Kondraske, 1995] can be used to facilitate the translation of both formal and lay terms used to identify adverse effects to relevant performance capacities to be measured, as shown in Table 82.1. 

---