Inter- and intramolecular interactions

Suppose we are using an empirical energy function such as the following to describe the inter- and intramolecular interactions in our ethanol/ethane thiol system ... 

The systematic study of piezochromism is a relatively new field. It is clear that, even within the restricted definition used here, many more systems win be found which exhibit piezochromic behavior. It is quite possible to find a variety of potential appUcations of this phenomenon. Many of them center around the estimation of the pressure or stress in some kind of restricted or localized geometry, eg, under a localized impact or shock in a crystal or polymer film, in such a film under tension or compression, or at the interface between bearings. More generally it conveys some basic information about inter- and intramolecular interactions that is useful in understanding processes at atmospheric pressure as well as under compression. 

Once the model of a ligand-receptor complex is built, its stability should be evaluated. Simple molecular mechanics optimization of the putative ligand-receptor complex leads only to the identification of the closest local minimum. However, molecular mechanics optimization of molecules lacks two crucial properties of real molecular systems temperature and, consequently, motion. Molecular dynamics studies the time-dependent evolution of coordinates of complex multimolecular systems as a function of inter- and intramolecular interactions (see Chapter 3). Because simulations are usually performed at nonnal temperature (—300 K), relatively low energy barriers, on the order of kT (0.6 kcal), can... 

The biological function of biopolymers such as polypeptides, proteins, nucleic acids etc. depends strongly on their ordered structure which is determined by the pattern of inter- and intramolecular interactions given by the primary structure. 

The hydroxypropyl derivative of guar GaM (HPG) was prepared with propylene oxide in the presence of an alkaline catalyst. HPG was subsequently etherified as such with docosylglycidyl ether in isopropanol and presence of an alkaline catalyst [432]. The peculiar features of the long-chain hydrophobic derivatives were ascribed to a balance between inter- and intramolecular interactions, which is mainly governed by the local stress field. 

Molecular chaperones are able to temporarily stabihze unfolded or partially folded proteins and prevent inappropriate inter- and intramolecular interactions. They reduce the free concentration of aggregation-sensitive folding in-... 

Gakh, E.G., Dougall, D.K., and Baker, D.C., Proton nuclear magnetic resonance studies of monoacylated anthocyanins from the wild carrot part 1. Inter- and intramolecular interactions in solution, Phytochem. Anal., 9, 28, 1998. 

The relevance of lipophilicity in pharmacodynamics is due to the fact that inter-and intramolecular interactions governing lipophiUcity (Sections 12.1.1.2 and 12.1.1.3) are of the same nature as those that govern drug recognition and binding to biological sites of action [3, 4, 15]. 

Bulky substituents at tetravalent silicon centers are the structural key element of sterically overcrowded compounds with extraordinary properties Inter- and intramolecular interactions of the bulky ligands can be studied in detail and allow an assessment of the ligands influence on structure and reactivity. 

While much of the emphasis on inter- and intramolecular interactions, secondary bonding, and forces associated with association and dissociation involve attractive forces, we are finding that phobic effects are also important and for some systems are actually the major factors. Briefly, this can be described by the sayings the enemy of my enemy is my friend, or given the choice between bad and worse, bad wins out. Formation of many self-assemblies is due in large measure to such phobic factors. 

Three fundamental properties that play key roles in determining covalent and/or nonco-valent interactions are the electrostatic potential V(r), the ionization energy 7 (sometimes written IE) and the polarizability a. All three can be obtained experimentally. It is primarily in terms of these properties that we will examine the inter- and intramolecular interactions of hydroxylamines, oximes and hydroxamic acids. Accordingly we shall first briefly discuss F(r), I and a. 

Changes in the Inter- and intramolecular interaction and in the structure of carbanion pairs on adding cation-binding ligands (ethers, crown ethers, poly-amines) is briefly reviewed. 

Kronman, M. J. and Andreotti, R. E. 1964. Inter- and intramolecular interactions of a-lactalbumin. I. The apparent heterogeneity at acid pH. Biochemistry 3, 1145-1151. 

One of the most prominent hydrogen-bonded systems is DNA. Despite numerous experimental and theoretical investigations on vibrational spectra of nucleic acid bases [7-13], information on inter- and intramolecular interactions in base pairs and DNA oligomers is still limited [14-25]. A recent example is the work on single adenine-uracil (AU) base pairs in the Watson-Crick geometry in solution, which showed an enhancement of vibrational energy... 

In the discussion of the loading and curing step, we have focused on the conformation of the silicon side of the aminosilane molecules. Siloxane bond formation and effect of hydrolysis of the alkoxy groups have been characterized clearly. The special reactivity of aminosilanes, compared to other organosilanes, however, is due to the presence of the amino group inside the molecule. The inter- and intramolecular interactions of this group cause special stability and reactivity according to the conditions used. Therefore we will now focus on this side of the bifunctional molecule. 

The dihalogenated 1,2,5-oxaphosphastannolane dimerizes as a result of an intermolecular O —> Sn coordination to give a diastereomeric mixture147 the structure of one of them (18) is shown. As a result of both inter- and intramolecular interactions the coordination... 

In Sections 5.2.1 and 5.2.2, it was stated that the samples must be matrix-effect-free for univariate models, e.g., inter- and intramolecular interactions must not be present. The standard addition method can be used to correct sample matrix effects. It should be noted that most descriptions of the standard addition method in the literature use a model form, where the instrument response signifies the dependent variable, and... 

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