Intramolecular interactions, effect

It must be kept in mind that the Goodrich treatment separates out contributions to intermolecular interactions that arise from film expansion. The differences in film expansion are a reflection of conformation and are accounted for in the pure meso- and ( )-films. However, since ( )- and meso-film components do interact, the intramolecular contribution to film compression may be altered. This effect would arise from conformational perturbations as molecules interact, thereby precluding complete separation of inter- and intra-molecular contributions to the thermodynamics of compression. However, these complicating factors can be mitigated by comparing several molecules with varying structures, as has been carried out in this instance. 

Some other mechanisms will be discussed in later sections The Grant-Cheney formulation (88) of steric compression effects will appear in the context of y-gauche substituent effects (Section III-C), and hyperconjugative orbital interactions will be cited in interpretations of y-anti substituent (Section III-D) and intramolecular interaction effects (Section IV). 

Cage effect, solvent, 169, 216, 227 Calvin cycle, 283 Character table, 36 Charge transfer complexes, 83 from metal to ligand, 269 interaction, 286 intramolecular transitions, 85 ligand to metal (CTLM), 269 mechanism. 182 transition, characteristics of, 85 transitions, to solvent, 86, 102, 276 Chemical lasers, 222 spectroscopy, 230 Chemiluminescence, 160, 265 reactions, 266... 

In other words, it is assumed here that the particles are surrounded by a isotropic viscous (not viscoelastic) liquid, and is a friction coefficient of the particle in viscous liquid. The second term represents the elastic force due to the nearest Brownian particles along the chain, and the third term is the direct short-ranged interaction (excluded volume effects, see Section 1.5) between all the Brownian particles. The last term represents the random thermal force defined through multiple interparticle interactions. The hydrodynamic interaction and intramolecular friction forces (internal viscosity or kinetic stiffness), which arise when the macromolecular coil is deformed (see Sections 2.2 and 2.4), are omitted here. 

The results shown in Table 5.11 show that the addition of hydrogen from the equatorial side is hindered by the presence of the ring oxygen or nitrogen atom. The results have been explained by a similar intramolecular interaction effect of the lone-pair electrons of oxygen or nitrogen atom. 

In addition to the intermolecular interactions, the intramolecular interactions may also be taken into account in a similar way. This rather limited approach may nevertheless be useful for calculating molecular conformation and even molecular symmetry. Deviations from the ideal conformations and symmetries may also be estimated this way, provided they are due to steric effects. 

More recently, a spirobenzopyran dimer bridged by a diaza-18-crown-6 moiety through the 8-position (67) was developed by Kimura and co-workers.119 121 Crowned bis(spirobenzopyran) 67 shows a similar coloration selectivity to that of 63. Complexation of multivalent metals, especially Ca2+ and La3, by 67 enhanced the isomerization of the spirobenzopyran moiety to the corresponding merocyanine form due to an effective intramolecular interaction between a crown-complexed cation and the two phenolate anions in the cation complexes of the merocyanine form. 

Finally, structure-based predictive software is commercially available (such as CHROMDREAM, CHROMSWORD or ELUEX) for mobile phase optimisation in RPC. This software incorporates some features of the expert system, as it predicts the retention on the basis of the molecular structures of all sample components (which should be known) and the known behaviour of model compounds on various HPLC columns. No initial experimental runs are necessary as the retention data are calculated from the additive contributions of the individual structural elements to the retention, contained in the software databa.se and consequently optimum composition of the mobile phase is suggested. Such predictions are necessarily only approximate, do not take into account stereochemical and intramolecular interaction effects, and predicted separation conditions can be used rather as the recommendation for the initial experimental run in the subsequent optimisation procedure. 

The choice of eluent system depends on the polymer type. For most non-ionic hydrophilic polymers, water can be used. However much more complex eluent systems are needed, for anionic and cationic polymers where interactions with the column based on ion exclusion, inclusion and exchange, adsorption by hydrogen bonding or hydrophobic interactions and intramolecular electrostatic effects, are possible. This can often make method development in aqueous SEC extremely difficult and time-consuming. 

Abnormal (3 effects exist for substituents in the 3-position. This can be interpreted in terms of intramolecular interactions (electronic, steric and/or by hydrogen bridging) between the substituents and the neighbouring carbonyl group. Such interaction effects are discussed below. 

The above cis effect is significant because of its apparent role as the nascent interaction in intramolecular hydrogen exchange processes. The intermediate is... 

The spectrum of the triboluminescence (i.e. emission caused by mechanical stress) of U0a(N03)2,6H20 is similar to that for photo-induced luminescence.167 Possible causes for this effect are electrical excitation (i.e. pressure-induced electrochemiluminescence), intermolecular interactions, and intramolecular deformations. Arguments are presented to show that the third mechanism is not important in this case. Other relevant publications are concerned with electrochemiluminescence of UOa8+ in perchloric acid,168 170 171 173 174 absorption and luminescence spectra of UOa2+ in solution,16 and detailed analyses of the emission spectrum of crystalline UOa2+ salts at low temperatures.170-174... 

Temperature dependence of J couplings in the liquid phase may originate in both intramolecular nuclear motions and intermolecular interaction effects. In the review period, experimental and theoretical studies of this dependence were reported. 

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