Strong, weak hydrogen bonds, difference

This situation applies with weak hydrogen bonds at one extreme and very strong hydrogen bonds at the other with H and D confined to the same potential well. However, when the potential energy barrier has fallen sufficiently to allow the proton to escape the confines of its parent well, but leaves the deuteron trapped, then different values of the isotopic ratio can be observed (Fig. 7). The effect of isotopic exchange is now much more than merely one of doubling the reduced mass of the vibrating bond. When the proton is above the barrier, the force constant of the A—H bond, k A.—H),... 

Second, rate constants for intermolecular proton transfer obey the Brpnsted relationship, and the rates can be strongly influenced by electrostatics as well as the difference in the p/ a s for the two acids. Third, proton transfer can proceed at slower than diffusion-limited values with compounds forming weak hydrogen bonds in water. 

Molecular alignment in the monomer crystals is controlled by several intermolecular interactions, such as strong and weak hydrogen bonds, leading to the formation of various types of stereoregular polymers via a topochemical polymerization process. This approach to the stereocontrol of polymers differs from other conventional ways in the control of the propagating chain end using catalysts or additives in solution polymerization. 

Strong and weak hydrogen bonds obviously have very different properties. Table 11.2.2 lists the properties observed for different types of hydrogen bonds. 

Figure 12-1. The dependence of the Y -H distance of the strong and weak hydrogen bonds in the HAc complexes on different solvent medium...

Strong and weak hydrogen bonds have very different properties. A case can be made for the view that strong hydrogen bonds are quantitatively different in most of their properties from moderate or weak bonds [49]. 

These strong and weak hydrogen bonds are randomly and isotropically distributed in the ice structure and their populations should correspond to the ratio of the integrated peak areas. The observed value, low-energy mode to high-energy mode, is about 1 2 which agrees well with the assumption of the protons in the structure is complete disordered. The difference between the force... 

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