Bond stretch strain

Bond-Stretch Isomerism and the Reactivity of some Highly Strained Tricyclic Hydrocarbons towards Acids and Bases... 

Steric strain differences in the monomer and polymer arising from bond angle deformation, bond stretching, or interactions between nonbonded atoms. 

Molecular Mechanics Models. Methods for structure, conformation and strain energy calculation based on bond stretching, angle bending and torsional distortions, together with Non-Bonded Interactions, and parameterized to fit experimental data. 

Strain of various sorts (Huisgen and Ott, 1959) has been suggested as the cause of at least part of the acceleration of rate caused by enzymes. The most popular theory described enzymes as a rack on which the substrate was stretched. Electrostatic or other forces caused strong interactions between the enzyme and two ends of the substrate and pulled or bent it in such a way as to weaken the fissile bond. The strain was postulated to lower the energy required to reach the transition state (Eyring et al., 1954 Lumry, 1959). 

Vibrational spectroscopy reveals that, for small displacements from equilibrium, energy variations associated with bond angle deformation are as well modeled by polynomial expansions as are variations associated with bond stretching. Thus, the typical force field function for angle strain energy is... 

Elastic materials strain instantaneously when stretched and just as quickly return to their original state once the stress is removed. Viscoelastic materials have elements of both of these properties and, as such, exhibit time dependent strain. Whereas elasticity is usually the result of bond stretching along crystallographic planes in an ordered solid, viscoelasticity is the result of the diffusion of atoms or molecules inside of an amorphous material [3-6],... 

The major source of the disorder energy is the bond strain within the random network. Phillips (1979) proposed a model to explain the relation between network coordination and disorder. A four-fold continuous random network is overcoordinated, in the sense that there are too many bonding constraints compared to the number of degrees of freedom. The constraints are attributed to the bond stretching and bending forces, so that for a network of coordination Z , their number, NciZJ is. 

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