Class Summary 11/15/04

11/15 Chemical Reactions and Dynamics

DG determines reaction properties (technically, the chemical potential, m does)

The geometric changes undergone by reactants as they go to products is called the “reaction pathway” (or “reaction coordinate”)

Single-step reactions “Concerted reactions”

“Synchronous reactions” = bond=breaking and making are equal

“Asynchronous reactions” = Either bond-breaking or making is favoured

Multi-step reactions maxima = transition state

local minima are likely intermediates

Transition state Free energy maximum (in a single coordinate)

Saddle point

Single imaginary frequency

“Point of minimum flux” = BOTTLE NECK (Eyring), G is a saddlepoint

Transition State Theory (TST) proposed the “elementary step”

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