Variational transition state theory is a refinement of transition state theory. When using transition state theory to estimate a chemical reaction rate, the dividing surface is taken to be a surface that intersects a first-order saddle point and is also perpendicular to the reaction coordinate in all other dimensions. When using variational transition state theory, the position of the dividing surface between reactant and product regions is variationally optimized to minimize the reaction rate. This minimizes the effects of recrossing, and gives a much more accurate result.
Famous quotes containing the words transition, state and/or theory:
“There is not any present moment that is unconnected with some future one. The life of every man is a continued chain of incidents, each link of which hangs upon the former. The transition from cause to effect, from event to event, is often carried on by secret steps, which our foresight cannot divine, and our sagacity is unable to trace. Evil may at some future period bring forth good; and good may bring forth evil, both equally unexpected.”
—Joseph Addison (1672–1719)
“Exploitation and oppression is not a matter of race. It is the system, the apparatus of world-wide brigandage called imperialism, which made the Powers behave the way they did. I have no illusions on this score, nor do I believe that any Asian nation or African nation, in the same state of dominance, and with the same system of colonial profit-amassing and plunder, would have behaved otherwise.”
—Han Suyin (b. 1917)
“The struggle for existence holds as much in the intellectual as in the physical world. A theory is a species of thinking, and its right to exist is coextensive with its power of resisting extinction by its rivals.”
—Thomas Henry Huxley (1825–95)