Observing Transition States
Because of the rules of quantum mechanics, the transition state cannot be captured or directly observed; the population at that point is zero. This is sometimes expressed by stating that the transition state has a 'fleeting existence'. However, cleverly manipulated spectroscopic techniques can get us as close as the timescale of the technique will allow us. Femtochemical IR spectroscopy was developed for precisely that reason, and it is possible to probe molecular structure extremely close to the transition point. Often along the reaction coordinate reactive intermediates are present not much lower in energy from a transition state making it difficult to distinguish between the two.
Read more about this topic: Transition State
Famous quotes containing the words observing, transition and/or states:
“No one can doubt, that the convention for the distinction of property, and for the stability of possession, is of all circumstances the most necessary to the establishment of human society, and that after the agreement for the fixing and observing of this rule, there remains little or nothing to be done towards settling a perfect harmony and concord.”
—David Hume (1711–1776)
“The god or hero of the sculptor is always represented in a transition from that which is representable to the senses, to that which is not.”
—Ralph Waldo Emerson (1803–1882)
“That Cabot merely landed on the uninhabitable shore of Labrador gave the English no just title to New England, or to the United States generally, any more than to Patagonia.”
—Henry David Thoreau (1817–1862)