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:
“International relations is security, it’s trade relations, it’s power games. It’s not good-and-bad. But what I saw in Yugoslavia was pure evil. Not ethnic hatred—that’s only like a label. I really had a feeling there that I am observing unleashed human evil ...”
—Natasha Dudinska (b. c. 1967)
“The most remarkable aspect of the transition we are living through is not so much the passage from want to affluence as the passage from labor to leisure.... Leisure contains the future, it is the new horizon.... The prospect then is one of unremitting labor to bequeath to future generations a chance of founding a society of leisure that will overcome the demands and compulsions of productive labor so that time may be devoted to creative activities or simply to pleasure and happiness.”
—Henri Lefebvre (b. 1901)
“I cannot say what poetry is; I know that our sufferings and our concentrated joy, our states of plunging far and dark and turning to come back to the world—so that the moment of intense turning seems still and universal—all are here, in a music like the music of our time, like the hero and like the anonymous forgotten; and there is an exchange here in which our lives are met, and created.”
—Muriel Rukeyser (1913–1980)