Locating Transition States By Computational Chemistry
Transition state structures can be determined by searching for first-order saddle points on the potential energy surface (PES). Such a saddle point is a point where there is a minimum in all dimensions but one. Almost all quantum-chemical methods (DFT, MP2 etc.) can be used to find transition states. However, locating them is often difficult and there is no method guaranteed to find the right transition state. There are many different methods of searching for transition states and different quantum chemistry program packages include different ones. Many methods of locating transition states also aim to find the minimum energy pathway (MEP) along the PES. Each method has its advantages and disadvantages depending on the particular reaction under investigation. Summaries of some of the main methods are given below.
Read more about this topic: Transition State
Famous quotes containing the words transition, states and/or chemistry:
“When I was going through my transition of being famous, I tried to ask God why was I here? what was my purpose? Surely, it wasn’t just to win three gold medals. There has to be more to this life than that.”
—Wilma Rudolph (1940–1994)
“I think those Southern writers [William Faulkner, Carson McCullers] have analyzed very carefully the buildup in the South of a special consciousness brought about by the self- condemnation resulting from slavery, the humiliation following the War Between the States and the hope, sometimes expressed timidly, for redemption.”
—Jimmy Carter (James Earl Carter, Jr.)
“...some sort of false logic has crept into our schools, for the people whom I have seen doing housework or cooking know nothing of botany or chemistry, and the people who know botany and chemistry do not cook or sweep. The conclusion seems to be, if one knows chemistry she must not cook or do housework.”
—Ellen Henrietta Swallow Richards (1842–1911)