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 make this direct statement to the American people that there is far less chance of the United States getting into war, if we do all we can now to support the nations defending themselves against attack by the Axis than if we acquiesce in their defeat, submit tamely to an Axis victory, and wait our turn to be the object of attack in another war later on.”
—Franklin D. Roosevelt (1882–1945)
“If thought makes free, so does the moral sentiment. The mixtures of spiritual chemistry refuse to be analyzed.”
—Ralph Waldo Emerson (1803–1882)