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Q: The equations in your scientific pages are messed up. What's up
with that?
A: You are probably using Firefox as your browser. See this
Firefox Font Fix.
Q: What exactly is "Computational Chemistry"?
A: There are four main branches of chemistry: Physical Chemistry,
Inorganic Chemistry, Organic Chemistry and Biochemistry. Within Physical Chemistry
there developed a subcategory called Theoretical Chemistry. With the development
of quantum mechanics and the rise of powerful computers other terms for this
field began to appear, such as Quantum Chemistry and Computational Chemistry. The three
terms Theoretical, Computational and Quantum Chemistry intimately overlap. It can
fairly be said that Computational Chemistry is the use of computer programs to
implement Quantum Chemistry. Computational Chemistry seeks to predict the behaviour
of chemical reactions and the properties of molecules and compounds using the
principles of quantum mechanics, statistical mechanics and thermodynamics. The kinds
of information that are attainable include heats of reaction, mechanisms and
pathways of reaction, reaction rates and spectroscopic properties.
Q: You seem to have done alot of work on "electron correlation energy". What
exactly is that?
A: It is one of the biggest problems in Computational Chemistry. It is a
big problem because we cannot write down a mathematical expression for it in a
closed algebraic form. We are forced to make more and more complex approximations
to it that cost more and more computer time. This places a technical limit
on the size of molecular systems that we can accurately treat. Conceptually, all one
needs to realize is that like charges repel each other. This means that all the electrons
which are trapped together in a quantum system such as a molecule tend to "stay in step"
with each other to a certain degree as they move around. It is this "staying in step"
or correlation that we cannot write an explicit equation for.