An Overview of Computational Chemistry

There are two broad areas within computational chemistry devoted to the structure of molecules and their reactivity molecular mechanics and electronic structure theory. They both perform the same basic types of calculations  

Exploring Chemistry with Electronic Structure Methods 

Computing the vibrational frequencies of molecules resulting from interatomic motion within the molecule. Frequencies depend on the second derivative of the energy with respect to atomic structure, and frequency calculations may also predict other properties which depend on second derivatives. Frequency calculations are not possible or practical for all computational chemistry methods. 

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