# An Introduction to Geometry Optimization

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Geometry Optimization Lab Activity

Geometry Optimization Main Page

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• Geometry optimization is a technique used by all computational scientists. It is a method of taking rough geometric approximations and making them as exact as possible. It is a series of iterations performed on the molecule until the energy of the molecule has reached a minimum.

To begin the process, you must determine an initial geometry, initial basis set and then the chemistry program completes a series of computations. As you have learned in previous lessons, there are three types of calculations that may be performed:

Each of these calculations work to optimize the geometry and depending on which set you use, will determine how exact your optimization will be. These computations not only give you a new geometry, but also a new energy for the molecule. This process is repeated until the molecular energy reaches its minimum. The following flow chart explains the sequence of events which occur in order to optimize a basis set.

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