Computational Chemistry techniques: covering orders of magnitude in space, time, and accuracy

Abstract

Computational Chemistry is the branch of chemistry which uses extensively computer models to simulate real systems. Model systems are made to fit the real system in intended respects and with the intended accuracy of the creator or user of the model. The building blocks of model systems and the interactions between them are abstractions of the building blocks of real system and the interactions between them. In computer models a system must be represented by data which are stored in data structures, the interactions between them are represented by mathematical functions or sets of rules. Properties of the model system are calculated with various algorithms, both numerical and non-numerical. A computational chemist must decide which computer model is best suited to represent a real system so that its essential properties can be simulated as intended. Doing computational chemistry means to apply the right computer models to describe a real system or, if necessary, design new computer models.