The Philosophy of Computational Chemistry

Computational chemistry is the culmination (to date) of the view that chemistry is best understood as the manifestation of the behavior of atoms and molecules, and that these are real entities rather than merely convenient intellectual models [4]. It is 

In computational chemistry we take the view that we are simulating the behaviour of real physical entities, albeit with the aid of intellectual models and that as our models improve they reflect more accurately the behavior of atoms and molecules in the real world. 

Computational chemistry allows one to calculate molecular geometries, reactivities, spectra, and other properties. It employs  

Molecular mechanics - based on a ball-and-springs model of molecules Ab initio methods - based on approximate solutions of the Schrodinger equation without appeal to fitting to experiment 

Semiempirical methods - based on approximate solutions of the Schrodinger equation with appeal to fitting to experiment (i.e. using parameterization) Density functional theory (DFT) methods - based on approximate solutions of the Schrodinger equation, bypassing the wavefunction that is a central feature of ab initio and semiempirical methods Molecular dynamics methods study molecules in motion. 

Computational chemistry is the culmination (to date) of the view that chemistry is best understood as the manifestation of the behavior of atoms and molecules, and that these are real entities rather than merely convenient intellectual models [1]. It is a detailed physical and mathematical affirmation of a trend that hitherto found its boldest expression in the structural formulas of organic chemistry [2], and it is the unequivocal negation of the till recently trendy assertion [3] that science is a kind of game played with paradigms [4]. 

---