Properties of Molecules by Direct Calculation

Determination of intrinsic molecular properties is sometimes the final goal of experimental or theoretical work, but sometimes it is a means to greater chemical understanding. Properties characterize a molecule, and as such they are raw material for construaing many chemical concepts. Structural correlations with properties are an example, as are associations of functionality with specific properties. Once firmly established, such correlations become working knowledge for many chemists. 

The theorist s goal in studying molecular properties has been to use fundamental physical theory to deduce, calculate, or extract specific molecular properties not already known. The theoretical foundation for accomplishing this is a solid one and supports the layers of sophisticated computational treatments that have been built atop it. These were spurred on by dramatic improvements in computing machinery. There is now tremendous capability in many laboratories for directly computing a host of molecular properties for small and large molecules. That is the focus of this chapter. 

In general, quantum mechanical descriptions of molecules imply that we may explore three types of molecular features structural parameters, energy or energies of molecular states, and responses to perturbations. The last of 

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Clifford E. Dykstra, Joseph D. Augspurger, Bernard Kirtman, and David J. Malik, Properties of Molecules by Direct Calculation. 

Dykstra CE, Augspurger JD, Kirtman B, Malik DJ. Properties of molecules by direct calculation. In Lipkowitz KB, Boyd DB, eds. Reviews in Computational Chemistry. Vol. 1. New York VCH, 1990 83-118. 

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