How group increment methods may be used to predict standard enthalpies of formation of alkanes is outlined as an undergraduate computational chemistry experiment. The experiment requires input and output data sets. Although users may create their own data sets, both sets are provided. The input data set contains experimentally determined gas-phase standard enthalpies of formation and calculated steric energies for 10 alkanes. The steric energy for an alkane is calculated via a Molecular Mechanics approach employing Allinger's MM3 force field. Linear regression analysis on data contained in the input data set generates the coefficients that are used with the output data set to calculate standard enthalpies of formation for 15 alkanes. The average absolute error for the calculated standard enthalpies of formation is 1.22 kcal/mol. The experiment is highly suited to those interested in incorporating more computational chemistry in their curricula. In this regard, it is ideally suited for a physical chemistry laboratory, but it may be used in an organic chemistry course as well.
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