Methylpentane model structure

From their work on methylcyclopentane and methylpentanes Garin et al.3S0 conclude that BS is at a maximum over a Pt(557) surface. On the basis of this they propose that more than 1 metal atom must operate in the BS isomerization. They present a variety of models in which at least 2 metal atoms at a surface step are involved in the initial adsorption process. Davis et al.351 conclude also that BS is probably structure sensitive. However, they... 

Representation of molecular structure via chemical graphs requires the characterization of the graph in a numerical sense. In a mathematical model such as a QSAR equation, one or more numerical variables of structure must be entered into the equation for each molecule in the data set. These numerical quantities must distinguish among the various structures in the data. For example, if the hexane isomers are involved in the data, the structure variables must represent the differences among hexane, 3-methylpentane, 2-methylpentane, 2,2-dimethylbutane and so on. 

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