The first example we consider is a reaction that forms a mixture of olefin isomers, as shown in Fig. . The Wittig olefination of benzaldehyde (1a) forms a mixture of E (1b) and Z (1c) olefin isomers, resulting in a simple candidate library of three compounds (two possible products and one starting material). NMR parameters for all candidate compounds were calculated and calibrated as described above, to yield a set of predicted NMR spectra (Fig. ).