Ab Initio Computational Studies of Chiral Discrimination Landscapes

The ab initio calculations provide important theoretical input to complement our experiments. These theoretical predictions are used to guide initial spectral searches and to further interpret our experimental results.

Here is an example of a geometry optimization (shown on the right) for the L-trans-propyleneimine (PI)--- (+)- and (-)-H2O2 diastereomers using Gaussian98/03, at the MP2/aug-cc-pVDZ level. Further calculations indicate a much larger chiraldiastaltic energy for the trans-PI---H2O2 diastereomers than for the cis ones.

Below is a selected cut of the calculated potential energy surface for the diastereomer L-cis-PI---(+)-H2O2 and the corresponding contour plot. This region corresponds to the global minimum for this diastereomer. The unit of the color bar is mhartree. This work is the result of the first Canadian Internetworked Scientific Supercomputer (CISS) experiment.

Ref: Z. Su and Y. Xu, Phys. Chem. Chem. Phys., 2005, 7, 2554-2560.