Molecular orbital computations on lipids: an ab initio exploratory study on the conformations of glycerol and its fluorine congeners

In order to characterize the set of topologically probable glycerol-3-phosphate backbone conformers, ab initio calculations were performed on glycerol as a preliminary study. Ab initio calculations were also completed for selected congeners of glycerol, such as 1,2-difluoro-3-hydroxylpropane and 1,2,3-trifluoropropane, in order to model the effects of changing electron densities on the glycerol-3-phosphate backbone geometry. The results show that conformations having intramolecular hydrogen bonds have a lower relative energy. The O-H stretching frequencies computed in different glycerol conformations were largely dependent on ϕi and ψi backbone dihedrals.