MP2 AND DENSITY-FUNCTIONAL STUDIES OF HYDROGEN-BONDING IN MODEL TRIOSES - D-(-GLYCERALDEHYDE AND DIHYDROXYACETONE())

Among the conformers of the title compounds, all stable structures fou nd reveal hydrogen bonding to an sp(2) oxygen atom in five- or six-mem bered rings and usually cooperative effects. Nonlocal density function al calculations using different functionals prove the applicability of DFT to study geometries of systems containing intramolecular hydrogen bonds. The hydrogen bond parameters obtained applying the B3LYP appro ximation exhibit perfect agreement with those calculated at the MP2 le vel. The local gradient correction does not provide encouraging result s.