The effect produced by the formation of hydrogen bonded complexes on the optical rotatory power of two oxiranes has been studied theoretically using DFT and MP2 methods. The results obtained have been rationalized based on a model oxirane where the chirality is induced by the HB formed. In addition, the effect of solvent continuum models has been calculated for the complexes. (c) 2005 Elsevier B.V. All rights reserved.