Hypohalous acids (HOF, HOCl and HOBr), known for their oxidative abilities, are involved in stratospheric reaction chains. The current computational study concentrates on their ability to form dimeric complexes. Interaction energy partitioning for selected dimers (also with participation of water) was carried out on the basis of symmetry-adapted perturbation theory (SAPT). Hydrogen and halogen bonds formed in these complexes are discussed. Additionally, DFT calculations on the studied dimers are presented. DFT predicts energy trends generally well, even if the actual interaction energy values can be underestimated. Thus, DFT is expected to provide good description of the ice surface reactivity of hypohalous acids. (C) 2008 Elsevier B.V. All rights reserved.