The concept of resonance-assisted hydrogen bonds (RAHBs) is one of the most frequently used concepts in structural chemistry. Computed equation-of-motion coupled cluster singles and doubles (EOM-CCSD) O-O and N-N coupling constants through intramolecular X-H-X hydrogen bonds ((2h)Jx-x) and MP2 H-1 chemical shifts of the X-H-X protons have been used to investigate RAHBs in model saturated and unsaturated systems. The computed results suggest that the NMR properties of these molecules do not receive significant contributions from resonance, but are a consequence of the sigma-skeleton framework. (c) 2005 Elsevier B.V. All rights reserved.