The effects of angular distortions on the H-bond energy are computed in both neutral and ionic complexes. F3CH, NCH, and HNCH+ are taken as CH donors and HCNH, HCNH+, and NH4+ are NH donors. Ionic complexes are more strongly bound and suffer a greater loss of H-bond energy upon angular distortion. However, when bending force constants k are normalized against intrinsic H-bond strength E-b, the k/E-b ratios are similar, only slightly larger for NH than for CH donors, and with only small perturbations caused by overall charge. The source of destabilization arising from angular deformation is traced to exchange repulsion. (C) 2015 Elsevier B.V. All rights reserved.