Geometrical Isotope Effects on Chemical Bonding in Hydrogen Bonded Systems: Combining Nuclear-Electronic Orbital DFT and Energy Decomposition Analysis.

ABSTRACT: We investigated primary and secondary geometric isotope effects (H, D, T) on charge-inverted hydrogen bonds (CIHB) and dihydrogen bonds (DHB) using nuclear-electronic orbital density functional theory (NEO-DFT). The dianionic but electrophilic boron cluster [B₁₂H₁₂]^2- served as a bonding partner, exhibiting a negatively polarized hydrogen atom in the BH bond. CIHB systems included interactions with Lewis acids (AlH₃, BH₃, GaH₃) and carbenes (CF₂, CCl₂, CBr₂), while DHBs were analyzed with NH₃, HF, HCl, and HBr. Isotope substitution systematically decreased intermolecular and intramolecular bond lengths (H > D > T). Energy decomposition analysis (EDA) combined with Hirshfeld partia

SUBMITTER: Khan RU 

PROVIDER: S-EPMC12423738 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature