title: Solid-State17O NMR Reveals Hydrogen-Bonding Energetics: Not All Low-Barrier Hydrogen Bonds Are Strong.
abstract: While NMR and IR spectroscopic signatures and structural characteristics of low-barrier hydrogen bond (LBHB) formation are well documented in the literature, direct measurement of the LBHB energy is difficult. Here, we show that solid-state17O NMR spectroscopy can provide unique information about the energy required to break a LBHB. Our solid-state17O NMR data show that the HB enthalpy of the O⋅⋅⋅H⋅⋅⋅N LBHB formed in crystalline nicotinic acid is only 7.7±0.5 kcal mol-1, suggesting that not all LBHBs are particularly strong.
authors.affiliation: Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, K7L 3N6, Canada.
authors.forename: Jiasheng
authors.initials: J
authors.lastname: Lu
authors.affiliation: Center of Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL, 32310, USA.
authors.forename: Ivan
authors.initials: I
authors.lastname: Hung
authors.affiliation: Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, Ontario, K1A 0R6, Canada.
authors.forename: Andreas
authors.initials: A
authors.lastname: Brinkmann
authors.affiliation: Center of Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL, 32310, USA.
authors.forename: Zhehong
authors.initials: Z
authors.lastname: Gan
authors.affiliation: Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, K7L 3N6, Canada.
authors.forename: Xianqi
authors.initials: X
authors.lastname: Kong
authors.affiliation: Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, K7L 3N6, Canada.
authors.forename: Gang
authors.initials: G
authors.lastname: Wu
keywords: energetics; low-barrier hydrogen bonds; molecular motion; oxygen; solid-state NMR spectroscopy