Hydrogen bonding between formic acid and water: complete stabilization of the intrinsically unstable conformer.
We studied hydrogen bonding between formic acid (FA) and water in solid argon and identified the first water complex with the higher-energy conformer cis-FA. In sharp contrast to cis-FA monomer, cis-FA interacting with water is very stable at low temperatures, which was explained by strong O-H...O hydrogen bonding. These benchmark results show that hydrogen bonding can terminate proton tunneling reactions and efficiently stabilize intrinsically unstable conformational structures in complex asymmetrical hydrogen-bonded networks. This general effect occurs when the energy difference between conformers is smaller than the hydrogen bond interaction energy, which opens perspectives in chemistry on intrinsically unstable conformers.
Marushkevich
Kseniya
K
Laboratory of Physical Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki, Finland.
Khriachtchev
Leonid
L
Räsänen
Markku
M
D005561:Formates / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008968:Molecular Conformation; D013055:Spectrophotometry, Infrared; D014867:Water / Q000737:chemistry*
D005561:Formates; D014867:Water; C030544:formic acid