Hydrogen Delocalization in an Asymmetric Biomolecule: The Curious Case of Alpha-Fenchol.

ABSTRACT: Rotational microwave jet spectroscopy studies of the monoterpenol α-fenchol have so far failed to identify its second most stable torsional conformer, despite computational predictions that it is only very slightly higher in energy than the global minimum. Vibrational FTIR and Raman jet spectroscopy investigations reveal unusually complex OH and OD stretching spectra compared to other alcohols. Via modeling of the torsional states, observed spectral splittings are explained by delocalization of the hydroxy hydrogen atom through quantum tunneling between the two non-equivalent but accidentally near-degenerate conformers separated by a low and narrow barrier. The energy differences between the torsional states are determined to be only 16(1) and 7(1) cm-1hc for the protiated and deuterated a

SUBMITTER: Medel R 

PROVIDER: S-EPMC8746872 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature