Density functional study of the hydrogen bonding: H2O·HO

Density functional theory was used to study the hydrogen bonding between the water molecule and the hydroxyl radical. The two energetically low-lying minima are 1 (2A′) and 2 (2A″), with hydrogen bonding occurring between the oxygen atom of H2O and the hydrogen atom of the OH radical. Another hydrogen bond (3, 2A″) occurs between one of the hydrogen atoms of H2O and the oxygen atom of OH. The interaction energies for various isomers were calculated at the UB3LYP, UMP2 and CCSD(T) levels. The infrared spectra and the vibrational frequency shifts are also reported.