On the competition between weak O-H•••F and C-H•••F hydrogen bonds, in cooperation with C-H•••O contacts, in the difluoromethane-tert-butyl alcohol cluster

The 1:1 complex of tert-butyl alcohol with difluoromethane has been characterized by means of a joint experimental-computational investigation. Its rotational spectrum has been recorded by using a pulsed jet Fourier-Transform microwave spectrometer. The experimental work has been guided and supported by accurate quantum-chemical calculations. In particular, the computed potential energy landscape pointed out the formation of three stable isomers. However, the very low interconversion barriers explain why only one isomer, showing one O-H center dot center dot center dot F and two C-H center dot center dot center dot O weak hydrogen bonds, has been experimentally characterized. The effect of the H tert-butyl-group substitution has been analyzed from the comparison to the difluoromethane-water adduct. (C) 2017 Elsevier Inc. All rights reserved.