An infrared spectroscopic study of trifluoromethoxybenzeneMIDLINE HORIZONTAL ELLIPSISmethanol complexes formed in superfluid helium nanodroplets

We have studied the intermolecular complex formation between trifluoromethoxybenzene and methanol (CD3OD) in superfluid helium droplets by infrared spectroscopy in the spectral range of 2630-2730 cm(-1), covering the O-D stretches of methanol-d(4) (CD3OD). The cluster size associated with the observed bands is deduced from the variation of infrared intensity of a particular band with the partial pressures of trifluoromethoxybenzene and methanol. Quantum chemical calculations are performed at the MP2/6-311++G(d,p) level of theory to complement the experimental results. As a result, we have identified six different conformers of the trifluoromethoxybenzeneMIDLINE HORIZONTAL ELLIPSISmethanol intermolecular complex: three bound via O-HMIDLINE HORIZONTAL ELLIPSISO hydrogen bonds and the other three via O-HMIDLINE HORIZONTAL ELLIPSIS pi hydrogen bonds. Furthermore, to access the effect of fluorination on the methyl unit of anisole molecules, we compare the IR spectrum of trifluoromethoxybenzene (C6H5OCF3)MIDLINE HORIZONTAL ELLIPSISmethanol with our earlier reported spectrum of anisole (C6H5OCH3)MIDLINE HORIZONTAL ELLIPSISmethanol.

Automated summary

The study investigated the intermolecular complex formation between trifluoromethoxybenzene and methanol using infrared spectroscopy and quantum chemical calculations. The results identified six different conformers of the complex, with three bound via hydrogen bonds and the other three via pi hydrogen bonds. Additionally, the effect of fluorination on the methyl unit of anisole molecules was compared by analyzing the IR spectrum of trifluoromethoxybenzene-methanol complex.