Infrared spectra of Cl−-(C6H6)mm = 1, 2

Infrared spectra of mass-selected Cl−-(C6H6)Ar and Cl−-(C6H6)2 complexes obtained in the CH stretch region. Comparison of the experimental Cl−-(C6H6)2 spectrum with simulated spectra based on MP2/aug-cc-pVDZ calculations suggests that both benzene molecules are attached to the Cl− by double hydrogen bonds.