The Cl--(C6H6)Ar-n n = 0, 1, 2 and Cl--(C6H6)(2) Complexes are investigated using photodissociation infrared spectroscopy in the CH stretch region and through ab initio calculations at the MP2/aug-cc-pVDZ level. The results indicate that Cl--C6H6 possesses a planar structure in which the benzene molecule is attached to the Cl-anion by a double hydrogen bond. The calculations predict that Cl--(C6H6)(2) has a C-2 symmetry structure in which the two face-to-face benzene molecules are attached to the Cl- anion by double hydrogen bonds. This structure is compatible with the measured Cl--(C6H6)(2) infrared spectrum. (c) 2006 Elsevier B.V. All rights reserved.