Resonant ion–dip infrared spectroscopy (RIDIRS) is used to record clustersize-specific spectra of C₆H₆–(H₂O)_n(BW_n) clusters with n= 1–7 in the C—H and O—H stretch regions (2900–4000 cm^–1). The Fermi triad characteristic of benzene in the C—H stretch region is virtually unchanged by addition of as many as seven water molecules. By contrast, the O—H stretch spectra show a dramatic dependence on cluster size. In C₆H₆–H₂O, the O—H stretch transitions are complicated by additional structure due to internal rotation of H₂O in the complex. In C₆H₆–(H₂O)₂, the O—H stretch spectrum closely mimics that of the free water dimer. For the n= 3–5 clusters, the spectra can be divided roughly into three categories, due to free O—H (3715 cm^–1), π H-bonded O—H (3650 cm^–1), and single donor O—H stretches, consistent with a BW_n structure composed of a cyclic W_n cluster in which one of the free O—H groups is used in π hydrogen bonding with benzene. At n= 6, the spectra show distinct new transitions in the 3500–3600 cm^–1 region. By comparing with the predictions of ab initio calculations of W_n, these new transitions are assigned to double donor O—H stretches associated with the formation of a more compact, ice-like structure in W₆. The transformation to double-donating waters continues to develop in BW₇, where additional transitions in the double-donor O—H stretch region appear at the expense of free O—H transition intensity.