A quick appraisal of the low-energy candidate structures establishes the presence of the bisulfate-bisulfate hydrogen bond in all four structures. Structures A, B, and D reproduce the relative intensity pattern of the carbonyl stretching mode. Of these, we find that the relative intensities of the bisulfate-specific modes below 1000 cm -1 are well reproduced in structure A's spectrum while the spectra of B and D display more complexity in this region. Thus, the similarity between the experimental spectrum and the calculated spectrum suggests that structure A is the experimentally probed structure of the (G) 3 (A) 0 (SA) 2 cluster.