AbstractInfrared spectra were obtained for the series of 2,X‐dimethylheptanes (X = 2,3,4,5,6) and were interpreted with the aid of normal coordinate calculations. 2,2‐DMH exists as two conformers, with the Csconformer being the only one present in the crystalline solid. 2,3‐DMH exists in at least three conformations, all of C1symmetry. Ambiguities in spectral data indicate that more conformations are present. Two C1conformations of 2,4‐DMH were shown to be present, but an unassigned band may indicate the presence of a third conformer. The presence of at least four conformers, all of C1symmetry, was shown to be necessary to explain the spectrum of 2,5‐DMH. Finally, 2,6‐DMH was shown to exist as three conformers, of symmetries Cs, C2, and C1. Vibrational assignments were made for all the probable conformers of all fiv