AbstractFour different picotubes have been synthesized up to now. These highly symmetric, ringlike hydrocarbons are closely related to the smallest armchair nanotubes available. We investigate vibrational properties of the different picotubes using first principles calculations and polarization‐dependent Raman spectroscopy. Our results emphasize the strong relationship between picotubes and nanotubes.In this context, two features in the picotube spectra are of particular interest: The high‐energy bands and breathing‐like modes. Vibrational patterns calculated for the high‐energy modes of picotubes are similar to the axial and transversal high‐energy vibrations of armchair nanotubes. Concerning the radial breathing modes of picotubes, our calculations suggest a d–1‐dependence of the radial breathing mode (RBM) frequency, which is again in analogy to nanotubes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)