MOLECULE -- please stay -- SOLVED!
Interesting case - several different half ring attachments on a (30,30) armchair nanotube with 15060 C atoms. Nanotube prepared in the same manner as the thinner ones, but longer so it vibrates well.
Frequency was analysed with a MATLAB code that
took Fourier transform, gave a spectrum of resonance frequencies.
Attachments of half rings with 78 atoms each were placed at different places along the tube, see two realizations at left. Graphs of the lowest frequencies in the z direction for different numbers of additional half rings. Despite the differing amplitudes,
We observe a clear trend that the frequency decreases as adsorbed mass increases.