In a mixed experimental/computational study, DFT using PBCs was used to study the pressureinduced ovalization and aggregation of the [6]cycloparaphenylene ([6]CPP) nanohoop and the resulting Raman spectra. Pressure was observed to cause a blue shift of most Raman modes, but a sudden change in the Raman spectrum was observed at a certain threshold pressure, which was interpreted as a sign of the formation of intermolecular σ bonds on the basis of the DFT calculations. As in many other studies, pressure led to a broadening of Raman modes and to the split of some signals, due to a loss of symmetry in the crystal.