Fullerene-Benzene purple and yellow clusters: Theoretical and experimental studies

•Fullerene-benzene interaction.•Fullerene-benzene purple and yellow complexes.•TD-DFT spectra calculations for purple and yellow complexes.•Vertically arranged 6 benzene molecules around a Fullerene molecule forms purple complex.•Horizontally arranged 6 benzene molecules around a Fullerene molecule forms yellow complex.

Fullerene (FR, C60) gives a purple colored solution almost instantly when benzene is added to it. Interestingly, this purple solution turns yellow in about 7 weeks and remains yellow afterwards. The concentration of the purple complex increases with temperature indicating its formation kinetically favored, which transforms into a more stable yellow complex very slowly with time. The geometry optimization by density functional theory (DFT) followed by spectra (TD-DFT method) calculations suggest that the purple and yellow complexes are due to clusters of six benzene molecules arranged vertically and horizontally respectively around the FR molecule.

Graphical abstractFullerene-Benzene cluster with 6 benzene molecules.Figure optionsDownload full-size imageDownload as PowerPoint slide