Fig. 6. Photographic images of (a) Cu4@oCBT and (b) Cu4@mCBT clusters show visible luminescence changes from green to yellow upon mechanical grinding. Luminescence was regenerated upon exposure of vapours of DCM. (c) Cu4@ICBT shows unaltered mechanoresponsive behaviour. Photoluminescence spectra of the grinding-solvent exposure cycle of (d) Cu4@oCBT, (e) Cu4@mCBT and (f) Cu4@ICBT. PXRD spectra of (g) Cu4@oCBT, (h) Cu4@mCBT and (i) Cu4@ICBT reveal a reduction of crystallinity upon grinding and regenerating the crystallinity upon solvent exposure.
