Stretchable Tb-Tb Distance Regulates the Piezofluorochromic Behavior of Chiral Tb(III)-MOF upon Compression.

Luminescent chiral microcrystals with the Tb(COO) subunit indicated strong green mechano-luminescence under compression. Furthermore, piezofluorochromic behavior in the diamond anvil cell was observed, with the intensity tendency of decreasing-increasing-decreasing and a shortened lifetime upon compression, due to the reversible stretchable Tb-Tb interactions. The Tb-Tb distance upon compression was refined through situ high-pressure X-ray absorption spectra, which was consistent with the tendency of the piezofluorochromic intensity. high-pressure UV-vis absorption spectra, Fourier transform infrared spectra, and powder X-ray diffraction demonstrated the full recovery of after over 10 GPa compressions due to the semiflexible ligand. This work not only provided an ultrastable but also illustrated the relationship of the piezofluorochromic behavior with the detailed structural transformation for the first time.