The solid-state synchronous vs. conventional fluorescence spectroscopy and complementary methods to study the interactions of aluminum metal-organic framework Basolite A100 with dimethyl sulfoxide

We report, for the first time, an experimental study of interaction of metal-organic framework (MOF) with dimethyl sulfoxide (DMSO). Adsorption of DMSO on aluminum MOF Basolite A100 results in formation of the stoichiometric complex [A100](2)[DMSO](3). The solid-state synchronous fluorescence spectroscopy allows observation of the following major excitation/emission transitions in Basolite A100 and its adsorption complex [A100](2)[DMSO](3) which are not well-resolved in conventional fluorescence spectra: 1) narrow resonance of the isolated BDC linker, 2) excitation across optical bandgap, and 3) excimers. In the adsorption complex [A100](2)[DMSO](3), the DMSO molecules interact with the mu(2)-OH group of Basolite A100 and with its BDC linker through the p-p system. We present, for the first time, the new variety of the solid-state synchronous fluorescence spectroscopy, which we denote as the solid-state enhanced-resolution synchronous fluorescence (excitation) spectroscopy. The accurate measurements of small changes in the optical bandgap of the adsorption complex [A100](2)[DMSO](3) and Basolite A100 are described by the solid-state enhanced-resolution synchronous fluorescence (excitation) spectroscopy.