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The structure and vibrational spectroscopy of centrohexaindane, 1, was investigated. This unusual molecule has a quaternary carbon atom that is coordinated to four further such quaternary carbon atoms as its core, each pair of which is bonded to an ortho‐phenylene unit. Previous NMR studies have shown that the molecule has tetrahedral (Td) symmetry in solution. The infrared and Raman spectra of chloroform and deuterochloroform solutions of 1 are completely in agreement with this conclusion, as the only modes that are visible are those allowed for Td symmetry. This is not the case in the solid state: X‐ray powder diffraction indicates that the unit cell is triclinic or monoclinic with a volume in excess of 4000 Å3. The vibrational spectroscopy is consistent with C1 site symmetry and the presence of at least two molecules in the primitive cell. It is likely that the space group is centrosymmetric. [ABSTRACT FROM AUTHOR]

We report reversible high capacity adsorption of SO2 in robust Zr‐based metal–organic framework (MOF) materials. Zr‐bptc (H4bptc=biphenyl‐3,3′,5,5′‐tetracarboxylic acid) shows a high SO2 uptake of 6.2 mmol g−1 at 0.1 bar and 298 K, reflecting excellent capture capability and removal of SO2 at low concentration (2500 ppm). Dynamic breakthrough experiments confirm that the introduction of amine, atomically‐dispersed CuII or heteroatomic sulphur sites into the pores enhance the capture of SO2 at low concentrations. The captured SO2 can be converted quantitatively to a pharmaceutical intermediate, aryl N‐aminosulfonamide, thus converting waste to chemical values. In situ X‐ray diffraction, infrared micro‐spectroscopy and inelastic neutron scattering enable the visualisation of the binding domains of adsorbed SO2 molecules and host–guest binding dynamics in these materials at the atomic level. Refinement of the pore environment plays a critical role in designing efficient sorbent materials. [ABSTRACT FROM AUTHOR]