New mesoporous covalent frameworks, based on hybrid fluorinated organosilicas, were prepared to realize a periodic architecture of fast molecular rotors containing dynamic dipoles in their structure. The mobile elements, designed on the basis of fluorinated p-divinylbenzene moieties, were integrated into the robust covalent structure through siloxane bonds, and showed not only the rapid dynamics of the aromatic rings (ca. 10(8) Hz at 325 K), as detected by solid-state NMR spectroscopy, but also a dielectric response typical of a fast dipole reorientation under the stimuli of an applied electric field. Furthermore, the mesochannels are open and accessible to diffusing in gas molecules, and rotor mobility could be individually regulated by I2 vapors. The iodine enters the channels of the periodic structure and reacts with the pivotal double bonds of the divinyl-fluoro-phenylene rotors, affecting their motion and the dielectric properties.

The structure of a synthetic fluoromica has been investigated and elucidated by complementary 29Si, 1H, 19F, 23Na, and 27Al single and double resonance experiments. The phyllosilicate possesses a charge heterogeneity arising from the presence of different charged sites in the octahedral sheets of the T-O-T layers. Part of the magnesium atoms in the octahedral sheets is missing, creating vacancies. Charge balancing proceeds mostly by incorporation of sodium ions into the interlayer space and substitution of Mg by sodium in the lattice. The latter process produces a nonexchangeable fraction of sodium ions (∼20% of the total inventory) and creates multiple sites for the fluoride ions, as evidenced from 19F NMR spectroscopy. Detailed quantitative information about the sodium–fluoride distance geometries were obtained from 19F/23Na double rotational echo double resonance (REDOR) experiments; furthermore, different types of fluoride sites could be discriminated on the basis of 19F/23Na double resonance experiments. The chemical reactivity of this system was modified by ball milling, cation exchange with octadecylammonium ions, and grafting with an organosilane (γ-aminopropyltriethoxysilane), and the corresponding structural consequences were probed by multinuclear single and double resonance NMR techniques.

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