product, yielding phenylene-modified hybrid mesoporous ethenylenesilica (Ph-HME). The Ph-HME was then sulfonated by heating at 80 C for 3 days in concentrated H 2 SO 4 . The solid was recovered and washed in water at 80 C for 6 h. The washing treatment was repeated twice, and the final product was dried at room temperature to afford Ph±SO 3 H HME.Acid-Catalyzed Reaction: The esterification of acetic acid and pinacol±pinacolone rearrangement were employed as test reactions to examine the acid properties of the prepared samples. Esterification of acetic acid was examined in the liquid phase as follows: 0.20 g of the catalyst was evacuated at 423 K for 1 h and then added to a mixture of acetic acid (0.10 mol) and ethanol (1.0 mol). The reaction was carried out at 343 K in an Ar atmosphere, and the liquid phase was analyzed using gas chromatography with capillary columns. Pinacol± pinacolone rearrangement was performed in the liquid phase as follows: 0.20 g of the catalyst was evacuated at 423 K for 1 h and then added to pinacol (42.3 mol) without the addition of solvent. The reaction was carried out at 403 K in an Ar atmosphere, and the liquid phase was analyzed using gas chromatography with capillary columns.Measurement: Nitrogen adsorption±desorption isotherms were measured at 77 K using a Micrometrics Coulter SA-3100 system. Prior to measurement, the samples were pretreated at 423 K for 3 h under vacuum to a final pressure of 1 10 ±5 torr (1 torr = 133 Pa). The Brunauer±Emmett±Teller (BET) surface area was estimated over a relative pressure (P/P 0 ) range of 0.05±0.30. The pore size distribution was obtained from an analysis of the adsorption branch of the isotherms using the Barrett±Joyner±Halenda (BJH) method. Solid-state 13 C and 29 Si CP-MAS NMR measurements were acquired on Bruker ASX200 and ASX400 spectrometers, respectively. The Larmor frequencies for 13 C and 29 Si were 50.3 and 79.5 MHz, respectively. The experimental parameters were as follows.13 C CP-MAS NMR: 4.0 kHz spin rate, 5 s recycle delay, 2 ms contact time, and 4.0 ls p/2 pulse width.29 Si CP-MAS NMR experiment: 4.0 kHz spin rate, 5 s recycle delay, 5 ms contact time, 5.9 ls p/2 pulse width. The chemical shifts of 13 C and 29 Si spectra were expressed with respect to neat tetramethylsilane.

The relaxation dynamics of water in hygroscopic molecular solids is probed by broadband dielectric spectroscopy in the temperature range from 200 to 450 K. Evidence is found for three types of dynamic processes. The intermediate process is common to all probed materials and is associated with the reorientation of bound water molecules that are attached directly onto organic molecules and counterions. A faster process is observed in rhodamine chloride and fullerol, which is the dynamic signature of water in higher hydration layers, either at grain boundaries (rhodamine) or in interstitial clusters (fullerol). All these processes are observed near room temperature and exhibit nonmonotonic temperature dependence and decreasing spectral strength upon heating. In fullerol a third, ultraslow relaxation is observed at high temperature, which may be due to the reorientation of water–fullerol complexes or to the diffusion of water vapor through intermolecular voids.

The polymorphism and the dynamics of a simple rigid molecule (1-fluoro-adamantane) have been studied by means of xray powder diffraction and broadband dielectric spectroscopy. At temperatures below the melting, the molecule forms an orientationally disordered phase I with cubic-centered structure (Phase I, Fm 3 m, Z=4). This phase possesses eight equilibrium positions for the fluorine atom, with equal occupancies factors of 1/8. A solid-solid phase transition to a lowtemperature tetragonal phase (Phase II, P 4 21c, Z=2) reduces the statistical disorder to only four possible equivalent sites for the fluorine atom, with fractional occupancies of 1/4. The dynamics has been rationalized under the constraints imposed by the space group of the crystal structure determined by powder X-ray diffraction. The dielectric spectroscopy study reveals that the statistical disorder in Phase II is dynamic in character and is associated with reorientational jumps along the two-and three-fold axes. In the dielectric loss spectra, the cooperative (α) relaxation exhibits a shoulder on the high-frequency side. This remarkable finding clearly reveals the existence of two intrinsic reorientational processes associated with the exchange of the F atom along the four sites. In addition to such "bimodal" relaxation, a secondary Johari-Goldstein relaxation is detected at lower temperatures.

Impedance spectroscopy is employed to probe the frequency-dependent conductivity and dielectric response of the C60O24Na24 fulleride. The conduction properties of this organic material match the so-called universal behavior of the ac conductivity in disordered media [Dyre, J. C.; Schroder, T. B. Rev. Mod. Phys. 2000, 72, 873–892]. In the whole temperature range studied, electrical conduction is due to intermolecular hopping processes of electronic charge carriers, characterized by an effective activation energy ranging between 0.7 eV at room temperature and 0.9 eV at 475 K. A single dielectric loss feature is observed, associated with the hopping of charge carriers surrounded by a polarization cloud. The polarizability of the material is mainly due to the distortion of the ionic O–Na bonds of the fullerene derivative, which are tight enough that no ionic contribution to the conductivity is observed up to the highest temperature probed (550 K).