A new polymorph of anhydrous β-cyclodextrin (polymorph III) was obtained and characterized for the first time using powder X-ray diffraction, infrared spectroscopy and thermal analysis. Solution enthalpy and time of dissolution in water were determined by solution calorimetry for this polymorph and compared with those of dried commercial form of β-cyclodextrin (polymorph I), its amorphous form and 2-hydroxypropyl-β-cyclodextrin. Specific heat capacity of polymorphs I and III was determined by differential scanning calorimetry in the wide range of temperatures, which gives enthalpy and Gibbs energy of polymorphic transition at 298 K. Affinity of polymorph III and 2-hydroxypropyl-β-cyclodextrin for water was characterized by determination of their hydration isotherms, which gives the values of hydration Gibbs energy. Being energy-rich, the found new polymorph of β-cyclodextrin has a significantly higher dissolution rate and an in-creased affinity for water compared with the dried commercial form of β-cyclodextrin. Such properties make the new polymorph promising in industrial applications for guest inclusion in aqueous solutions and pastes and may be a desirable alternative for water-soluble β-cyclodextrin derivatives.

1,3,5-Tris-(α-naphthyl)benzene is an organic non-electrolyte with notable stability of an amorphous phase. Its glassy and supercooled liquid states were previously studied by spectroscopic and calorimetric methods. However, the thermodynamic parameters of phase transitions available from the literature are inconsistent. In this work, the heat capacities of crystalline and liquid phases, the temperature dependence of the saturated vapor pressures, fusion and vaporization enthalpies were determined using differential and fast scanning calorimetry and verified using the estimates based on solution calorimetry. The structural features of 1,3,5-tris-(α-naphthyl)benzene are discussed based on the computations performed and the data on the molecular refractivity. The consistency between the values obtained by independent techniques was demonstrated. The deviations in the previously published data were attributed to possible polymorphism.