Ordering Phase Transition with Symmetry-Breaking from Disorder over Non-Equivalent Sites: Calorimetric and Crystallographic Study of Crystalline <span style="font-variant: small-caps;">d</span>-Sorbose

oleh: Sakiko Iwagaki, Hiroki Kakuta, Yasuhisa Yamamura, Hideki Saitoh, Mafumi Hishida, Kazuhiro Fukada, Kazuya Saito

Format: Article
Diterbitkan: MDPI AG 2020-05-01

Deskripsi

Phase transitions in the crystalline state of chiral sorbose were examined using precise heat capacity calorimetry and X-ray crystallography. The calorimetry established heat capacity below room temperature. Besides the known transition (main transition) at 199.5 K, the calorimetry detected plural thermal anomalies assignable to new phase transitions (around 210 K) and a glass transition (at ca. 120 K). The X-ray diffraction at low temperatures established the crystal structure of the lowest temperature phase. The identification of the broken symmetry upon the main transition solves an apparent contradiction that the structural disorder reported previously does not contribute seemingly to the symmetrization.