X-ray structure analyses of chloranil above and below phase transition temperature

Y. Kubozono, T. Yoshida, H. Maeda, S. Kashino, H. Terauchi, T. Ishii

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


The crystal structure of chloranil above and below the phase transition temperature, Tc (= 90 K), has been studied by single crystal X-ray diffraction at 20, 40, 60, 70, 80, 85, 90, 95, 100, 110, 130, and 150 K. Below Tc the difference, Δφ, between the angle of an a axis and an O...O vector in a chloranil molecule [projected to (010) plane] at any temperature and the angle at Tc increases with a power law relation with a decrease in temperature. It shows that the Δφ is an order parameter. It has been found that the mean-square-displacements of O and Cl atoms increase around Tc. The intermolecular nearest O...C distance decreases with a decrease in temperature above Tc. However, it splits into two types below Tc, and their mean value does not decrease with a decrease in temperature. We have concluded that two types of molecular rotations of clockwise and counterclockwise for neighboring molecules induce this phase transition to avoid too small O...C distance below 90 K.

Original languageEnglish
Pages (from-to)1375-1381
Number of pages7
JournalJournal of Physics and Chemistry of Solids
Issue number9
Publication statusPublished - Sept 1997


  • C. X-ray diffraction
  • D. crystal structure
  • D. phase transition

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics


Dive into the research topics of 'X-ray structure analyses of chloranil above and below phase transition temperature'. Together they form a unique fingerprint.

Cite this