Rotational Displacement of IO_4 Tetrahedron in the Phase II of Pyridinium Periodate

Rotational Displacement of IO_4 Tetrahedron in the Phase II of Pyridinium Periodate

Creators Miyoshi Tatsuki

Creators Kasano Hironobu

Creators Mashiyama Hiroyuki

In order to investigate the displacement of the IO_4 tetrahedron in the ferroelectric phase II of pyridinium periodate in detail, we performed X-ray structural analysis at 33 temperatures with the use of the estimated site occupancies of carbon and nitrogen atoms. We confirmed the continuous increase of the rotation angle of the IO_4 tetrahedron about the a^-axis with decreasing temperature in the phase II. This indicates that the IO_4 tetrahedron acts as the displacive structural unit at the transition from phase I to phase II. It is found that the rotation of the IO_4 tetrahedron is correlated with the reorientation of the pyridinium cation through the N-H O type hydrogen bond.

[ISSN]0015-0193

[NCID]AA00644949

info:doi/10.1080/00150190601182006

[isVersionOf] [URI]http://www.tandf.co.uk/journals/titles/00150193.asp