Investigation of the changes in hydrogen bonding accompanying the structural reorganization at 103 K in ammonium iodate

Jones

Abstract

Neutron powder diffraction has been used to observe the changes in hydrogen bonding that occur as a function of temperature in ND4IO3 and, thus, determine the structural features that occur during the low-temperature (103 K) phase transition. It is shown that in the deuterated material the change is not a phase change per se but rather a structural reorganization in which the hydrogen bonding becomes firmly locked in at the phase transition temperature, and stays in this configuration upon further cooling to 4.2 K. In addition, both the differences and changes in the axial thermal expansion coefficients in the region 100–290 K can be explained by the changes involving both the hydrogen bonding and the secondary I?O halogen bonds.

Citation

Jones. (2019). Investigation of the changes in hydrogen bonding accompanying the structural reorganization at 103 K in ammonium iodate. Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials, https://doi.org/10.1107/S2052520619000325

• Acceptance Date: Jan 7, 2019
• Publication Date: Apr 1, 2019
• Journal: Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials
• Print ISSN: 2052-5192
• Publisher: International Union of Crystallography
• DOI: https://doi.org/10.1107/S2052520619000325
• Keywords: neutron diffraction; hydrogen bonding; phase transitions; variable temperature; ammonium ion
• Publisher URL: http://doi.org/10.1107/S2052520619000325