Preparation and Characterization of a New 3-Dimensional Zirconium Hydrogen Phosphate, τ-Zr(HPO4)2; Determination of the Complete Crystal Structure Combining Synchrotron X-ray Single Crystal Diffraction and Neutron Powder Diffraction.

• A new 3-dimensional zirconium hydrogen phosphate, τ-Zr(HPO4)2, was prepared by hydrothermal syntheses. The preparation, characterization, and determination of the crystal structure of this new material are reported. The structure was solved from single-crystal synchrotron diffraction on a 25 × 25 × 50 μm crystal. The position of the hydrogen atom was found using high-resolution neutron powder diffraction data. The unit cell is tetragonal, space group I41cd (No. 110), with lattice parameters a = 11.259(1) Å, c = 10.764(1) Å, and Z = 8. The structure can be described as a 3-dimensional framework built from ZrO6 octahedra bound together by hydrogen phosphate groups (PO3(OH)). The OH groups form a hydrogen-bonded spiral along the 41 axes, with each hydrogen phosphate both donating and accepting hydrogen bonds. The thermal transformations of τ-Zr(HPO4)2 were studied using in-situ temperature-resolved powder diffraction experiments. Hereby the existence of two new phases was discovered. The new phases have been indexed and the unit cell parameters are as follows. Intermediate I:  a = 8.172(1), b = 7.691(1), and c = 10.794(2) Å. Intermediate II: a = 8.283(2), b = 6.620(2), and c = 10.643(2) Å.

Subject headings

NATURVETENSKAP  -- Kemi -- Oorganisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Inorganic Chemistry (hsv//eng)

Keyword

Inorganic chemistry

Oorganisk kemi

Publication and Content Type

ref (subject category)

art (subject category)