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Updated: May 20, 2026
11:32
High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
A novel crystal polymorph of volborthite, Cu3V2O7(OH)2·2H2O
Hajime Ishikawa1, Jun-ichi Yamaura, Yoshihiko Okamoto
1Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa 277-8581, Japan. ishikawa@issp.u-tokyo.ac.jp
Summary
A new crystal structure of tricopper(II) divanadium(V) heptaoxide dihydroxide dihydrate (volborthite) was synthesized. This monoclinic polymorph, identified via X-ray analysis, differs from the previously known structure and may influence magnetic properties.
Area of Science:
- Mineralogy
- Crystallography
- Solid-state chemistry
Background:
- Volborthite, Cu(3)V(2)O(7)(OH)(2)·2H(2)O, is a mineral containing copper and vanadium.
- Previous studies identified a C2/m crystal structure for volborthite.
Purpose of the Study:
- To synthesize and characterize a new polymorph of volborthite.
- To investigate the crystallographic differences between the new and previously reported structures.
Main Methods:
- Hydrothermal synthesis of single crystals.
- X-ray diffraction analysis to determine crystal structure and space group.
Main Results:
- A new monoclinic polymorph of volborthite with space group C2/c was successfully synthesized.
- The new structure exhibits distinct crystallographic features compared to the previously reported C2/m structure.
- Both structures share Cu(3)O(6)(OH)(2) layers with V(2)O(7) pillars, but differ in the number of independent crystallographic sites for Cu atoms.
Conclusions:
- The discovery of a new volborthite polymorph expands the understanding of its structural diversity.
- Differences in crystallographic sites may lead to varied magnetic interactions within the kagome lattices of the two volborthite structures.
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