UPDATE - Superstructure Formation through Coupled Anion and Cation Ordering in Cu-substituted Lead Oxyapatites

Scheifers, Jan, Richardson, Adam, Lin, Hai, Niu, Hongjun, Daniels, Luke, Gaultois, Michael, Alaria, Jonathan, Robertson, Craig, Claridge, John and Rosseinsky, Matthew (2024) UPDATE - Superstructure Formation through Coupled Anion and Cation Ordering in Cu-substituted Lead Oxyapatites. [Data Collection]

Data Catalogue DOI: 10.17638/datacat.liverpool.ac.uk/2846

Original publication URL: https://pubs.acs.org/doi/10.1021/acs.chemmater.4c0...

Description

UPDATE - Apatites are an important mineral-based materials family with huge chemical and structural diversity. They were recently implicated in the of claims of high temperature superconductivity in materials labelled LK-99 that display complex phase mixtures containing Pb, Cu, phosphate, and oxide components. We report Cu substituted lead apatite solid solutions Pb10-xCux(PO4)6O that display two distinct compositional ranges differentiated by structural ordering. For x > 0.5, we observe substitution in the apatite archetype structure, whereas for x < 0.5, we find a new apatite structure type with coupled anion and cation ordering. The new 1 × 1 × 2 superstructure in the noncentrosymmetric space group P6 ̅ (no. 174) for Pb10-xCux(PO4)6O with x < 0.5 exhibits a unique oxygen ordering motif in the hexagonal channels and selective Cu substitution only on two out of seven Pb-sites. At x > 0.5 in Pb10-xCux(PO4)6O Cu cations are introduced onto all Pb sites which triggers the transition to the archetypical apatite structure , reflecting the coupling of the core structural components of the apatite framework in the ordering pattern .

Keywords:

Crystallography, superconductivity, apatite

Divisions:

Faculty of Science and Engineering > School of Physical Sciences > Chemistry

Depositing User:

Luke Daniels

Date Deposited:

30 Jun 2025 13:09

Last Modified:

30 Jun 2025 13:09

DOI:

10.17638/datacat.liverpool.ac.uk/2846