Disordered Crystal Structure and Anomalously High Solubility of Radium Carbonate.

ABSTRACT: Radium-226 carbonate was synthesized from radium-barium sulfate (²²⁶Ra_0.76Ba_0.24SO₄) at room temperature and characterized by X-ray powder diffraction (XRPD) and extended X-ray absorption fine structure (EXAFS) techniques. XRPD revealed that fractional crystallization occurred and that two phases were formed─the major Ra-rich phase, Ra(Ba)CO₃, and a minor Ba-rich phase, Ba(Ra)CO₃, crystallizing in the orthorhombic space group Pnma (no. 62) that is isostructural with witherite (BaCO₃) but with slightly larger unit cell dimensions. Direct-space ab initio modeling shows that the carbonate oxygens in the major Ra(Ba)CO₃ phase are highly disordered. The solubility of the synthesized major Ra(Ba

SUBMITTER: Matyskin AV 

PROVIDER: S-EPMC10394661 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature