Syntheses and characterization of non-molecular phenyl- and methyl-phosphonates and ethylenediphosphonates of thorium and cerium

Abstract

Eight non-molecular phenyl- and methyl-phosphonates and ethylenediphosphonates of thorium and cerium, namely, Th(O₃PC₆H₅)₂·H₂O (1), Th(O₃PCH₃)₂·H₂O (2), Th(O₃P(CH₂)₂PO₃)·H₂O (3), Ce(O₃PCH₃)(HO₃PCH₃) (4), Ce(O₃P(CH₂)₂PO₃H) (5), Th(O₃PCH₃)F₂ (6), Th(O₃P(CH₂)₂PO₃H)F·H₂O (7), and Ce(HO₃PCH₃)₂F₂ (8), were synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction, spectroscopic, thermal and magnetic susceptibility studies. They have layered, pillared-layered and one-dimensional structures containing 7–9 coordinated metal ions. The ³¹P and ¹³C solid-state MAS NMR spectroscopic data of compounds 1–5 are in accordance with their single-crystal X-ray structures. The compounds 1–3 lose their water of crystallization at temperatures as low as 60 °C while the compounds 4–6 and 8 remain stable up to at least 270 °C. The magnetic susceptibility measurements of compounds 4 and 5 corroborate the Ce³⁺ oxidation state.