Crystal structure, magnetic susceptibility and Mössbauer spectroscopy of the mixed-valence iron phosphate Na1/2Cu4/3Fe2(PO4)3
Langue
en
Article de revue
Ce document a été publié dans
Journal of Solid State Chemistry. 2006, vol. 179, n° 6, p. 1808-1813
Elsevier
Résumé en anglais
Single crystals of a new mixed-valent iron phosphate Na1/2Cu4/3Fe2(PO4)3 have been synthesized by a flux method and structurally characterized from X-ray diffraction data: Pl; a= 6.2882(1)A; b=8.0459(1)A; c=9.3255(1)A; ...Lire la suite >
Single crystals of a new mixed-valent iron phosphate Na1/2Cu4/3Fe2(PO4)3 have been synthesized by a flux method and structurally characterized from X-ray diffraction data: Pl; a= 6.2882(1)A; b=8.0459(1)A; c=9.3255(1)A; alpha=105.881(1)°; beta=107.202(1)°; gamma=101.467(1)°; Z = 2 ; R1 = 0.03; wR2=0.093. The three-dimensional structure was found to be closely related to that of the well known Howardevansite structural type. It results from infinite chains of CuO5 and FeO6 polyhedra, joined together by (Cu,square, open)O6 octahedra and PO4 tetrahedra by corner-sharing. The large cavities in framework are occupied by Na+ ions. The magnetic susceptibility study revealed an antiferromagnetic behavior with Neel temperature of approximately 40 K. The Mössbauer spectroscopy confirmed the presence of iron in both +2 and +3 oxidation states.< Réduire
Mots clés en anglais
Phosphate
X-ray diffraction
Howardevansite
Magnetic measurements
Mössbauer spectroscopy
Origine
Importé de halUnités de recherche