Crystal structure, magnetic susceptibility and Mössbauer spectroscopy of the mixed-valence iron phosphate Na1/2Cu4/3Fe2(PO4)3
Language
en
Article de revue
This item was published in
Journal of Solid State Chemistry. 2006, vol. 179, n° 6, p. 1808-1813
Elsevier
English Abstract
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; ...Read more >
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.Read less <
English Keywords
Phosphate
X-ray diffraction
Howardevansite
Magnetic measurements
Mössbauer spectroscopy
Origin
Hal imported