Mild hydrothermal synthesis, crystal structure, thermal behaviour, spectroscopic and magnetic properties of (NH{sub 4}){sub 0.80}Li{sub 0.20}[Fe(AsO{sub 4})F]

Journal Article · Sat Oct 15 04:00:00 EDT 2011 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.07.043· OSTI ID:21580013

Berrocal, Teresa ^[1]; Mesa, Jose L ^[2]; Larrea, Edurne S; Bazan, Begona; Pizarro, Jose L ^[1]; Lezama, Luis; Rojo, Teofilo ^[2]

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1. Departamento de Mineralogia y Petrologia, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco, UPV/EHU, Apdo. 644, 48080 Bilbao (Spain)
2. Departamento de Quimica Inorganica, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco, UPV/EHU, Apdo. 644, 48080 Bilbao (Spain)

The (NH{sub 4}){sub 0.80}Li{sub 0.20}[Fe(AsO{sub 4})F] compound has been synthesized under mild hydrothermal conditions. The compound crystallize in the orthorhombic Pna2{sub 1} space group, with cell parameters a=13.352(9), b=6.7049(9), c=10.943(2) A and Z=8. The compound belongs to the KTiO(PO{sub 4}) structure type, with chains alternating FeO{sub 4}F{sub 2} octahedra and AsO{sub 4} tetrahedra, respectively, running along the 'a' and 'b' crystallographic axes. The diffuse reflectance spectrum in the visible region shows the forbidden electronic transitions characteristic of the Fe(III) d{sup 5}-high spin cation in slightly distorted octahedral geometry. The Moessbauer spectrum at room temperature is characteristic of iron (III) cations. The ESR spectra, carried out from room temperature to 200 K, remain isotropic with variation in temperature; the g-value being 1.99(1). Magnetic measurements indicate the predominance of strong antiferromagnetic interactions. - Graphical Abstract: Three-dimensional structure of (NH{sub 4}){sub 0.80}Li{sub 0.20}[Fe(AsO{sub 4})F], a fluoroarsenate containing lithium and ammonium in the structural cavities. Highlights: > (NH{sub 4}){sub 0.80}Li{sub 0.20}[Fe(AsO{sub 4})F] has been synthesized by mild hydrothermal technique. > The compound exhibits a three-dimensional structure. > Moessbauer spectrum indicates the existence of Fe(III) cations. > Visible spectroscopy confirms the hexacoordination of Fe(III). > Magnetic measurements indicate the existence of a global antiferromagnetic ordering.

• OSTI ID: 21580013
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 10 Vol. 184; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ANTIFERROMAGNETISM
ARSENATES
ARSENIC COMPOUNDS
CATIONS
CHARGED PARTICLES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALLOGRAPHY
ELECTRON SPIN RESONANCE
HYDROTHERMAL SYNTHESIS
INTERACTIONS
IONS
MAGNETIC PROPERTIES
MAGNETIC RESONANCE
MAGNETISM
MOESSBAUER EFFECT
ORTHORHOMBIC LATTICES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RESONANCE
SPACE GROUPS
SPECTROSCOPY
SYMMETRY GROUPS
SYNTHESIS
THERMAL ANALYSIS
THREE-DIMENSIONAL CALCULATIONS