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 00:00:00 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, Vol. 184, Issue 10; Other Information: DOI: 10.1016/j.jssc.2011.07.043; PII: S0022-4596(11)00422-1; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

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