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Title: Magnetostructural correlations in the antiferromagnetic Co{sub 2-x} Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) phases

Abstract

The Co{sub 2-x}Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) compounds have been synthesized under mild hydrothermal conditions and characterized by X-ray single-crystal diffraction and spectroscopic data. The hydroxi-arsenate phases crystallize in the Pnnm orthorhombic space group with Z=4 and the unit-cell parameters are a=8.277(2) A, b=8.559(2) A, c=6.039(1) A and a=8.316(1) A, b=8.523(2) A, c=6.047(1) A for x=0 and 0.3, respectively. The crystal structure consists of a three-dimensional framework in which M(1)O{sub 5}-trigonal bipyramid dimers and M(2)O{sub 6}-octahedral chains (M=Co and Cu) are present. Co{sub 2}(OH)AsO{sub 4} shows an anomalous three-dimensional antiferromagnetic ordering influenced by the magnetic field below 21 K within the presence of a ferromagnetic component below the ordering temperature. When Co{sup 2+} is partially substituted by Cu{sup 2+}ions, Co{sub 1.7}Cu{sub 0.3}(OH)AsO{sub 4}, the ferromagnetic component observed in Co{sub 2}(OH)AsO{sub 4} disappears and the antiferromagnetic order is maintained in the entire temperature range. Heat capacity measurements show an unusual magnetic field dependence of the antiferromagnetic transitions. This {lambda}-type anomaly associated to the three-dimensional antiferromagnetic ordering grows with the magnetic field and becomes better defined as observed in the non-substituted phase. These results are attributed to the presence of the unpaired electron in the dx{sup 2}-y{sup 2} orbital and themore » absence of overlap between neighbour ions. - Graphical abstract: Schematic drawing of the Co{sub 2-x}Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) crystal structure view along the |0 1 0| direction. Polyhedra are occupied by the M(II) ions (M=Co and Cu) and the AsO{sub 4} groups are represented by tetrahedra. Open circles correspond to the oxygen atoms, and small circles show the hydrogen atoms. Highlights: > Synthesis of a new adamite-type compound, Co{sub 1.7}Cu{sub 0.3}(OH)AsO{sub 4}. > Single crystal structure, spectroscopic characterization and magnetic properties. > Unusual dependence on the magnetic field for antiferromagnetic transitions. > Incommensurate magnetic structure at low temperature. > Magnetostructural correlations in cobalt-based M{sub 2}(OH)XO{sub 4} (M=Co and Cu) insulation compounds.« less

Authors:
 [1];  [2];  [3];  [2];  [1]
  1. Departamento de Quimica Inorganica, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco UPV/EHU, 48080 Bilbao (Spain)
  2. Departamento de Mineralogia y Petrologia, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco UPV/EHU, 48080 Bilbao (Spain)
  3. CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander (Spain)
Publication Date:
OSTI Identifier:
21580202
Resource Type:
Journal Article
Journal Name:
Journal of Solid State Chemistry
Additional Journal Information:
Journal Volume: 184; Journal Issue: 8; Other Information: DOI: 10.1016/j.jssc.2011.05.060; PII: S0022-4596(11)00309-4; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Journal ID: ISSN 0022-4596
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ANTIFERROMAGNETISM; ARSENATES; CARBON DIOXIDE; COBALT IONS; COPPER IONS; MAGNETIC FIELDS; MAGNETIC PROPERTIES; MONOCRYSTALS; ORTHORHOMBIC LATTICES; SPACE GROUPS; SPECIFIC HEAT; TEMPERATURE RANGE 0065-0273 K; X-RAY DIFFRACTION; ARSENIC COMPOUNDS; CARBON COMPOUNDS; CARBON OXIDES; CHALCOGENIDES; CHARGED PARTICLES; COHERENT SCATTERING; CRYSTAL LATTICES; CRYSTAL STRUCTURE; CRYSTALS; DIFFRACTION; IONS; MAGNETISM; OXIDES; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; SCATTERING; SYMMETRY GROUPS; TEMPERATURE RANGE; THERMODYNAMIC PROPERTIES

Citation Formats

Pedro, I. de, E-mail: depedrovm@unican.es, CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, Rojo, J M, Pizarro, J L, Rodriguez Fernandez, J, Arriortua, M I, and Rojo, T. Magnetostructural correlations in the antiferromagnetic Co{sub 2-x} Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) phases. United States: N. p., 2011. Web. doi:10.1016/j.jssc.2011.05.060.
Pedro, I. de, E-mail: depedrovm@unican.es, CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, Rojo, J M, Pizarro, J L, Rodriguez Fernandez, J, Arriortua, M I, & Rojo, T. Magnetostructural correlations in the antiferromagnetic Co{sub 2-x} Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) phases. United States. doi:10.1016/j.jssc.2011.05.060.
Pedro, I. de, E-mail: depedrovm@unican.es, CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, Rojo, J M, Pizarro, J L, Rodriguez Fernandez, J, Arriortua, M I, and Rojo, T. Mon . "Magnetostructural correlations in the antiferromagnetic Co{sub 2-x} Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) phases". United States. doi:10.1016/j.jssc.2011.05.060.
@article{osti_21580202,
title = {Magnetostructural correlations in the antiferromagnetic Co{sub 2-x} Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) phases},
author = {Pedro, I. de, E-mail: depedrovm@unican.es and CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander and Rojo, J M and Pizarro, J L and Rodriguez Fernandez, J and Arriortua, M I and Rojo, T},
abstractNote = {The Co{sub 2-x}Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) compounds have been synthesized under mild hydrothermal conditions and characterized by X-ray single-crystal diffraction and spectroscopic data. The hydroxi-arsenate phases crystallize in the Pnnm orthorhombic space group with Z=4 and the unit-cell parameters are a=8.277(2) A, b=8.559(2) A, c=6.039(1) A and a=8.316(1) A, b=8.523(2) A, c=6.047(1) A for x=0 and 0.3, respectively. The crystal structure consists of a three-dimensional framework in which M(1)O{sub 5}-trigonal bipyramid dimers and M(2)O{sub 6}-octahedral chains (M=Co and Cu) are present. Co{sub 2}(OH)AsO{sub 4} shows an anomalous three-dimensional antiferromagnetic ordering influenced by the magnetic field below 21 K within the presence of a ferromagnetic component below the ordering temperature. When Co{sup 2+} is partially substituted by Cu{sup 2+}ions, Co{sub 1.7}Cu{sub 0.3}(OH)AsO{sub 4}, the ferromagnetic component observed in Co{sub 2}(OH)AsO{sub 4} disappears and the antiferromagnetic order is maintained in the entire temperature range. Heat capacity measurements show an unusual magnetic field dependence of the antiferromagnetic transitions. This {lambda}-type anomaly associated to the three-dimensional antiferromagnetic ordering grows with the magnetic field and becomes better defined as observed in the non-substituted phase. These results are attributed to the presence of the unpaired electron in the dx{sup 2}-y{sup 2} orbital and the absence of overlap between neighbour ions. - Graphical abstract: Schematic drawing of the Co{sub 2-x}Cu{sub x}(OH)AsO{sub 4} (x=0 and 0.3) crystal structure view along the |0 1 0| direction. Polyhedra are occupied by the M(II) ions (M=Co and Cu) and the AsO{sub 4} groups are represented by tetrahedra. Open circles correspond to the oxygen atoms, and small circles show the hydrogen atoms. Highlights: > Synthesis of a new adamite-type compound, Co{sub 1.7}Cu{sub 0.3}(OH)AsO{sub 4}. > Single crystal structure, spectroscopic characterization and magnetic properties. > Unusual dependence on the magnetic field for antiferromagnetic transitions. > Incommensurate magnetic structure at low temperature. > Magnetostructural correlations in cobalt-based M{sub 2}(OH)XO{sub 4} (M=Co and Cu) insulation compounds.},
doi = {10.1016/j.jssc.2011.05.060},
journal = {Journal of Solid State Chemistry},
issn = {0022-4596},
number = 8,
volume = 184,
place = {United States},
year = {2011},
month = {8}
}