Six novel transition-metal phosphite compounds, with structure related to yavapaiite: Crystal structures and magnetic and thermal properties of A{sup I}[M{sup III}(HPO{sub 3}){sub 2}] (A=K, NH{sub 4}, Rb and M=V, Fe)

Journal Article · Fri Feb 15 00:00:00 EST 2013 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2012.10.007· OSTI ID:22150031

Hamchaoui, Farida ^[1]; Alonzo, Veronique ^[2]; Venegas-Yazigi, Diego ^[3]; Rebbah, Houria ^[1]

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1. Laboratoire des Sciences des Materiaux, Faculte de Chimie, Universite des Sciences et de la Technologie Houari Boumediene, BP 32 El-Alia, 16111 Bab-Ezzouar, Alger (Algeria)
2. Sciences Chimiques de Rennes, UMR6226, Ecole Nationale Superieure de Chimie de Rennes, CNRS, Avenue du General Leclerc, CS 50837, 35708 Rennes Cedex 7 (France)
3. Facultad de Quimia y Biologia, Universitad de Santiago de Chile, USACH, Casilla, 40 Correo 33, Santiago (Chile)

Six new transition metal(III) phosphites A{sup I}[V{sup III}(HPO{sub 3}){sub 2}], where A=K (1), NH{sub 4} (2) and Rb (3) and A{sup I}[Fe{sup III}(HPO{sub 3}){sub 2}] where A=K (4), NH{sub 4} (5) and Rb (6) have been synthesized under hydrothermal conditions and the solid-state structures were solved from single-crystal X-ray diffraction data. These compounds crystallize in the hexagonal system, space group P6{sub 3}mc (no. 186), with a=5.3294(2) A and c=12.3130(5) A for 1, a=5.3330(2) A and c=12.8760(4) A for 2, a=5.3459(2) A and c=12.6850(8) A for 3, a=5.3256(1) A and c=12.2362(3) A for 4, a=5.3229(2) A and c=12.8562(4) A for 5, a=5.3393(2) A and c=12.6913(5) A for 6, with Z=2 in the six phases. The crystal structures of these compounds are isotypic and exhibit a layered structure stacked along the c-axis with the A{sup +} cations located in the interlayer space. The [M{sup III}(HPO{sub 3}){sub 2}]{sup -} sheets are formed by MO{sub 6} octahedra interconnected by HPO{sub 3} tetrahedral phosphite oxoanions through sharing vertices. Thermal analysis shows a large range of stability for compounds containing potassium and rubidium cations with decomposition starting around 550 K for stable compounds and above 840 K for the most stable compounds leading in general to pyrophosphate compounds. Triangular nets of metallic centers are observed within the layers in which antiferromagnetic interactions are evidenced by magnetic susceptibility measurements suggesting magnetic frustration. - Graphical abstract: Six new transition metal(III) phosphites A{sup I}[M{sup III}(HPO{sub 3}){sub 2}], where A=K, NH{sub 4}, Rb and M=V, Fe, have been synthesized. The crystal structures of these compounds are isotypic and exhibit a lamellar structure related to Yavapaiite. The M(HPO{sub 3}){sub 2} layers separated by cationic species present the metallic centers in a triangular arrangement. Bulk antiferromagnetic behavior is observed for all the studied compounds. Highlights: Black-Right-Pointing-Pointer A new family of transition metal phosphites has been prepared. Black-Right-Pointing-Pointer The structure of these compounds is related to layered minerals like Yavapaiite. Black-Right-Pointing-Pointer Antiferromagnetic coupling is evidenced suggesting possible magnetic frustration. Black-Right-Pointing-Pointer Thermal studies show, in general, oxidation of phosphites into pyrophosphates.

• OSTI ID: 22150031
• Journal Information: Journal of Solid State Chemistry, Vol. 198; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANTIFERROMAGNETISM
CATIONS
DECOMPOSITION
HEXAGONAL LATTICES
HYDROTHERMAL SYNTHESIS
INTERACTIONS
LAYERS
MAGNETIC SUSCEPTIBILITY
MONOCRYSTALS
OXIDATION
PHOSPHATES
PHOSPHOROUS ACID
POTASSIUM
PYROPHOSPHATES
SOLIDS
SPACE GROUPS
THERMAL ANALYSIS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS
X-RAY DIFFRACTION