Synthesis, structure, and physicochemical investigations of the new {alpha} Cu{sub 0.50}TiO(PO{sub 4}) oxyphosphate

Journal Article · Thu Feb 15 00:00:00 EST 2007 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2006.10.040· OSTI ID:21015709

Benmokhtar, S ^[1]; Belmal, H ^[1]; Chaminade, J P ^[2]; Gravereau, P ^[2]; Pechev, S ^[2]; Grenier, J C ^[2]; Villeneuve, G ^[3]; Waal, D de ^[4]

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1. Laboratoire de Chimie des Materiaux Solides (LCMS), Universite Hassan II Mohammedia, Faculte des Sciences Ben M'Sik, Casablanca (Morocco)
2. Institut de Chimie de la Matiere Condensee de Bordeaux (ICMCB-CNRS), Universite de Bordeaux1, 33608 Pessac (France)
3. CRPAA, UMR 5060, Universite Bordeaux, 33607-CNRS Pessac (France)
4. Department of Chemistry, University of Pretoria, 0002 Pretoria (South Africa)

The room-temperature crystal structure of a new Cu(II) oxyphosphate-{alpha} Cu{sub 0.50} {sup II}TiO(PO{sub 4})-was determined from X-ray single crystals diffraction data, in the monoclinic system, space group P2{sub 1}/c. The refinement from 5561 independent reflections lead to the following parameters: a=7.5612(4)A, b=7.0919(4)A, c=7.4874(4)A, {beta}=122.25(1){sup o}, Z=4, with the final R=0.0198, wR=0.0510. The structure of {alpha} Cu{sub 0.50} {sup II}TiO(PO{sub 4}) can be described as a TiOPO{sub 4} framework constituted by chains of tilted corner-sharing [TiO{sub 6}] octahedra running parallel to the c-axis and cross linked by phosphate [PO{sub 4}] tetrahedra, where one-half of octahedral cavities created are occupied by Cu atoms. Ti atoms are displaced from the center of octahedra units in alternating long (2.308 A) and short (1.722 A) Ti-O(1) bonds along chains. Such O(1) atoms not linked to P atoms justify the oxyphosphate formulation {alpha} Cu{sub 0.50}TiO(PO{sub 4}). The divalent cations Cu{sup 2+} occupy a Jahn-Teller distorted octahedron sharing two faces with two [TiO{sub 6}] octahedra. EPR and optical measurements are in good agreement with structural data. The X-ray diffraction results are supported by Raman and infrared spectroscopy studies that confirmed the existence of the infinite chains -Ti-O-Ti-O-Ti-. {alpha} Cu{sub 0.50}TiO(PO{sub 4}) shows a Curie-Weiss paramagnetic behavior in the temperature range 4-80 K. - Graphical abstract: Projection of the structure of {alpha} Cu{sub 0.50}TiO(PO{sub 4}) along the a-axis.

• OSTI ID: 21015709
• Journal Information: Journal of Solid State Chemistry, Vol. 180, Issue 2; Other Information: DOI: 10.1016/j.jssc.2006.10.040; PII: S0022-4596(06)00570-6; Copyright (c) 2006 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

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ABSORPTION SPECTROSCOPY
COPPER COMPOUNDS
COPPER IONS
ELECTRON SPIN RESONANCE
INFRARED SPECTRA
JAHN-TELLER EFFECT
MONOCLINIC LATTICES
MONOCRYSTALS
PARAMAGNETISM
PHOSPHATES
SPACE GROUPS
SYNTHESIS
TEMPERATURE RANGE 0273-0400 K
TITANIUM COMPOUNDS
X-RAY DIFFRACTION