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Synthèse et étude structurale de Na9Cr(MoO4)6.
Wassim Dridi1, Ines Ennajeh1, Mohamed Faouzi Zid1
1Laboratoire de Matériaux et Cristallochimie, Faculté des Sciences de Tunis, Université de Tunis El Manar, 2092 El Manar Tunis, Tunisia.
Summary
Nona-sodium chromium(III) hexa-kis[molybdate(VI)], Na9Cr(MoO4)6, was synthesized. Its structure features polyhedral clusters with a chromium(III) oxide core and sodium cations within an open framework, confirmed by bond-valence-sum analysis.
Area of Science:
- Inorganic Chemistry
- Solid-State Chemistry
- Materials Science
Background:
- The synthesis and structural characterization of novel inorganic compounds are crucial for developing new materials.
- Molybdates and chromates are classes of compounds with diverse structural motifs and potential applications.
Purpose of the Study:
- To synthesize and characterize the novel compound nona-sodium chromium(III) hexa-kis[molybdate(VI)], Na9Cr(MoO4)6.
- To elucidate the crystal structure and bonding characteristics of the title compound.
Main Methods:
- Solid-state reaction method for synthesis.
- X-ray crystallography for structural determination.
- Bond-valence-sum model for charge validation.
Main Results:
- The compound Na9Cr(MoO4)6 was successfully prepared via solid-state reactions.
- The crystal structure reveals isolated polyhedral clusters with a central CrO6 octahedron linked to six MoO4 tetrahedra, forming an open framework.
- Sodium cations (Na+) occupy positions within this framework, interacting with the molybdate tetrahedra.
Conclusions:
- The structure of Na9Cr(MoO4)6 is confirmed, showcasing a unique open framework architecture.
- The compound is isotypic with previously reported Na9Sc(MoO4)6 and Na9Fe(MoO4)6, highlighting structural similarities within this family of compounds.
- The bond-valence-sum model supports the assigned ionic charges, validating the structural model.
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