Redetermination of Ce[B(5)O(8)(OH)(H(2)O)]NO(3)·2H(2)O

Area of Science:

• Inorganic Chemistry
• Crystallography
• Materials Science

Background:

• Previous structural determination of cerium(III) aqua-hydroxidoocta-oxidopenta-borate nitrate dihydrate had limitations.
• Accurate structural information is crucial for understanding the properties and potential applications of borate compounds.

Purpose of the Study:

• To redetermine the crystal structure of Ce[B(5)O(8)(OH)(H(2)O)]NO(3)·2H(2)O with higher precision.
• To clarify the arrangement of polyborate anions, coordination of cerium ions, and hydrogen bonding network.

Main Methods:

• Single-crystal X-ray diffraction.
• Refinement of crystal structure including hydrogen atom locations.
• Bond-valence-sum calculations.

Main Results:

• The crystal structure was resolved with all hydrogen atoms located, revealing distinct fundamental building blocks (FBBs) of polyborate anions.
• Corrugated polyborate layers, built from [B(5)O(8)(OH)(H(2)O)](2-) anions, stack along [010] and are linked by Ce(3+) ions with a distorted CeO(10) coordination.
• Hydrogen bonds between water molecules and nitrate anions stabilize the inter-layer space, and the [BO(3)(H(2)O)]-group exhibits a distorted [3+1] coordination.

Conclusions:

• The redetermined structure provides a more accurate description of cerium(III) aqua-hydroxidoocta-oxidopenta-borate nitrate dihydrate.
• Understanding the detailed crystal structure, including polyborate anion arrangement and hydrogen bonding, is key for future research on cerium borates.