Rb2Lu[Si4O10]F, a tubular chain silicate

Area of Science:

• Inorganic Chemistry
• Crystal Chemistry
• Materials Science

Background:

• Tubular chain silicates represent a unique class of inorganic compounds characterized by condensed tetrahedral silicate units forming closed columns.
• Understanding the synthesis and structural intricacies of novel silicate frameworks is crucial for advancing materials science and solid-state chemistry.

Purpose of the Study:

• To synthesize and characterize single crystals of a new compound, dirubidium lutetium tetra-silicate fluoride (Rb2Lu[Si4O10]F).
• To elucidate the crystal structure and bonding environment within this novel tubular chain silicate.

Main Methods:

• Flux-synthesis experiments utilizing SiO2, Lu2O3, and RbF as starting materials.
• Single-crystal X-ray diffraction analysis to determine the atomic arrangement and structural parameters.

Main Results:

• Successful synthesis of single crystals of Rb2Lu[Si4O10]F.
• The compound crystallizes as a tubular chain silicate with a periodicity of four along the b axis.
• Lutetium cations are octahedrally coordinated by four oxide and two fluoride anions, forming chains linked by shared fluoride corners parallel to the silicate tubes.

Conclusions:

• Rb2Lu[Si4O10]F represents a new member of the tubular chain silicate family.
• The crystal structure is stabilized by the coordination of lutetium and the arrangement of silicate tetrahedra, with rubidium cations ensuring overall charge neutrality.