Flux growth of hexagonal bipyramidal ruby crystals

Area of Science:

• Materials Science
• Crystallography
• Solid State Chemistry

Background:

• Ruby (Al2O3:Cr) is a valuable gemstone and laser material.
• Crystal growth methods are crucial for obtaining high-quality ruby crystals.
• Flux growth offers a viable route for synthesizing oxide crystals.

Purpose of the Study:

• To investigate the feasibility of growing hexagonal bipyramidal ruby crystals.
• To evaluate molybdenum trioxide (MoO3) as a flux for ruby crystal growth.
• To characterize the morphology and properties of the synthesized ruby crystals.

Main Methods:

• Crystal growth via isothermal evaporation of MoO3 flux.
• Heating a mixture of aluminum oxide (Al2O3), chromium oxide (Cr2O3), and MoO3 flux at 1100°C for 5 hours.
• Characterization of crystal morphology and dimensions.

Main Results:

• Successfully grew hexagonal bipyramidal ruby crystals.
• Crystals exhibited transparent-red coloration.
• Obtained crystals with lengths up to 1.8 mm and widths up to 1.7 mm.
• Identified well-developed {113} faces on the bipyramidal crystals.
• Molybdenum trioxide proved to be a suitable flux for this growth.

Conclusions:

• Isothermal evaporation of MoO3 flux is an effective method for growing hexagonal bipyramidal ruby crystals.
• The {113} faces are characteristic of ruby crystals grown under these conditions.
• MoO3 is a promising flux for the synthesis of high-quality ruby crystals.