The pyrochlore-type molybdate Pr2Mo1.73Sc0.27O7

Area of Science:

• Solid-state chemistry
• Crystallography
• Materials science

Background:

• The pyrochlore structure (A2B2O7) is a versatile framework for various functional materials.
• Understanding the atomic arrangement and site occupancy in substituted pyrochlores is crucial for predicting properties.

Purpose of the Study:

• To elucidate the crystal structure of dipraseodymium molybdenum scandium hepta-oxide, Pr2Mo1.73Sc0.27O7.
• To determine the precise atomic positions and site occupancies of molybdenum and scandium within the pyrochlore lattice.

Main Methods:

• Single-crystal X-ray diffraction was employed to analyze the crystal structure.
• Rietveld refinement was used to determine atomic positions and site occupancies.

Main Results:

• The compound crystallizes in the cubic pyrochlore-type structure.
• Molybdenum (Mo) and scandium (Sc) atoms are statistically distributed over the same crystallographic site (16d) with specific site-occupancy factors.
• Praseodymium (Pr) ions are coordinated by eight oxygen atoms, forming a ditrigonal scalenohedron.

Conclusions:

• The detailed crystal structure of Pr2Mo1.73Sc0.27O7 has been determined.
• The statistical distribution of Mo and Sc influences the overall framework and local coordination environments.
• This structural information is fundamental for exploring potential applications of this material.