Characterization of powellite-based solid solutions by site-selective time resolved laser fluorescence spectroscopy.

Area of Science:

• Solid-state chemistry
• Materials science
• Spectroscopy

Background:

• The Ca2(MoO4)2-NaGd(MoO4)2 system is a solid solution with potential applications.
• Understanding the local structure and ion incorporation is crucial for material properties.

Purpose of the Study:

• To investigate the homogeneity and local structure of the Ca2(MoO4)2-NaGd(MoO4)2 solid solution system.
• To determine the coordination environment and ligand-metal interactions of incorporated trivalent ions.

Main Methods:

• Site-selective time-resolved laser fluorescence spectroscopy (TRLFS) using Eu(3+) as a fluorescent probe.
• Analysis of polycrystalline samples across the entire composition range.
• Polarization-dependent measurements on a single crystal of NaGd(Eu)(MoO4)2.

Main Results:

• The solid solution system is confirmed to be homogeneous across the entire composition range.
• Trivalent ions (Eu3+) substitute homogeneously for Gd3+ in the powellite structure.
• A single coordination environment with strong ligand-metal interaction was identified for trivalent ions.
• The coordination geometry was determined to be of C2v point symmetry.

Conclusions:

• The study provides molecular-level insights into the Ca2(MoO4)2-NaGd(MoO4)2 solid solution.
• The findings confirm the structural integrity and coordination preferences within this material system.
• TRLFS is a powerful technique for probing local coordination in solid solutions.