Improved dopant fraction variance estimation in statistical ALCHEMI based on correct error propagation rule.

Area of Science:

• Materials Science
• Solid-State Chemistry
• Analytical Chemistry

Background:

• Statistical atom location by channeling enhanced microanalysis (SALCEMA) is a key technique for determining dopant site occupancy.
• Accurate quantification of dopant fractions and their uncertainties is crucial for understanding material properties.
• Existing methods may contain errors, particularly at low dopant concentrations or when dopants occupy multiple inequivalent sites.

Purpose of the Study:

• To revise the error propagation rule in SALCEMA for accurate dopant site occupancy determination.
• To propose a new equation for calculating uncertainty in dopant fractions.
• To address limitations in current methods concerning low dopant concentrations and variable site occupancies.

Main Methods:

• Revisiting the statistical atom location by channeling enhanced microanalysis (SALCEMA) method.
• Applying an appropriate error propagation rule to correct dopant site occupancy errors.
• Developing and validating a revised equation for dopant fraction uncertainty calculation.

Main Results:

• A corrected error propagation rule for SALCEMA has been established.
• A novel equation for calculating the uncertainty in determined dopant fractions is proposed.
• The revised method demonstrates improved accuracy for low dopant concentrations and complex site occupancies.

Conclusions:

• The proposed revised equation enhances the accuracy of dopant fraction uncertainty quantification in SALCEMA.
• This advancement is particularly significant for materials with low dopant levels or heterogeneous dopant distribution.
• The validated approach using Eu-doped Ca2SnO4 provides a reliable method for precise dopant site analysis.