Structure solution with automated electron diffraction tomography data: different instrumental approaches

Area of Science:

• Materials Science
• Crystallography
• Electron Microscopy

Background:

• Automated electron diffraction tomography (AEDT) has become a standard technique for solving the structures of nano-crystalline materials.
• AEDT utilizes arbitrary tilt axes and non-oriented diffraction patterns for high-quality intensity data.
• Electron beam precession further enhances data quality by sampling intensities between reciprocal space slices.

Purpose of the Study:

• To demonstrate that manual data collection can yield electron diffraction data comparable in quality to automated methods.
• To validate the suitability of manually collected data for ab initio structure solution and refinement.
• To test the technique on a challenging low-symmetry material, triclinic sodium tetratungstate (Na(2)W(4)O(13)).

Main Methods:

• Collected electron diffraction tomography data using both automated and manual techniques.
• Investigated the impact of electron beam precession on data quality.
• Employed a manual method mimicking the automated process for data acquisition.

Main Results:

• Electron diffraction data of comparable quality were obtained using both automated and manual collection methods.
• Data collected with and without electron beam precession proved suitable for ab initio structure solution.
• The manual technique successfully provided data for the complex triclinic sodium tetratungstate structure.

Conclusions:

• Manual electron diffraction tomography is a viable alternative to automated methods for structure solution.
• The manual approach, even without precession, can generate sufficient data quality for ab initio refinement.
• This finding expands the accessibility of advanced crystallographic structure determination techniques.