Mosaic spread characterization of microgravity-grown tetragonal lysozyme single crystals

Area of Science:

• Crystallography
• Materials Science
• Space Science

Background:

• Understanding crystal growth in microgravity is crucial for materials science.
• Mosaic spread, a measure of crystal lattice imperfections, affects diffraction quality.
• Previous studies on Earth-based crystal growth provide comparative data.

Purpose of the Study:

• To measure mosaic spread values of crystals grown in microgravity.
• To compare these values with those of Earth-grown crystals.
• To analyze the domain structure and its influence on diffraction.

Main Methods:

• Synchrotron radiation was used to measure diffraction line profiles.
• Full Width at Half Maximum (FWHM) values were determined.
• Crystals were analyzed for domain composition and distribution.

Main Results:

• Mosaic spread values (FWHM) ranged from 10-20 arc seconds.
• These values are similar to those from Earth-grown crystals (gel-acupuncture method).
• Crystals contained 2-5 domains, with peak widths of 5-15 arc seconds.
• Domain distribution was found to be non-homogeneous and anisotropic.

Conclusions:

• Microgravity crystal growth yields mosaic spread comparable to terrestrial methods.
• Non-homogeneous and anisotropic domain distribution affects crystal quality and diffraction.
• Mosaic spread significantly influences data collection for high-resolution diffraction studies.