Many-body effects at the origin of structural transitions in B₂O₃

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Glassy diboron trioxide (g-B2O3) exhibits complex structural properties under varying pressure conditions.
• Accurate modeling of g-B2O3 requires accounting for many-body effects, which are often challenging to capture.

Purpose of the Study:

• To develop and validate advanced atomic force-field models for glassy diboron trioxide.
• To investigate the structural transitions of g-B2O3 from ambient to high pressure.

Main Methods:

• Utilized two types of atomic force-field models incorporating many-body effects.
• Parameterized models using dipole- and force-fitting procedures with first-principles calculation datasets.
• Validated model predictions against experimental data for structural transitions.

Main Results:

• Developed models that outperform previous ones in predicting g-B2O3 structural properties.
• Identified key physical ingredients: oxide ion polarizability and adaptive size/shape.
• Observed significant changes in short- and medium-range order during structural transitions.

Conclusions:

• The enhanced force-field models provide accurate predictions for g-B2O3 under pressure.
• Many-body effects, particularly polarizability and ion deformability, are crucial for accurate modeling.
• The study advances the understanding of structural behavior in amorphous boron oxides.