Possible high-pressure structures of sulfur trioxide

Area of Science:

• Materials Science
• Solid-State Chemistry
• Computational Physics

Background:

• Sulfur trioxide (SO3) exists in various solid forms.
• Understanding high-pressure phases is crucial for materials science.

Purpose of the Study:

• To computationally investigate the possibility of high-density sulfur trioxide phases.
• To predict accessible high-pressure forms of SO3.

Main Methods:

• Utilized the linearized augmented plane wave (LAPW) method for electronic structure calculations.
• Performed density functional theory (DFT) based simulations.

Main Results:

• Identified several potential high-density forms of sulfur trioxide.
• These forms are predicted to be stable at pressures exceeding 29 GPa.
• Densities up to 1.7 times greater than known SO3 forms are indicated.

Conclusions:

• High-pressure synthesis of novel, denser sulfur trioxide polymorphs is theoretically feasible.
• These findings expand the known phase diagram of sulfur trioxide.