Low- Temperature Transformations in Amorphous Silica Bilayers on Ru(0001) After Crystal-Glass Transition: Closer Look

Area of Science:

• Materials Science
• Surface Science
• Solid-State Chemistry

Background:

• The crystal-glass transition in silicon dioxide (silica) is a critical phenomenon.
• Previous studies identified high-energy Stone-Wales ring-opening as the initial trigger.
• The existence and initiation mechanism of lower-energy transitions at moderate temperatures remained unclear.

Purpose of the Study:

• To investigate low-energy structural transformations in silica films at room temperature.
• To clarify whether measurement techniques can induce structural modifications.
• To understand the role of metal substrates in these transformations.

Main Methods:

• Utilized fast-scanning scanning tunneling microscopy (STM) for real-space observation.
• Employed density functional theory (DFT) calculations to support experimental findings.
• Prepared bilayer silica films on metal substrates for study.

Main Results:

• Observed structural transformations in silica films at room temperature via STM.
• Identified ring structure modifying processes responsible for the transition.
• DFT calculations confirmed experimental observations and elucidated transformation energetics.
• Revealed the significant influence of the metal support on transformation energetics.

Conclusions:

• Structural transformations in silica films can occur at room temperature, initiated by low-energy processes.
• Fast-scanning STM is a viable technique for studying such dynamic transitions in real space.
• Metal substrates play a crucial role in modulating the energetics of silica structural transformations.