Plastic phase transitions in tris(hydroxymethyl)aminomethane perchlorate

Area of Science:

• Materials Science
• Crystallography
• Solid-State Chemistry

Background:

• Organic crystal materials are crucial for flexible smart devices, requiring metal-free and low molecular mass properties.
• Developing novel materials with switchable functionalities is essential for advancing electronic applications.

Purpose of the Study:

• To report a novel metal-free plastic crystal, tris(hydroxymethyl)aminomethane perchlorate (Tris-HClO4).
• To investigate its crystallographic and phase transition properties.
• To evaluate its potential for multifunctional switchable materials.

Main Methods:

• Crystallization of tris(hydroxymethyl)aminomethane perchlorate (Tris-HClO4).
• X-ray powder diffraction (PXRD) for structural analysis.
• Thermal analysis to determine phase transition temperatures and entropy changes.
• Dielectric measurements to assess switching properties.

Main Results:

• Tris-HClO4 crystallizes in the R3̄ space group at room temperature.
• A plastic phase transition occurs at 369 K with a large entropy gain (70.5 J mol⁻¹ K⁻¹).
• The high-temperature phase exhibits cubic lattice symmetry.
• Excellent dielectric permittivity switching properties and robust cyclic stability were observed.

Conclusions:

• Tris-HClO4 is a promising metal-free plastic crystal for flexible smart devices.
• The combination of plastic phase transition and symmetry breaking offers a pathway for designing novel switchable materials.
• This research contributes to the development of advanced functional organic materials.