Single-component molecular conductor [Pt(dmdt)₂]-a three-dimensional ambient-pressure molecular Dirac electron system

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid-State Chemistry

Background:

• Single-component molecular conductors are of great interest for electronic applications.
• The molecular conductor [Pt(dmdt)2] is a prime candidate for studying Dirac electron systems under ambient conditions.
• Understanding its electronic properties is crucial for developing novel electronic materials.

Purpose of the Study:

• To investigate the electronic structure of the single-component molecular conductor [Pt(dmdt)2].
• To confirm the presence and nature of Dirac electrons in this system.
• To elucidate the origin of its unique conductivity and magnetic properties.

Main Methods:

• First-principles Density Functional Theory (DFT) calculations were employed.
• Analysis of electronic band structure to identify Dirac cones.
• Investigation of conductivity and magnetic susceptibility measurements.

Main Results:

• The material [Pt(dmdt)2] exhibits a high temperature-insensitive conductivity.
• Magnetic susceptibility is temperature-dependent and nearly vanishes below 120 K.
• DFT calculations revealed the emergence of Dirac cones along the a* direction, forming Dirac nodal lines.

Conclusions:

• The single-component molecular conductor [Pt(dmdt)2] is confirmed as an ambient-pressure molecular Dirac electron system.
• The observed electronic and magnetic properties are consistent with the presence of Dirac nodal lines.
• This finding opens avenues for the design of novel molecular electronic devices.