A single-component molecular metal based on a thiazole dithiolate gold complex

Area of Science:

• Materials Science
• Solid-State Physics
• Supramolecular Chemistry

Background:

• Single-component molecular conductors are crucial for advanced electronic devices.
• Developing new materials with tunable conductivity is an ongoing challenge.

Purpose of the Study:

• To isolate and characterize a novel single-component molecular conductor.
• To investigate the pressure-dependent conductivity and electronic properties of the material.

Main Methods:

• Electrocrystallization of a gold bis(dithiolene) complex with N-ethyl-1,3-thiazoline-2-thione-4,5-dithiolate (Et-thiazdt) ligand.
• X-ray crystallography to determine the crystal structure.
• Variable-temperature and variable-pressure conductivity measurements.
• First-principles Density Functional Theory (DFT) calculations.

Main Results:

• Isolation of a single-component molecular conductor with a layered structure of 1D molecular stacks.
• The material is semiconducting at ambient conditions (0.33 S cm⁻¹) and becomes metallic under pressure, reaching 1000 S cm⁻¹ at 21 kbar.
• A semiconductor-to-metal crossover is observed at 13 kbar.
• DFT calculations reveal an antiferromagnetic ground state with a small band gap, and simulations explain the pressure-induced conductivity changes.

Conclusions:

• This work presents the first well-characterized single-component molecular metal not relying on TTF dithiolate ligands.
• The material's conductivity is highly sensitive to pressure, demonstrating a clear pathway to stabilize the metallic state.
• The findings provide fundamental insights into the design and control of molecular conductors.