Exploiting Structural Flexibility for Reversible Kondo-State Switching in a Pure Organic Radical on...

Area of Science:

• Materials Science
• Quantum Computing
• Surface Science

Background:

• Pure organic radicals are key for spintronic and quantum computing.
• Controlling spin states on surfaces is a major challenge.

Purpose of the Study:

• To investigate adsorption conformations and spin states of Blatter-type triradicals (BTR) on Au(111).
• To demonstrate reversible control over these spin states through structural manipulation and chemical modification.

Main Methods:

• Submolecular characterization using scanning tunneling microscopy/spectroscopy (STM/STS).
• Noncontact atomic force microscopy (nc-AFM).
• Density functional theory (DFT) calculations.

Main Results:

• Identified two distinct adsorption conformations (3A and 3B) of BTR on Au(111).
• Resolved geometry-dependent Kondo states associated with each conformation.
• Achieved reversible in situ switching between Kondo states via tip manipulation.
• Demonstrated reversible spin-state toggling between radical and hydrogenated states through hydrogenation/dehydrogenation.

Conclusions:

• Established a direct relationship between adsorption geometry and spin states in flexible organic radicals.
• Structural flexibility is a viable design principle for molecular spintronic devices.