Hybrid spin-crossover conductor exhibiting unusual variable-temperature electrical conductivity.

Area of Science:

• Coordination Chemistry
• Materials Science
• Polymer Chemistry

Background:

• Spin-crossover (SCO) complexes offer potential for advanced electronic and magnetic devices.
• Metallopolymers combine the processability of polymers with the unique properties of metal complexes.
• Developing new ligands is crucial for tuning SCO behavior and creating functional materials.

Purpose of the Study:

• To synthesize a novel terthienyl-substituted QsalH ligand.
• To prepare and characterize an iron(3+) spin-crossover complex incorporating this ligand.
• To investigate the electropolymerization of the complex and the properties of the resulting metallopolymer film.

Main Methods:

• Multistep organic synthesis for ligand preparation.
• Complexation of the ligand with iron(3+).
• Electropolymerization to form a metallopolymer film.
• Variable-temperature magnetic susceptibility measurements.
• Electrical resistivity measurements.

Main Results:

• Successful synthesis of the terthienyl-substituted QsalH ligand and its iron(3+) complex.
• Electropolymerization yielded a hybrid-conducting metallopolymer film (poly1).
• Magnetic susceptibility confirmed spin-crossover behavior in the polymer film.
• Resistivity measurements revealed intriguing temperature-dependent electrical profiles.

Conclusions:

• The new terthienyl-substituted QsalH ligand enables the formation of an iron-based spin-crossover metallopolymer.
• The resulting metallopolymer film exhibits both SCO properties and electrical conductivity.
• The temperature-dependent resistivity suggests potential applications in switchable electronic devices.