Fully electron-transferred donor/acceptor layered frameworks with TCNQ(2-)

Area of Science:

• Materials Science
• Solid-State Chemistry
• Supramolecular Chemistry

Background:

• Two-dimensional layered frameworks offer unique electronic properties.
• Electron donor (D) and acceptor (A) units are crucial for designing functional materials.
• Understanding charge transfer in D2A frameworks is key to controlling material properties.

Purpose of the Study:

• To synthesize and characterize novel two-electron transferred D(+)2A(2-) systems in D2A frameworks.
• To investigate the relationship between electronic structure and ionic states.
• To establish a method for predicting and controlling charge transfer regimes.

Main Methods:

• Synthesis of D2A frameworks using paddlewheel-type [Ru2(II,II)(R-PhCO2)4] complexes and TCNQRx.
• Analysis of ionic states using HOMO/LUMO energies and redox potentials.
• Development and application of ionization diagrams (ΔEH-L(DA) vs ΔE1/2(DA) and ΔEH-L(DA) vs U) to determine charge transfer regimes.

Main Results:

• Successful synthesis of five D(+)2A(2-) compounds (1-5).
• All synthesized compounds were paramagnetic due to S = 3/2 spins in quasi-isolated [Ru2(II,III)](+) units.
• Established diagrams effectively determined the ionic states (1e-I or 2e-I) and confirmed charge-oriented design possibilities.

Conclusions:

• The study demonstrates the successful synthesis of D(+)2A(2-) systems in D2A frameworks.
• The developed diagrams provide a reliable method for predicting and controlling electron transfer.
• This work facilitates the rational design of advanced layered materials with tailored electronic properties.