A Magnetically Robust Triplet Ground State Sulfur-Hydrocarbon Diradical Dication.

Area of Science:

• Organic Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Tetrathiolated pyrene derivatives are of interest for their unique electronic properties.
• Controlling spin states in organic molecules is crucial for developing advanced materials.
• Sulfur-containing organic radicals are challenging to synthesize and characterize.

Purpose of the Study:

• To investigate the one- and two-electron oxidation of a tetrathiolated di-tert-butylpyrene compound.
• To synthesize and characterize the resulting radical cation and diradical dication salts.
• To explore the electronic and magnetic properties, particularly the spin state, of these novel compounds.

Main Methods:

• Synthesis of radical cation salt 1•+[Al(ORF)4]− and diradical dication salt 12+••·2[Al(ORF)4]−.
• Isolation and crystallization of the salts.
• Characterization using single-crystal X-ray diffraction, EPR spectroscopy, SQUID measurements, and UV-vis spectroscopy.

Main Results:

• Stable crystalline radical cation and diradical dication salts were successfully isolated.
• Electron spin density delocalization was observed differently in the radical cation and diradical dication.
• The diradical dication 12+•• exhibits a robust triplet ground state, the first reported for a high-spin sulfur-hydrocarbon diradical.

Conclusions:

• The study demonstrates the successful synthesis and characterization of novel sulfur-hydrocarbon radical salts.
• The diradical dication represents a new class of high-spin organic molecules with potential applications.
• This work provides fundamental insights into the electronic structure and magnetic properties of multicharged sulfur-containing polycyclic aromatic hydrocarbons.