Chemists synthesize an air-stable organic tetraradical with fused 7-5-7 rings
Researchers synthesized a nonalternant hydrocarbon tetraradical in the lab, achieving a 33-day ambient half-life alongside strong spin coupling.
Chemists reported the synthesis and characterization of an air-stable polycyclic hydrocarbon tetraradical in the journal Science Advances science.org
Science Advancesscience.orgOpen source ↗. The open-shell molecule incorporates a nonalternant framework of two fused 7-5-7 ring motifs and exhibits a strongly correlated singlet ground state. Under ambient conditions, the synthesized compound demonstrated a half-life of 33 days.
Measurements confirmed high radical character, with indices calculated at y0 = 1.00 and y1 = 0.89. Magnetic response analyses revealed competing exchange interactions with coupling constants of J1 = +321 K, J2 = −44 K, and J3 = −29 K, indicating coexistence of ferromagnetic and antiferromagnetic pathways.
According to the authors, the nonalternant architecture effectively suppresses hyperfine and vibrational decoherence. This design achieved long spin relaxation and coherence times, providing a strategy to balance chemical stability and spin interactions in open-shell organic frameworks for quantum information science.
