23 Na-NMR study on the one-dimensional superoxide spin-chain compound NaO 2
Researchers used Na-NMR to study NaO2, a one-dimensional quantum spin system. They found that NaO2 has a spin gap of 38 K, suggesting it behaves like a spin-Peierls material. Structural changes in the compound confirm its one-dimensional nature through specific atomic alignments and sharp drops in coupling constants.