Spin-gap formation due to spin-Peierls instability in $\pi$-orbital-ordered NaO${}_2$

Mizuki Miyajima, Fahmi Astuti, Takahito Fukuda +11

We have investigated the low-temperature magnetism of sodium superoxide (NaO${}_2$), in which spin, orbital, and lattice degrees of freedom are closely entangled. The magnetic susc…