Electron spin resonance of doped chalcogenide nanotubes

$X$-band ESR of lithium doped ${\mathrm{MoS}}_2$ nanotubes is reported for temperatures between room temperature and 4 K. Two distinct ESR components were observed: a narrow component with a linewidth of about 4 G and a broad component with a linewidth of more than 800 G. The broad ESR component is attributed to Mo d-orbital-derived conducting band of ${\mathrm{MoS}}_2$ nanotubes. The large weakly temperature-dependent ESR spin susceptibility of charged ${\mathrm{MoS}}_2$ nanotubes is thought to reflect strong electronic correlations and one-dimensional electronic structure with the presence of van Hove singularities in the density of states. The broad ESR component is discussed in terms of conducting electrons coupled to defects and in terms of random-exchange Mo Heisenberg chain model. The narrow component is suggested to be due to the formation of small spin clusters.