Magnetic susceptibility of carbon structures

Abstract

Measurements of the magnetic moment and susceptibility of diamond, graphite along and perpendicular to the c axis, ${\mathrm{C}}_{60}$, and carbon nanotubes are reported as a function of magnetic field (0H55 kOe) and temperature (4.5 KT310 K). The data on ${\mathrm{C}}_{60}$ are diamagnetic, confirm previous results, and show the influence of the phase transition near 260 K. The data on the nanotubes were taken on a sample containing a distribution of tubes with diameters in the 2--10 nm range, and reveal a mostly diamagnetic behavior with a magnetic field and temperature dependence different from graphite.