Magnetic studies of VSe2

The magnetic susceptibility of the layered compound V${\mathrm{Se}}_2$ is known to be very sensitive to preparation conditions. Preparation at temperatures above 580°C produces interstitial (intercalated) V atoms that induce a paramagnetic moment and a Curie contribution to the susceptibility. We show that as the density of these defects increases, the charge-density-wave (CDW) onset temperature is decreased from 111±1 K at a rate of 13±3 K/at.% V interstitials, and the magnitude of the CDW anomaly in the susceptibility is also decreased. No evidence for further transitions below 111 K is obtained, although a small (0.2%) hysteresis is observed between 115 and 145 K. However, at present the source of this hysteresis is not understood.