Low Temperature Magnetic Properties of Organic Radical Magnet, MOTMP

Abstract
The magnetic properties of MOTMP 4-methacryloyloxy-2,2,6,6-tetramethyl-piperidin-1-oxyl are studied at tempratures below 1 K. The dominant magnetic coupling between the radicals is ferromagnetic. The one-dimensional behavior observed in the temperature dependence of susceptibility is consistent with previous result of heat capacity measurement in which the intrachain ferromagnetic interaction is estimated to be J / k =0.9 K. The susceptibility in the ordered state, however, shows spin-flip transition, which reveals antiferromagnetic long range order. From the analysis of ordering temperature T N and critical field H C , the interchain interactions are also estimated by the mean field theory.