The thermal and magnetic properties of neodymium ethylsulphate at low temperatures

Abstract The entropy, the specific heat and the absolute temperature have been determined as a function of the magnetic temperature for a single crystal of neodymium ethylsulphate in the temperature range between 0·016 and 1°K by adiabatic demagnetization experiments. The specific heat values were confirmed by determination of the magnetic specific heat between 1°K and 2°K by the paramagnetic relaxation method. The results are compared with those expected from paramagnetic resonance data and from Daniels' extension of Van Vleck's theory of dipolar interaction effects. Good agreement is found down to temperatures of about 0·05°K.

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