The Rare-earth Based Single-ion Magnet $CsNd(MoO_{4})_{2}$

Specific heat, magnetization and DC susceptibility of the single crystal $CsNd(MoO_{4})_{2}$,a layered rare-earth dimolybdate, have been investigated nominally, in the temperature range from 100 mK to 300 K in the magnetic field up to 5 T, applied along the a axis. The analysis of the experimental data revealed the absence of a phase transition to the magnetic ordered state down to 100 mK. The application of a standard two-level model yielded an excellent agreement with the specific heat data above 2 K in nonzero magnetic field indicating a weakness of magnetic correlations and a predominant occupation of the ground-energy doublet. The latter indicates a large energy separation between the ground and first excited doublet. These measurements suggest that $CsNd(MoO_{4})_{2}$ can represent a good realization of a single-ion magnet.