| Attributs | Valeurs |
|---|
| type
| |
| Is Part Of
| |
| Subject
| |
| Title
| - Low-lying magnetic excitations and magnetocaloric effect of molecular magnet K 6[V 15As 6O 42(H 2O)] · 8H 2O
|
| Date
| |
| has manifestation of work
| |
| related by
| |
| Author
| |
| Abstract
| - Low-temperature heat capacity measurements were performed on the molecular nanomagnet $\text{K}_{6}[\text{V}_{15}\text{As}_{6}\text{O}_{42}(\text{H}_{2}\text{O})] \cdot8\text{H}_{2}{\text{O}}$ (V15). The low-lying magnetic excitations are clearly evidenced by the Schottky anomalies in the specific-heat data. The energy levels determined from the low-temperature observables agree well with the three-spin model for V15. The magnetocaloric effect of V15 is examined. The maximum entropy change of $5.31\ \text{Jkg}^{-1}\text{K}^{-1}$ is found for a field change of $\Delta H =(8-0.5)\ \text{T}$ at ${\sim}1.5\ \text{K}$ . In spite of the low ground-state spin of V15, a drastic entropy change of $4.12\ \text{Jkg}^{-1}\text{K}^{-1}$ is observed for a field change of $\Delta H = (8-0.05)\ \text{T}$ at 0.4 K, which is comparable to the entropy change of some high-spin sub-kelvin magnetic coolers at such low temperatures. Anisotropy and consequent zero-field splitting result in this characteristic of V15 and may open new possibilities in the design of ultra-low-temperature molecular coolers.
|
| article type
| |
| publisher identifier
| |
| Date Copyrighted
| |
| Rights
| |
| Rights Holder
| |
| is part of this journal
| |
| is primary topic
of | |
