- Tytuł:
- Magnetic specific heat of anion-radical salt [Ni(bipy)₃](TCNQ)₄·(CH₃)₂CO at very low temperatures
- Autorzy:
-
Šoltésová, D.
Čižmár, E.
Vasylets, G.
Starodub, V.
Feher, A. - Powiązania:
- https://bibliotekanauki.pl/articles/1053060.pdf
- Data publikacji:
- 2017-04
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
65.40.Ba
75.30.Et
75.30.Gw - Opis:
- Thermodynamic studies of the anion-radical salt system [Ni(bipy)₃](TCNQ)₄·(CH₃)₂CO, where TCNQ is 7,7',8,8'-tetracyano-quinodimethane, are reported. The anion-radical salt systems based on TCNQ belong to a material class in which the arrangement of the anion-radical salt has considerable impact on the charge transfer and magnetic properties. The crystal structure of the studied compound consists of [Ni(bipy)₃]⁺² cations containing Ni⁺² ions and four types of crystallographically independent anion-radicals TCNQ^{·-} (A, B, C and D). These TCNQ^{·-} radicals form two different types of TCNQ^{·-} stacks (AABB and CCDD), where a strong exchange interaction is expected. The temperature dependence of the specific heat of a single crystal was studied in magnetic fields up to 5 T and in the temperature range from 0.4 K to 30 K. The temperature dependence of specific heat displays a broad Schottky-like maximum above 0.4 K. Using a single-ion approximation, the analysis of the temperature dependence of the specific heat below 10 K yields values for the anisotropy parameters, D/k_{B}=-1.95 K and E/k_{B}=0.3 K. These results suggest that the observed maximum in the specific heat originates from Ni⁺² ions while the exchange interaction between the transition metal ions and the TCNQ is negligible.
- Źródło:
-
Acta Physica Polonica A; 2017, 131, 4; 925-927
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki