- Tytuł:
- EPR Study of the Phase Transition in Dimethylammonium Gallium Sulfate Hexahydrate
- Autorzy:
-
Hrabański, R.
Janiec-Mateja, M.
Czapla, Z. - Powiązania:
- https://bibliotekanauki.pl/articles/2043560.pdf
- Data publikacji:
- 2005-08
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
64.70.Kb
76.30.Fc
77.80.-e - Opis:
- X-band electron paramagnetic resonance investigations of single crystals of Cr$\text{}^{3+}$-doped dimethylammonium gallium sulphate hexahydrate are presented from room temperature down to 110 K. The crystal undergoes a order-disorder phase transition to ferroelectric phase at 134 K and additionally a first-order transition into a low temperature non-ferroelectric phase at T$\text{}_{c2}$=116 K. The spin-Hamiltonian parameters were determined for paraelectric and ferroelectric phases. The spin-Hamiltonian parameters in the paraelectric phase are: g=1.982±0.002, b$\text{}_{2}^{0}$=(890±10)×10$\text{}^{-4}$ cm$\text{}^{-1}$, b=(386±15)×10$\text{}^{-4}$ cm$\text{}^{-1}$. Remarkable EPR line width changes confirm the order-disorder character of the ferroelectric phase transition. Additionally observed triplet lines demonstrate freezing-out of dimethylammonium reorientations which can be considered as a prime reason for this transition similarly as observed in dimethylammonium aluminium sulfate hexahydrate.
- Źródło:
-
Acta Physica Polonica A; 2005, 108, 2; 283-290
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł