- Tytuł:
- Intramolecular and Lattice Dynamics in V$\text{}_{6-n}^{IV}$V$\text{}_{n}\text{}^{V}$ O$\text{}_{7}$(OCH$\text{}_{3}$)$\text{}_{12}$ Crystal
- Autorzy:
-
Yablokov, Yu. V.
Augustyniak-Jabłokow, M. A.
Borshch, S.
Daniel, C.
Hartl, H. - Powiązania:
- https://bibliotekanauki.pl/articles/2043556.pdf
- Data publikacji:
- 2005-08
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
76.30.Fc
36.40.Cg - Opis:
- Multi-nuclear mixed-valence clusters V$\text{}_{4}^{IV}$V$\text{}_{2}^{V}$O$\text{}_{7}$(OCH$\text{}_{3}$)$\text{}_{12}$ were studied by X-band EPR in the temperature range 4.2-300 K. An isotropic exchange interactions between four V$\text{}^{IV}$ ions with individual spin S$\text{}_{i}$=1/2 determine the energy levels structure of the compound with the total spin states S=0, 1, and 2, which are doubled and split due to the extra electron transfer. The spin-Hamiltonian approach was used for the analysis of the temperature dependences of the EPR spectra parameters and the cluster dynamics. Two types of the electron transfer are assumed: the single jump transfer leading to the splitting of the total spin states by intervals comparable in magnitude with the exchange parameter J≈100-150 cm$\text{}^{-1}$ and the double jump one resulting in dynamics. The dependence of the transition ratesν$\text{}_{tr}$ on the energy of the total spin states was observed. In particular, in the range 300-220 K theν$\text{}_{tr}$ ≈0.7×10$\text{}^{10}$ cm$\text{}^{-1}$ and below 180 K the ν$\text{}_{tr}$≈1×10$\text{}^{10}$ cm$\text{}^{-1}$ was estimated. The g-factors of the spin states were shown to depend on the values of the intermediate spins. A phase transition in the T-range 210-180 K leading to the change in the initial V$\text{}^{IV}$ ions localization was discovered.
- Źródło:
-
Acta Physica Polonica A; 2005, 108, 2; 271-281
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
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