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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Nonmagnetic ground states and phase transitions in the caged compounds PrT2Zn20 (T = Ru, Rh and Ir)
T Onimaru1, K T Matsumoto, N Nagasawa
1AdSM, Hiroshima University, Higashi-Hiroshima 739-8530, Japan. onimaru@hiroshima-u.ac.jp
Abstract:
We performed electrical resistivity ρ, magnetic susceptibility χ, specific heat C and electron diffraction measurements on single-crystalline samples of PrT2Zn20 (T = Ru, Rh and Ir). The three compounds show the Van Vleck paramagnetic behavior, indicating the nonmagnetic crystalline electric field (CEF) ground states. A Schottky-type peak appears at around 14 K, irrespective of the T element, which can be moderately reproduced by a doublet–triplet model. For T = Ru, a structural transition occurs at Ts = 138 K, below which no phase transition appears down to 0.04 K. On the other hand, for T = Ir, antiferroquadrupole (AFQ) ordering arising from the nonmagnetic Γ3 doublet takes place at TQ = 0.11 K. For T = Rh, despite a structural transition between 170 and 470 K, the CEF ground state is still the non-Kramers Γ3 doublet. However, no phase transition due to the Γ3 doublet was observed even down to 0.1 K.
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