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arXiv · cond-mat/9807348

Magnetic Properties of a Quantum Ferrimagnet: NiCu(pba)(D_2O)_3 . 2D_2O

Masayuki Hagiwara·Kazuhiko Minami·Yasuo Narumi·Keiji Tatani·Koichi Kindo
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Abstract

We report the results of magnetic measurements on a powder sample of NiCu(pba)(D_2O)_3 \cdot 2D_2O$ (pba=1,3-propylenebis(oxamato)) which is one of the prototypical examples of an $S$=1/2 and 1 ferrimagnetic chain. Susceptibility($χ$) shows a monotonous increase with decreasing temperature (T) and reaches a maximum at about 7 K. In the plot of $χT$ versus $T$, the experimental data exhibit a broad minimum and are fit to the $χT$ curve calculated for the ferrimagnetic Heisenberg chain composed of S=1/2 and 1. From this fit, we have evaluated the nearest-neighbor exchange constant $J/k_B=121 K$, the g-values of Ni$^{2+}$ and Cu$^{2+}$, $g_{Ni}$=2.22 and $g_{Cu}$=2.09, respectively. Applied external field dependence of $χT$ at low temperatures is reproduced fairly well by the calculation for the same ferrimagnetic model.

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Masayuki Hagiwara, Kazuhiko Minami, Yasuo Narumi, Keiji Tatani, Koichi Kindo. 1998-07-27. Magnetic Properties of a Quantum Ferrimagnet: NiCu(pba)(D_2O)_3 . 2D_2O. https://doi.org/10.1143/jpsj.67.2209

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