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Low-Temperature Properties of Quasi-One-Dimensional Molecule-Based Ferromagnets

Takashi Nakanishi·Shoji Yamamoto·Toru Sakai
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Abstract

Quantum and thermal behaviors of low-dimensional mixed-spin systems are investigated with particular emphasis on the design of molecule-based ferromagnets. One can obtain a molecular ferromagnet by assembling molecular bricks so as to construct a low-dimensional system with a magnetic ground state and then coupling the chains or the layers again in a ferromagnetic fashion. Two of thus-constructed quasi-one-dimensional bimetallic compounds are qualitatively viewed within the spin-wave treatment, one of which successfully grows into a bulk magnet, while the other of which ends in a singlet ground state. Then, concentrating on the ferrimagnetic arrangement on a two-leg ladder which is well indicative of general coupled-chain ferrimagnets, we develop the spin-wave theory and fully reveal its low-energy structure. We inquire further into the ferromagnetic aspect of the ferrimagnetic ladder numerically calculating the sublattice magnetization and the magnetic susceptibility. There exists a moderate coupling strength between the chains in order to obtain the most ferromagnetic ferrimagnet.

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Takashi Nakanishi, Shoji Yamamoto, Toru Sakai. 2001-02-23. Low-Temperature Properties of Quasi-One-Dimensional Molecule-Based Ferromagnets. https://doi.org/10.1143/jpsj.70.1380

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