摘要
In this study, we prepared sub-micron crystals of one-dimensional (1D) spin-Peierls-type compounds, 1-(4′-R-benzyl)pyridinium-d5 bis(maleonitriledithiolato)nickelate (R = Br or Cl), using a facile method, namely, an acetonitrile solution of each compound was quickly mixed with excess water (an insoluble solvent). This facile method of preparation gave a uniform dispersion of sub-micron crystals with a typical dimension of <1.0 μm. We observed that the reduction in grain size affected the magnetic and phase transition features. With respect to the bulk crystal samples, the powder X-ray diffraction peaks are broadened, the transition temperature (TC) is up-shifted with ΔTC ≈ 1.2 K for R = Br vs. 1.0 K for R = Cl, and the changes of enthalpy and entropy of the phase transition are significantly decreased for the sub-micron crystal samples; in addition, reducing the crystal grain size leads to the onset of a strongly Curie-Weiss-type paramagnetic background and significant temperature-independent paramagnetism.
源语言 | 英语 |
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页(从-至) | 5395-5401 |
页数 | 7 |
期刊 | New Journal of Chemistry |
卷 | 39 |
期 | 7 |
DOI | |
出版状态 | 已出版 - 1 7月 2015 |