Fujita Wataru
General Education, Faculty of Science and Technology, Seikei University 3-3-1 Kichijoji-kitamachi, Musashino-shi Tokyo 180-8633 Japan
RSC Adv. 2018 Sep 19;8(57):32490-32496. doi: 10.1039/c8ra07134a. eCollection 2018 Sep 18.
Basic copper formate, [Cu(OH)(HCOO)], was selectively prepared by hydrolysis of formate ions in concentrated aqueous solutions of copper formate. This material exhibits a two-dimensional distorted triangular-lattice magnetic network of Cu(ii) ions where = 1/2. The dominance of antiferromagnetic interactions with / = 35.7(2) K and a magnetic anomaly at approximately 2.3 K that corresponds to a paramagnetic-to-antiferromagnetic ordering transition were revealed by magnetic measurements. The field dependence of the magnetisation at 2 K corresponds to the 1/3-magnetisation plateau that is commonly observed in a two-dimensional triangular-lattice system. Moreover, heat-capacity measurements found a λ-type anomaly at 2.15 K, which is the magnetic transition temperature. This material may be a good candidate for a geometrical frustration system with novel magnetic phenomena such as spin-liquid states.
碱式甲酸铜[Cu(OH)(HCOO)]是通过在甲酸铜浓水溶液中水解甲酸根离子选择性制备的。这种材料呈现出二维扭曲的三角形晶格铜（II）离子磁性网络，其中自旋量子数S = 1/2。通过磁性测量揭示了反铁磁相互作用占主导，其J/k = 35.7(2) K，并且在约2.3 K处存在磁异常，这对应于顺磁到反铁磁的有序转变。2 K时磁化强度的场依赖性对应于二维三角形晶格系统中常见的1/3磁化平台。此外，热容测量在2.15 K处发现了一个λ型异常，这就是磁转变温度。这种材料可能是具有诸如自旋液体态等新型磁现象的几何阻挫系统的良好候选者。
