We have successfully synthesized a new transition metal tellurate compound K₂Cu₂(Te₂O₅)(TeO₃)₂·2H₂O. The compound crystallizes in the monoclinic crystal system with space group P2₁/c; the Te coordination polyhedra polymerizes to form [Te₂O₅]_∞ ladders running along [100]. The ladders are connected in the [001] direction to the [Cu₂O₈] spin-dimer units via common oxygen to form covalently bonded [Cu₂Te₂O₅]_∞. Magnetization measurements confirmed that K₂Cu₂(Te₂O₅)(TeO₃)₂·2H₂O has spin-dimer properties. The broad maximum around T_max = 50 K indicates the low-dimensional magnetic interaction and may be related to the existence of more than one spin dimer in the system. The perfect fitting of Bleaney–Bowers on magnetization curves shows the coexistence of two kinds of Cu–Cu dimers in K₂Cu₂(Te₂O₅)(TeO₃)₂·2H₂O, in which the two dimers show different intradimer and interdimer magnetic interactions resulting from the different Cu–Cu distances and different coordination circumstances. The experimental results indicate the magnetic properties of the dimer can be modulated using the crystalline coordination of the spin dimer.

中文翻译：

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新型自旋二聚体化合物K ₂ Cu ₂（Te ₂ O ₅）（TeO ₃）₂ ·2H ₂ O的合成，结构和磁性

我们已经成功地合成了一种新的过渡金属化合物碲ķ ₂的Cu ₂（TE ₂ ø ₅）（的TeO ₃）₂ ·2H ₂ O的化合物结晶，空间群单斜晶系P 2 ₁ / ç ; Te配位多面体聚合形成沿[100]延伸的[ Te ₂ O ₅ ] _∞梯。梯子通过公共氧沿[001]方向连接到[Cu ₂ O ₈ ]自旋二聚体单元，以形成共价键合的[Cu ₂ Te ₂ O₅ ] _∞。磁化测量证实，K ₂ Cu ₂（Te ₂ O ₅）（TeO ₃）₂ ·2H ₂ O具有自旋二聚体性质。T _max = 50 K附近的宽最大值表示低维磁相互作用，并且可能与系统中存在多个自旋二聚体有关。Bleaney-Bowers在磁化曲线上的完美拟合显示了两种Cu-Cu二聚体在K ₂ Cu ₂（Te ₂ O ₅）（TeO ₃）₂ ·2H _2中共存O，其中两个二聚体显示不同的二聚体和二聚体间的磁性相互作用，这是由不同的Cu-Cu距离和不同的配位环境引起的。实验结果表明，可以使用自旋二聚体的晶体配位来调节二聚体的磁性。