ABSTRACT The magnetic properties (phase diagram, the thermal variations of magnetization and the reduced magnetization curve) in graphene-like Ising nanoparticles are examined by the effective-field theory with correlations. The effects of surface exchange interaction JS on the magnetic properties are discussed. When JS is larger than the critical value JSC, a nanoparticle with high critical temperature is possible. The value of JSC depends on the shape and the degree of structural packing of the nanoparticle. It is found that there exist two types of reduced magnetization curves for a nanoparticle with JS > JSC.

中文翻译：

---

Ising 纳米粒子在高临界温度下的磁化曲线

摘要 类石墨烯 Ising 纳米粒子的磁性（相图、磁化热变化和磁化强度曲线）通过有效场理论与相关性进行了检查。讨论了表面交换相互作用 JS 对磁性能的影响。当 JS 大于临界值 JSC 时，具有高临界温度的纳米颗粒是可能的。JSC 的值取决于纳米颗粒的形状和结构堆积程度。发现JS>JSC的纳米颗粒存在两种磁化曲线。