Altermagnetism is introduced as a category of magnetic states with ‘collinear’ antiferromagnetic spins and alternating variations of local structures around spins in such a way that the symmetry allows typical ferromagnetic behaviors. Altermagnets exhibiting ferromagnetic behaviors without any external perturbations (type-I) turn out to belong to the ferromagnetic point group. Other altermagnets (type-II and type-III) can have ferromagnetic behaviors only with external perturbations such as electric current or stress, which conserve parity-time-reversal (PT) symmetry. All types of altermagnets themselves have broken PT symmetry. The concept of altermagnetism can be extended to accommodate non-collinear spins and multiple local-structure variations.

交变磁性是作为一类磁态引入的，具有“共线”反铁磁自旋和自旋周围局部结构的交替变化，使得对称性允许典型的铁磁行为。在没有任何外部扰动的情况下表现出铁磁行为的交变磁体（I 型）被证明属于铁磁点群。其他交流磁体（II 型和 III 型）仅在电流或应力等外部扰动下才具有铁磁行为，从而保持宇称时间反转 (PT) 对称性。所有类型的交流磁体本身都具有破缺的 PT 对称性。交变磁性的概念可以扩展到适应非共线自旋和多种局部结构变化。