According to quantum mechanics,the essence of molecular field is the magnetic order caused by inter-electronic reciprocal interchange of contiguous atoms,so its essence is static electrification.
Weiss"分子场"理论是解释自发磁化的经典理论,却不能说明"分子场"的本质,量子力学研究认为"分子场"的本质是相邻原子中电子间的相互交换作用导致的磁有序,因此,"分子场"的本质是静电作用。