Classically, stable covalent bonding cannot occur between heavy metal cations and clay surface O atoms. However, the classical theory ignores the effect of the electric field arising from clay surface charges on the orbitals of surface O atoms. This article studies the adsorption behavior of heavy metal cations (Pb²⁺, Cd²⁺, Cu²⁺, and Zn²⁺) on charged montmorillonite surfaces from a new theoretical foundation based on the quantum mechanics analysis of surface O atoms in this electric field, which reveals that polarization-induced covalent bonding is a strong adsorption force. The strength of polarization-induced covalent bonding can be controlled by regulating the energy of the lone-pair electrons of surface O atoms, which depends on solution pH, electrolyte type, electrolyte concentration, temperature or dielectric constant of medium, etc. The mathematic relationship between the energy of lone-pair electrons of surface O atoms and electric field arising from surface charges was established through quantum mechanics analysis; and correspondingly the mathematical relationship between the polarization-induced covalent bonding energy and surface potential also was established for different heavy metal cations. The finding of the new adsorption force will have important impact on both theoretical research and removal/deactivation approaches of heavy metal cations.

通常，重金属阳离子与粘土表面的O原子之间不会发生稳定的共价键。但是，经典理论忽略了由粘土表面电荷产生的电场对表面O原子轨道的影响。本文研究了重金属阳离子（Pb 2 ⁺，Cd 2 ⁺，Cu ²⁺和Zn ²⁺）在基于此电场中表面O原子的量子力学分析的新理论基础上对带电荷的蒙脱石表面进行了研究，结果表明极化诱导的共价键是很强的吸附力。极化诱导的共价键的强度可以通过调节表面O原子的孤对电子的能量来控制，这取决于溶液的pH值，电解质类型，电解质浓度，介质的温度或介电常数等。数学关系通过量子力学分析建立了表面O原子孤对电子的能量与表面电荷产生的电场之间的关系。建立了不同重金属阳离子极化诱导的共价键能与表面势之间的数学关系。新吸附力的发现对理论研究和重金属阳离子的去除/失活方法都将产生重要影响。