电负性是分子中一个原子把电子拉向它自身的能力,是化学理论的基本概念之一。继Pauling建立第一个电负性标度后,提出了众多的电负性标度。只是在密度泛函理论的基础上,电负性概念和电负性均衡原理,才被精密地论证。近二十多年来,电负性理论的重要发展是:应用电负性均衡模型或方法,可以快速地计算分子体系的电荷分布,从而确定分子的其他性质,甚至包括分子的结构和反应性指标。通常的电负性均衡方法只把分子划分到原子区域,虽然简单直观,但其精度和应用范围受到限制。原子与键电负性均衡方法,把分子划分到包括原子区域、化学键区域和孤对电子区域,能够较快速精密地计算分子的电荷分布和其他性质,并被应用到构建新一代可极化或浮动电荷力场的探索中,有广阔的应用前景。 Electronegativity is the ability of an atom in a molecule to pull an electron toward itself, and is one of the basic concepts of chemical theory. Following Pauling’s establishment of the first electronegativity scale, a number of electronegativity scales have been proposed. Only on the basis of density functional theory, the concept of electronegativity and the principle of electronegativity equalization have been precisely demonstrated. For more than two decades, an important development of electronegativity theory is that the electronegativity equilibrium model or method can be used to quickly calculate the charge distribution of a molecular system to determine other properties of the molecule, including even the structure and reactivity of the molecule index. The usual method of electronegativity equalization only divides the molecules into atomic regions. Although simple and intuitive, its accuracy and application range are limited. Atom and bond electronegativity equalization method, the molecules are divided into areas including atoms, chemical bonds and lone pairs of electronic regions, the molecules can be more quickly and accurately calculated charge distribution and other properties, and is applied to the construction of a new generation of polarizable or Floating charge field exploration, a broad application prospects.