本文对AB_2和AB_3型分子的几何模型变化的规律进行探讨。依关于非(?)合原子间的相互作用是决定键角偏离“正常值”的主要因素这观点,得出一个联系键长、键角和非键合原子的范德华半径的关系的经验公式,这经验公式表明: (1)非键合原子间的相互作用是决定分子空间构型的一个重要因素。 (2)非键合原子的电子云相互重叠程度决定于“中心原子”的性质。 In this paper, the rules of the geometric model changes of AB_2 and AB_3 are discussed. According to the view that the interaction between non-atomic atoms is the main factor that determines the key angle deviates from the “normal” value, an empirical formula is obtained for the relationship between bond length, bond angle and van der Waal’s radius of non-bonded atoms, The empirical formula shows: (1) The interaction between non-bonded atoms is an important factor in determining the spatial configuration of the molecule. (2) The degree of overlap of non-bonded atoms depends on the nature of the “central atom.”