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化学反应活化络合物理论（又称过渡状态理论或绝对速度理论）认为，在一切化学反应动力学过程中首先必须经历一过渡状态，生成一不稳定的活化给合物，然后，活化络合物沿反应轴方向振动，即分解为反应产物。可表示为如下一般程式：上式中Ａ、Ｂ及、Ｃ、Ｄ分别表示反应物及产物，［ＡＢ］＿≠代表反应经历过渡状态所生成的不稳定活化络合物。该理论进一步认为，生成活化络合物的步骤与该络合物振动分解步骤相比为极快步骤。因此，该理论假定反应物与活化络合物之间处于平衡状态之中（活化络合平衡常数以Ｋ＿≠表示），反应速度完全决定于活化络合物的振动频率ｕ＿≠，可根据对应的振动能ｈｕ＿≠（ｈ为ｐｌａｎｋ常数）遵从平衡态能量按自由度均等分布定律加以推算。从而可得反应速度Ｖ之理论表达式式中：Ｃ＿Ａ，Ｃ＿Ｂ及Ｃ＿≠分别表示反应物Ａ、Ｂ及活化络合物之浓度，ｋ＿Ｂ及Ｔ表示Ｂｏｌｔｚｍａｎｎ常数及温度，这就是反应速度的质量作用定律表示式。活化络合物理论揭示反应速度常数为ｋ＿－１，与Ｋ＿≠有关，可通过标准态活化络合物生成焓及生成熵△Ｓ°≠加以推算这一理论结论与实验结果基本吻合，但也有不少情况出现较大的偏差。这很可能来自该理论的若干简化假定，过分近似地引用了平衡?
Chemically activated complex theory (also known as transition state theory or absolute velocity theory) that in all chemical reaction kinetics must first go through a transitional state to generate an unstable activated compound, and then activated complex The material vibrates along the reaction axis, ie decomposes into reaction products. Can be expressed as the following general formula: In the above formula, A, B and, C, D, respectively, reactants and products, [AB] _ ≠ representatives of the transition state reaction generated unstable activated complex. This theory further suggests that the step of generating an activated complex is an extremely fast step as compared to the step of vibrational decomposition of the complex. Therefore, the theory assumes that the reactant and the activated complex are in a state of equilibrium (activation complex equilibrium constant is expressed as K_ ≠), and the reaction speed is completely determined by the vibration frequency u_ ≠ of the activated complex. According to the correspondence The vibration energy hu_ ≠ (h is the plank constant) follow the equilibrium state energy according to the law of equal degree of freedom distribution to be calculated. Thus, the theoretical expression for the reaction rate V is: C_A, C_B and C_ ≠ denote the concentrations of the reactants A and B and the activated complex, respectively, k_B and T denote the Boltzmann constant and the temperature, and this is the mass effect of the reaction rate The law of expression. Activation complex theory reveals that the reaction rate constant is k_-1, which is related to K_ ≠, and can be deduced from the enthalpy of formation and entropy △ S ° ≠ of the activation energy of the standard state. The theoretical conclusion is in good agreement with the experimental results. However, In many cases there is a big deviation. This is likely to come from a number of simplifying assumptions of the theory that invoke the balance too closely?