HgCl_2和PdCl_2催化乙炔与氯化氢反应机理的研究

Reaction Mechanism Research on Acetylene and Hydrogen Chloride Catalyzed by HgCl_2 and PdCl_2

采用B3LYP方法分别对无催化剂,Hg Cl2、Pd Cl2为催化剂条件下乙炔氢氯化反应的机理进行研究.使用6-311+G(d,p)基组(Hg、Pd采用赝势基组Lan L2DZ)对乙炔氢氯化反应过程中所有反应物、过渡态、中间体以及产物的几何构型进行优化.同时进行频率计算,各过渡态都有唯一虚频,确认了中间体和过渡态的合理性;通过自然键轨道(NBO)理论和AIM理论分析分子轨道间的相互作用.发现以Hg Cl2、Pd Cl2为催化剂的条件下乙炔氢氯化反应的机理不一样,Pd Cl2的催化性能比Hg Cl2的催化性能好.

By means of B3LYP, we considered the mechanism of the hydrochlorination of acetylene under no catalyzer conditions and under the conditions of HgCl2 and PdCl2. With the basis set level of 6-311 ＋ G（ d, p） （Hg and Pd using the pseudo potential basis set of LanL2DZ）, the configurations of all the reactants, transient states, intermediates and products of hydrochlorination of acetylene were optimized. Meanwhile, we calculated the frequency and found out that all the transient state had the only imaginary frequency. Moreover, the rationality of intermediates and transient state was confirmed. We analyzed the interaction among molecular orbits via NBO and AIM. The mechanism of the hydrochlorination of acetylene is different under the conditions of HgCl2 and PdCl2, respectively. The catalytic properties of PdCl2 are more efficient than that of HgCl2.