摘要
在Lanl2dz和6-311++G(3df,2pd)不同的基组水平上,采用量子化学方法分别对Zn^(2+)和AlCl^(2+)改性后的NaAlCl_4催化制备(CH_3)_2SiCl_2的反应机理进行了研究。计算结果表明:Zn^(2+)改性NaAlCl_4后速控步骤为催化剂吸附(CH_3)_3SiCl的过程;而AlCl_2^+改性NaAlCl_4后机理中速控步骤为CH_3SiCl_3与催化剂一并吸附(CH_3)_3SiCl所形成的中间体(CH_3AlCl_2/X-ZSM—5)的过程。综合分析得知:两通道的速控步骤活化能相差79.11kJ·mol^(-1),AlCl_2^+有利于反应进行,而Zn^(2+)对反应有负面影响。这与前线轨道分析结果一致。
The preparation of dimethyldichlorosilance catalyzed by NaAlCl4 was calculated through B3LYP /Lan L2dz and 6-311 ＋ ＋ G（ 3df,2pd） approaches. Conclusions are as follows： the rate-determining step of main reaction catalyzed by NaAlCl4/ Zn^2＋-ZSM—5 is the reaction of absorbing trimethylchlorosilane. The rate-determining step of main reaction catalyzed NaAlCl_4/（ AlCl2）^＋-ZSM—5 is the reaction that methyltrichlorosilane absorb intermediate（ CH3AlCl2/（ AlCl2）^＋-ZSM—5）. The activation energies of the two reactions differ by 79. 11 kJ·mol^-1.The introduction of（ AlCl2）^＋is good for reaction running and the Zn^2＋ is not. It matches well with frontier orbital analysis.
出处
《科学技术与工程》
北大核心
2016年第7期1-6,共6页
Science Technology and Engineering
基金
国家自然科学基金(21563011,21163005)
江西省自然科学基金(20132BA203013)资助
关键词
DFT
MP2
机理
硅烷歧化
DFT
MP2
mechanism
silane disproportionation
