摘要
采用量子力学与分子力学组合的ONIOM方法,研究限域在扶手椅型单壁氮化硼纳米管(SWBNNT)内赖氨酸(Lys)分子手性转变的反应机理.采用原子中心密度矩阵传播(ADMP)分子动力学方法,研究Lys分子在SWBNNT(5,5)内手性转变反应通道入口与出口势能面上的动态反应路径,给出中间体和产物的微观动态反应图像.结果表明:随着纳米管管径的减小,限域其中的Lys分子骨架C原子间的键角明显增大;手性C上的H与氨基N的距离逐渐变小;在SWBNNT(5,5)内,通过2个基元反应Lys分子实现了手性转变;在SWBNNT(6,6)和SWBNNT(7,7)内,通过3个和4个基元反应Lys分子实现了手性转变;在SWBNNT(5,5)内,Lys分子手性转变反应决速步骤自由能垒降为最低值190.1kJ/mol.在SWBNNT(7,7)内,决速步骤能垒与裸反应基本相同.
Using the ONIOM methods by combining quantum mechanics and molecular mechanics, we studied the reaction mechanism of the chiral transition of lysine (Lys) molecules confined in the armchair single walled boron nitride nanotube (SWBNNT). Using atom centered density matrix propagation (ADMP) molecular dynamics methods, we studied Lys molecules in the SWBNNT(5,5) dynamic reaction path in the inlet and outlet of the potential energy surface in chiral transition reaction channel, and gave images of the microscopic dynamic reaction of intermediates and products. The results show that with the decrease of diameter of nanotube, the bond angle between the skeletal carbon atoms of Lys molecules confined in nanotubes increases obviously, and the distance between H and amino N on chiral carbon gradually becomes smaller. The chiral transition of Lys molecules is achieved by a two-step elementary reaction in SWBNNT(5,5), whereas it is achieved by the three- step and four-step elementary reactions in SWBNNT (6,6) and SWBNNT (7,7), respectively. The free energy barrier of the rate-determining step of Lys molecule chiral transition reaction is reduced to a minimum value of 190.1 kJ/mol in SWCNT(5,5). The energy barrier of the rate-determining step is similar to that of bare reaction in SWBNNT(7,7).
作者
董丽荣
刘逸轩
高峰
闫红彦
王佐成
DONG Lirong LIU Yixuan GAO Feng YAN Hongyan WANG Zuocheng(College of Physics, J ilin Normal University, Si ping 136000, J ilin Province, China Natural Science Instruction, Haikou College of Economics, Haikou 570100, China College of Physics and Electronic Information, Baicheng Normal University, Baicheng 137000, Jilin Province, China College of Computer Science, Baicheng Normal University, Baicheng 137000, Jilin Province, China)
出处
《吉林大学学报(理学版)》
CAS
CSCD
北大核心
2017年第2期435-443,共9页
Journal of Jilin University:Science Edition
基金
吉林省自然科学基金(批准号:20160101308JC)