从头算及变分过渡态理论研究尿素和甲醛的反应  

Ab initio study on the reaction of urea and formaldehyde with variational transitional state theory

作　　者：马金广[1] 张纪明[2] 周建华[2] 

机构地区：[1]滨州学院化学与化工系 滨州市材料化学重点实验室,山东滨州256603 [2]山东轻工业学院化学与制药工程学院,山东济南250353

出　　处：《计算机与应用化学》2012年第11期1304-1306,共3页Computers and Applied Chemistry

基　　金：滨州学院青年人才创新工程基金资助项目(BZXYQNLG200813)

摘　　要：用从头算方法在MP2／6-31＋G（田水平下研究了尿素和甲醛反应机理，在从头算给出的信息基础上，用变分过渡态理论加小曲率隧道效应计算T（200-3000）K温度范围内尿素和甲醛反应的速率常数。脲与甲醛的反应是较简单的加成反应，反应的基元过程主要是氮氢键的断裂和氧氢键的生成。在MP2／6．31＋G（奶理论水平下，反应的势垒高度为32．83kcal·mol-1。计算的速率常数展示出较强的非Arrhenius行为，速．The reaction mechanism of urea with formaldehyde was investigated by ab initio method at the MP2/6-3 1＋G（d） level. Reaction rate of urea and formaldehyde between （200-3000） K has been studied using the canonical variational transition state theory with the small-curvature tunneling correction method. The reaction of urea with formaldehyde is a simple addition reaction. The elementary processes of this reaction are the breaking of nitrogen-hydrogen bond and the formation of oxygen-hydrogen bond. The forward potential barrier at MP2/6-31 ＋G（d） level is 32.83 kcal-mor1. The result shows that the calculated CVT/SCT rate constants exhibit typical non-Arrhenius behavior. The relativity of rate-temperature can be described as follows： （cm3·moleculel＇sl）.

关 键 词：反应机理 变分过渡态理论 动力学研究 

分 类 号：O641[理学—物理化学]