(H)FNO^+异构体的结构及异构化反应的量子化学研究  

Theoretical Studies on the Structures and Isomerization of(H)FNO^+

作　　者：李晓艳[1] 曾艳丽[1] 王月兰[1] 孟令鹏[1] 郑世钧[1] 

机构地区：[1]河北师范大学化学与材料科学学院,石家庄050016

出　　处：《化学学报》2010年第22期2278-2284,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.20973053;20771033;20801017);河北省自然科学基金(Nos.B2008000141;B200800138);河北省教育厅基金项目(Nos.2007123;2009137);河北师范大学基金(Nos.L2008B06;L2009Y06)资助项目

摘　　要：在CCSD(T)/6-311+G(2d,2p)//B3LYP/6-311+G(2d,2p)水平上对八种(H)FNO+异构体的结构和异构化机理进行了研究.用分子生成密度差结合电子密度拓扑分析方法讨论了FNO质子化过程中的电子转移,结果显示FNO质子化过程中除HFNO+中电荷由N,O原子向H,F原子转移外,其他七种异构体中均是H原子上电荷增加,F原子上电荷减小,说明电子由F向H转移.在八种(H)FNO+异构体中,HFNO+,FNOH-cis,FN(H)O+和FNOH+-trans能量较低,较稳定;异构体间通过H原子迁移、F原子迁移、分子内化学键转动及化学键的相对振动四种过程实现异构化,其中原子迁移过程的反应能垒很高,反应不容易进行.用电子定域函数(ELF)理论讨论了反应过程中化学键的变化.The structures and isomerization mechanisms of eight（H）FNO＋ isomers have been studied at CCSD（T）/6-311＋G（2d,2p）//B3LYP/6-311＋G（2d,2p） levels.The molecular formation density difference（MFDD） and the topological analysis of electron density theory were used to discuss the electron transfer in the protonated processes of FNO,the results show that expect for HFNO＋,the electron transfers from N,O atom to H,F atom,the other seven isomers,the electron density of H increased and that of F atom decreased,which means that the electron transfers from F atom to H atom.Among the eight isomers,HFNO＋,FNOH-cis,FN（H）O＋and FNOH＋-trans are the stable species because of their lower energies.The isomerizations of（H）FNO＋could be achieved by the migration of H atom or F atom,the rotation or vibration of chemical bond.Because the atom migration mechanism has the higher energy barrier,it could not achieve easily.The chemical bonds changes on the reaction paths are described by electron localization function（ELF）.

关 键 词：异构化反应 电子密度拓扑分析 分子生成密度差 电子定域函数 

分 类 号：O641.1[理学—物理化学]