金属Ti原子与卤代甲烷的气相反应研究  

Chemical Reactions of Laser Ablated Ti Atom with Halomethanes in Gas Phase

作　　者：梁彬勇[1] 张勇[1] 辜振宁[1] 秦启宗[1] 

机构地区：[1]复旦大学激光化学研究所,上海200433

出　　处：《高等学校化学学报》1997年第9期1523-1526,共4页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金

摘　　要：利用带分子束装置的飞行时间质谱技术研究了激光溅射金属Ti原子与CF4、CF3Br、CF3Cl、CCl4的气相反应．激光电离飞行时间质谱检测结果表明，Ti原子与前3种含氟的卤代甲烷反应只生成TiF，而与CCl4反应时则生成了TiCl．可认为这类反应是通过电子转移机理进行的，Ti原子与三氟卤代甲烷反应时先形成［Ti+...F-─CF2X」离子对中间体，然后生成产物TiF．The gas-phase reactions between laser ablated Ti atom and four different kinds ofhalomethane (CF4, CF3Br, CF3Cl, CCl4) were studied by a home-made tlme-of-fIight massspectrometer (TOF-MS) coupled wlth a pulse molecular beam device. A pulsed laser beam at532 nm was employec1 to ablate a tltanlum target and generate the metal Ti atoms, whichwill react with a pulsed supersonic molecular beam of halomethane using Ar as a carrier gas.The neutral products were detected by laser nonresonance photoionization with 266 nm pho-tons and timech-of-flight (TOF) mass spectrometry. The measured TOF mass spectra showthat only TiF is formed in the reactions of Ti atom with CF4, CF3Br and CF3Cl, while TiCl isformed in the reaction of Ti atom with CCl4. Our results can be explained in terms of an elec-tron transfer mechanism via an ion-pair complex, such as:Ti+CF3X→[Ti+...F- -CF2X] → TiF + CF2X

关 键 词：卤代甲烷 电子转移机理 钛 气相反应 质谱 

分 类 号：O614.411[理学—无机化学] O623.21[理学—化学]