Collision-induced dissociation of 2- and 3-dimensional polycyclic aromatic hydrocarbon cations in a modified ion-trap detector
Collision-induced dissociation of 2- and 3-dimensional polycyclic aromatic hydrocarbon cations in a modified ion-trap detector
复制标题
DOI：
10.1016/s0168-1176(96)04430-8
复制
发表时间：
1997-02-01
期刊：
影响因子：
--
通讯作者：
Bohme, DK
中科院分区：
文献类型：
--
作者：
Wang, XM;Becker, H;Bohme, DK
采用一种改进的Finnigan MAT离子阱检测器，系统地研究了碳含量在10 ~ 24个碳原子之间的2维和3维多环芳烃（PAH）阳离子的碰撞解离：萘、苊、苊、菲、蒽、芘、环烯和冕烯。这些阳离子由电子撞击产生，用单极共振激发激发50 ms，然后用氩气碰撞激活解离。用这种方法得到的萘阳离子碎裂结果与光解得到的结果的比较表明，使用离子阱方法可以在离子中沉积相当数量的内能，大于或等于7.3 eV。对于所有多环芳烃阳离子，C-H键比C-C键更有利于裂解。在蒽、菲和环烯中，C-C有明显的裂解，（2C,2H）、（2C,3H）和（2C,4H）被消除。除苊和环烯阳离子外，更大的多环芳烃阳离子对断裂更稳定。苊离子是最稳定的。相对于相关的二维芘和冠烯分子的阳离子，三维应变冠烯分子的阳离子表现出更高的断裂效率。提出了该阳离子解离的机理途径。(C) 1997爱思唯尔科学有限公司
A modified Finnigan MAT ion-trap detector has been employed in a systematic examination of the collisional dissociation of the cations of selected 2- and 3-dimensional polycyclic aromatic hydrocarbons (PAH) with a carbon content ranging from 10 to 24 carbon atoms: naphthalene, acenaphthylene, acenaphthene, phenanthrene, anthracene, pyrene, corannulene and coronene. The cations were produced by electron impact, excited for 50 ms using monopolar resonant excitation, and then dissociated by collisional activation with argon collision gas. A comparison of the results obtained in this way for the naphthalene cation fragmentation with results obtained by photodissociation show that appreciable amounts of internal energy, greater than or equal to 7.3 eV, could be deposited in the ion using the ion-trap method. C-H bond cleavage was favoured over C-C bond cleavage for all PAH cations. Significant C-C cleavage with elimination of (2C,2H), (2C,3H) and (2C,4H) was observed with anthracene, phenanthrene and corannulene. With the exception of the cations of acenaphthylene and corannulene, larger PAH cations were observed to be more stable against fragmentation. The acenaphthylene cation was the most stable. The cation of the 3-dimensional, strained corannulene molecule exhibited an enhanced fragmentation efficiency relative to the cations of the related 2-dimensional pyrene and coronene molecules. Mechanistic pathways are proposed for the dissociation of this cation. (C) 1997 Elsevier Science B.V.