Department of Physical Chemistry, School of Chemistry, The University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
J Chem Phys. 2011 Jan 21;134(3):031103. doi: 10.1063/1.3544211.
Delayed asymmetric Coulomb fission in size-selected molecular dication clusters has been recorded for the first time. Observations on (NH(3))(n)(2+) clusters show that fragmentation accompanied by charge separation can occur on a microsecond time scale, exhibits considerable asymmetry, and involves a kinetic energy release of ∼0.9 eV. The fission process has been modeled by representing the fragments as charged dielectric spheres and the calculated maximum in the electrostatic interaction energy between the fragments gives a good account of the measured kinetic energy release. A simple kinetic model shows that instrumental factors may contribute to the observation of asymmetric fragmentation.
首次记录到尺寸选择的分子二价阳离子团簇中的延迟非对称库仑裂变。对(NH3)n(2+)团簇的观察表明，伴随着电荷分离的碎裂可以在微秒时间尺度上发生，表现出相当大的不对称性，并涉及约 0.9 eV 的动能释放。通过将碎片表示为带电介电球体来模拟裂变过程，并且碎片之间的静电相互作用能的计算最大值很好地解释了测量的动能释放。一个简单的动力学模型表明，仪器因素可能导致观察到非对称碎裂。
