Dissociation Dynamics of O+ Formation Channels from Vibrational State-Selected NO2+ at e(3)B(2) State

作者：Niu Ming Li; Song Lei; Tang Xiao Feng; Zhou Xiao Guo^*; Liu Shi Lin; Liu Fu Yi; Shan Xiao Bin; Sheng Liu Si

来源：Acta Physico - Chimica Sinica, 2011, 27(8): 1797-1802.

• Dissociation dynamics
• Photoionization
• Threshold photoelectron spectrum
• Photoelectron-photoion coincidence
• Velocity map imaging

The dissociation dynamics of vibrational state-selected NO2+(e(3)B(2)) was investigated using threshold photoelectron-photoion coincidence velocity imaging and photoionization by synchrotron radiation. The vibrational resolution threshold photoelectron spectrum of NO2+(e(3)B(2)) was recorded in the energy range of 18.8-19.2 eV and was consistent with previous measurements. Furthermore, the coincident velocity images of the O+ fragments that dissociated from the (0,0,0) and (1,0,0) vibronic levels of NO2+(e(3)B(2)) showed a multi-ring structure, indicating that O+ fragments with different speeds were produced during dissociation as well as corresponding NO molecules with different internal energy distributions. The total kinetic energy released distributions and the angular distributions of O+ during dissociation were obtained subsequently from the images. The internal energy distributions of the NO (X-2 Pi)fragments that dissociated from the two vibrational states of NO2+(e(3)B(2)) were very similar and consisted of 3-5 dominant populated vibronic levels. The available energy released from dissociation was found to be almost evenly distributed between the kinetic and internal energies of the fragments and, specifically, a total kinetic energy of 52% and an internal energy of 48% were obtained. In addition, the anisotropy parameter, beta, of the O+ fragments was about 0.3 and was hardly dependent on the vibrational quantum number of the NO(X-2 Pi) fragment.

• 出版日期2011-8
• 单位中国科学技术大学