Using a neutral N2 beam as target, this paper studies the dissociation of N2^＋ in intense femtosecond laser fields （45 fs, ～ 1 × 10^16 W/cm^2） at the laser wavelength of 800 nm based on the time-of-flight mas...Using a neutral N2 beam as target, this paper studies the dissociation of N2^＋ in intense femtosecond laser fields （45 fs, ～ 1 × 10^16 W/cm^2） at the laser wavelength of 800 nm based on the time-of-flight mass spectra of N＋ fragment ions. The angular distributions of N^＋ and the laser power dependence of N^＋ yielded from different dissociation pathways show that the dissociation mechanisms mainly proceed through the couplings between the metastable states （A, B and C） and the upper excited states of N^＋.A coupling model of light-dressed potential energy curves of N2^＋ is used to interpret the kinetic energy release of N^＋.展开更多
Using geometrical optimization and DFT method at the B3LYP/6-31G （d） level, nineteen equilibrium geometries were identified, and three transition states of dissociation reaction of C3O6 clusters were also found. The...Using geometrical optimization and DFT method at the B3LYP/6-31G （d） level, nineteen equilibrium geometries were identified, and three transition states of dissociation reaction of C3O6 clusters were also found. The vibrational frequencies and intrinsic reaction coordinate （IRC） verification at the same level were computed to verify the transitions. And then we calculated the dissociation energies and analyzed the dissociation channels. The computational results show that the dissociation energies of C3O6 isomers relative to three CO2 are between 1.509 × 103 and 10.61 × 10^3 kJ·kg^-1, and the energy barriers of the reactions are 92.857, 131.138 and 185.793 kJ·mol^-1. Both the high dissociation energies and high energy barriers show that C3O6 clusters studied in this paper are stable enough to be used as high-energy-density materials.展开更多
Considering the feature of distributions of parameters within the micro-hollow cathode discharge, we use a simple method to separate the sheath region characterized by drastic changes of plasma parameters and the bulk...Considering the feature of distributions of parameters within the micro-hollow cathode discharge, we use a simple method to separate the sheath region characterized by drastic changes of plasma parameters and the bulk plasma region characterized by smooth changes of plasma parameters. A zero-dimensional chemical kinetic model is used to analyze the dissociation mechanism of CO2 in the bulk plasma region of a micro-hollow cathode discharge and is validated by comparisons with previous modeling and experimental results. The analysis of the chemical kinetic processes has shown that the electron impact dissociation and heavy species impact dissociation are dominant in different stages of the rnicro-hollow cathode discharge process for a given applied voltage. The analysis of energy consumption distributions under different applied voltages reveals that the main reason of the conversion improvement with the increase of the applied voltage is that more input energy is distributed to the heavy species impact dissociation.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10774033,60878018 and 10674036)program for New Century Excellent Talents in University of China (NCET)
文摘Using a neutral N2 beam as target, this paper studies the dissociation of N2^＋ in intense femtosecond laser fields （45 fs, ～ 1 × 10^16 W/cm^2） at the laser wavelength of 800 nm based on the time-of-flight mass spectra of N＋ fragment ions. The angular distributions of N^＋ and the laser power dependence of N^＋ yielded from different dissociation pathways show that the dissociation mechanisms mainly proceed through the couplings between the metastable states （A, B and C） and the upper excited states of N^＋.A coupling model of light-dressed potential energy curves of N2^＋ is used to interpret the kinetic energy release of N^＋.
基金Supported by the Natural Science Foundation of Shandong Province (No. Y2006B24 and Y2008B33)
文摘Using geometrical optimization and DFT method at the B3LYP/6-31G （d） level, nineteen equilibrium geometries were identified, and three transition states of dissociation reaction of C3O6 clusters were also found. The vibrational frequencies and intrinsic reaction coordinate （IRC） verification at the same level were computed to verify the transitions. And then we calculated the dissociation energies and analyzed the dissociation channels. The computational results show that the dissociation energies of C3O6 isomers relative to three CO2 are between 1.509 × 103 and 10.61 × 10^3 kJ·kg^-1, and the energy barriers of the reactions are 92.857, 131.138 and 185.793 kJ·mol^-1. Both the high dissociation energies and high energy barriers show that C3O6 clusters studied in this paper are stable enough to be used as high-energy-density materials.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11575019 and 11275021
文摘Considering the feature of distributions of parameters within the micro-hollow cathode discharge, we use a simple method to separate the sheath region characterized by drastic changes of plasma parameters and the bulk plasma region characterized by smooth changes of plasma parameters. A zero-dimensional chemical kinetic model is used to analyze the dissociation mechanism of CO2 in the bulk plasma region of a micro-hollow cathode discharge and is validated by comparisons with previous modeling and experimental results. The analysis of the chemical kinetic processes has shown that the electron impact dissociation and heavy species impact dissociation are dominant in different stages of the rnicro-hollow cathode discharge process for a given applied voltage. The analysis of energy consumption distributions under different applied voltages reveals that the main reason of the conversion improvement with the increase of the applied voltage is that more input energy is distributed to the heavy species impact dissociation.
