Ethylene, the simplest model of a carbon-carbon double bond system, is pivotal in numerous chemical and biological processes. By employing intense infrared laser pump-probe techniques alongside coincidence measurement...Ethylene, the simplest model of a carbon-carbon double bond system, is pivotal in numerous chemical and biological processes. By employing intense infrared laser pump-probe techniques alongside coincidence measurements, we investigate the ultrafast non-adiabatic dynamics involved in the breakage of carbon-carbon double bonds and hydrogen elimination in dissociation of ethylene. Our study entails analyzing the dynamic kinetic energy release spectra to assess three bond-breaking scenarios, movements of nuclei, and structural changes around the carbon atoms. This allows us to evaluate the relaxation dynamics and characteristics of various dissociative states. Notably, we observe a significant rise in the yield of fragments resulting from C–H bond breakage with the delay time extended, suggesting non-adiabatic coupling through conical intersections from C–C bond breakage as a probable cause.展开更多
The γ-rays with energies up to 300keV have been observed from plasmas produced by femtosecond laser pulses at a focused intensity of 5 × 10^(15) W.cm^(-2).μm^(2) irradiating Ta,Mo,and Cu targets.By introducing ...The γ-rays with energies up to 300keV have been observed from plasmas produced by femtosecond laser pulses at a focused intensity of 5 × 10^(15) W.cm^(-2).μm^(2) irradiating Ta,Mo,and Cu targets.By introducing an 8% prepulse of 70ps before the main pulse,the fraction of high energy γ-ray photons(hv>l00keV)was significantly enhanced relative to low energy photons(hv<100 keV).展开更多
The femtosecond third harmonic generaction(THG)output has been measured from a series of poly(N-vinylcarbazole)(PVK),C_(60),mixed and multilayer PVK/C_(60) films which were all fabricated by physical jet deposition te...The femtosecond third harmonic generaction(THG)output has been measured from a series of poly(N-vinylcarbazole)(PVK),C_(60),mixed and multilayer PVK/C_(60) films which were all fabricated by physical jet deposition technique.There is an enhancement of femtosecond THG output from the mixed PVK/C_(60) film in comparison with other films.Charge transfer complex in the mixed PVK/C_(60) film was considered to be the main reason for this increase of the third-order susceptibility.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 12134005, 92261201, and 12274179)。
文摘Ethylene, the simplest model of a carbon-carbon double bond system, is pivotal in numerous chemical and biological processes. By employing intense infrared laser pump-probe techniques alongside coincidence measurements, we investigate the ultrafast non-adiabatic dynamics involved in the breakage of carbon-carbon double bonds and hydrogen elimination in dissociation of ethylene. Our study entails analyzing the dynamic kinetic energy release spectra to assess three bond-breaking scenarios, movements of nuclei, and structural changes around the carbon atoms. This allows us to evaluate the relaxation dynamics and characteristics of various dissociative states. Notably, we observe a significant rise in the yield of fragments resulting from C–H bond breakage with the delay time extended, suggesting non-adiabatic coupling through conical intersections from C–C bond breakage as a probable cause.
基金Supported by the National Natural Science Foundation of China under Grant No.19854001the National High Technology ICF Committee under Grant No.416-3.
文摘The γ-rays with energies up to 300keV have been observed from plasmas produced by femtosecond laser pulses at a focused intensity of 5 × 10^(15) W.cm^(-2).μm^(2) irradiating Ta,Mo,and Cu targets.By introducing an 8% prepulse of 70ps before the main pulse,the fraction of high energy γ-ray photons(hv>l00keV)was significantly enhanced relative to low energy photons(hv<100 keV).
文摘The femtosecond third harmonic generaction(THG)output has been measured from a series of poly(N-vinylcarbazole)(PVK),C_(60),mixed and multilayer PVK/C_(60) films which were all fabricated by physical jet deposition technique.There is an enhancement of femtosecond THG output from the mixed PVK/C_(60) film in comparison with other films.Charge transfer complex in the mixed PVK/C_(60) film was considered to be the main reason for this increase of the third-order susceptibility.
