The gaseous reaction of CH+NO 2 has been investigated experimentally. CH radical was generated by multiple photon photolysis of CHBr 3 at 248 nm. Vibrationally excited species of HCO (ν 3), CO( v ), CO 2 (ν 3), HNO ...The gaseous reaction of CH+NO 2 has been investigated experimentally. CH radical was generated by multiple photon photolysis of CHBr 3 at 248 nm. Vibrationally excited species of HCO (ν 3), CO( v ), CO 2 (ν 3), HNO (ν 1), OH( v ) were detected as emitters of CH+NO 2 reaction by time resolved Fourier transform spectroscope. Three exothermic reaction channels leading to HCO+NO, NH+CO 2, CO+HNO, are identified. The minor reaction leading to OH+NCO may also occur.展开更多
The product channels and mechanisms of the C2HC12+O2 reaction are investigated by step-scan time-resolved Fourier transform infrared emission spectroscopy and the G3MP2// B3LYP/6-311G(d,p) level of electronic struc...The product channels and mechanisms of the C2HC12+O2 reaction are investigated by step-scan time-resolved Fourier transform infrared emission spectroscopy and the G3MP2// B3LYP/6-311G(d,p) level of electronic structure calculations. Vibrationally excited products of HCI, CO, and CO2 are observed in the IR emission spectra and the product vibrational state distribution are determined which shows that HCI and CO are vibrationally excited with the nascent average vibrational energy estimated to be 59.8 and 51.8 kJ/mol respectively. In combination with the G3MP2//B3LYP/6-311G(d,p) calculations, the reaction mechanisms have been characterized and the energetically favorable reaction pathways have been suggested.展开更多
The free radical of CICOCO has been investigated theoretically and experimentallyGeometry、vibrational frequencies and dissociative energy barrier of the ground state of CICOCOwere obtained by ab initio calculations. ...The free radical of CICOCO has been investigated theoretically and experimentallyGeometry、vibrational frequencies and dissociative energy barrier of the ground state of CICOCOwere obtained by ab initio calculations. By 351 nm photolysis of (CICO)2, CICOCO’s infraredendssion at 1844 cm-1 was recorded by TRFTIR spectrometer.展开更多
Time-resolved Fourier transform infrared emission spectroscopy is employed for studing gaseous reaction of CH3 with NO. The CH3 radical was produced by laser photolysis of CH3Br at 248 nm. The infrared emissions of ...Time-resolved Fourier transform infrared emission spectroscopy is employed for studing gaseous reaction of CH3 with NO. The CH3 radical was produced by laser photolysis of CH3Br at 248 nm. The infrared emissions of vibrationally excited nascent products HCO (n3), HCN (n1, n3), NH2 (n3), secondary product HNO (n1) and possible product HNCO (n1) were observed. It verifies that the reaction channels of HCO + NH2 and HCN+H2O exist, and that one other channel HNCO + H may also occur.展开更多
The environmentally important free radical reaction of chlorinated methyl CHCl2 with NO2 was investigated by step-scan time-resolved FTIR (TR-FTIR) emission spectroscopy. Vibrationally excited products of CHClO, NO,...The environmentally important free radical reaction of chlorinated methyl CHCl2 with NO2 was investigated by step-scan time-resolved FTIR (TR-FTIR) emission spectroscopy. Vibrationally excited products of CHClO, NO, CO, and HCl are observed in the high-resolution IR emission spectra and three possible reaction channels are therefore elucidated. In particular, the product CO is newly detected and the product HCl is identified explicitly as a yield from the CHCl2+NO2 reaction, taking advantage of the sensitive detection of HCl and CO with TR-FTIR. These results are of particular interests to understand the related realistic chemical processes including atmospheric photochemistry, biofuel combustion, waste destruction, and smoking fire.展开更多
The reaction of methylene radicals in their 3 B1 electronic ground state with molecular NO was studied. Pure CH2(X 3 B1 ) radicals were prodced by UV photolysis of ketene at 351 nm.The products were measured by Time-R...The reaction of methylene radicals in their 3 B1 electronic ground state with molecular NO was studied. Pure CH2(X 3 B1 ) radicals were prodced by UV photolysis of ketene at 351 nm.The products were measured by Time-Resolved Fourier Transform Infrard (TR-FTIR) spectrometer. CO.OH .NH2 and HOCN or its isomer HNCO were found as primary prodcts and several possible channels of this reaction were suggested.展开更多
The 193 nm photodissociation dynamics of CH2CHCOC1 in the gas phase has been examined with the technique of time-resolved Fourier transform infrared emission (TR-FTIR) spectroscopy. Vibrationally excited photofragme...The 193 nm photodissociation dynamics of CH2CHCOC1 in the gas phase has been examined with the technique of time-resolved Fourier transform infrared emission (TR-FTIR) spectroscopy. Vibrationally excited photofragments of CO (v ≤ 5), HC1 (v ≤ 6), and C2H2 were observed and two photodissociation channels, the C-C1 fission channel and the HC1 elimina- tion channel have been identified. The vibrational and rotational state distributions of the photofragments CO and HC1 have been acquired by analyzing their fully rotationally resolved v→ v- 1 rovibrational progressions in the emission spectra, from which it has been firmly established that the mechanism involves production of HC1 via the four-center molecular elimination of CH2CHCOC1 after its internal conversion from the S1 state to the So state. In addition to the dominant C--C1 bond fission along the excited S1 state, the S1→S0 internal conversion has also been found to play an important role in the gas phase photolysis of CH2CHCOC1 as manifested by the considerable yield of HC1.展开更多
The elementary reaction between allyl radical with oxygen molecule was experimentally investigated. The allyl radical was produced via laser photolysis of C3H5Br in gaseous phase. Nascent vibrational excited products ...The elementary reaction between allyl radical with oxygen molecule was experimentally investigated. The allyl radical was produced via laser photolysis of C3H5Br in gaseous phase. Nascent vibrational excited products HCO, CO2, CH3CHO and HCOOH were recorded by the time- resolved Fourier transform infrared spectroscopy. The product channels of C2H5+CO2, CH3CHO+HCO, and HCOOH + C2H3 have been identified. The vibrational populations of product CO2 are obtained by spectral simulation. A mechanism forming a series of three-membered ring-struc- ture intermediates is suggested.展开更多
文摘The gaseous reaction of CH+NO 2 has been investigated experimentally. CH radical was generated by multiple photon photolysis of CHBr 3 at 248 nm. Vibrationally excited species of HCO (ν 3), CO( v ), CO 2 (ν 3), HNO (ν 1), OH( v ) were detected as emitters of CH+NO 2 reaction by time resolved Fourier transform spectroscope. Three exothermic reaction channels leading to HCO+NO, NH+CO 2, CO+HNO, are identified. The minor reaction leading to OH+NCO may also occur.
基金V. ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.20733005, No.20673126, and No.20973179), the National Basic Research Program of China (No.2007CB815200 and No.2007AA02Z116), and the Chinese Academy of Sciences.
文摘The product channels and mechanisms of the C2HC12+O2 reaction are investigated by step-scan time-resolved Fourier transform infrared emission spectroscopy and the G3MP2// B3LYP/6-311G(d,p) level of electronic structure calculations. Vibrationally excited products of HCI, CO, and CO2 are observed in the IR emission spectra and the product vibrational state distribution are determined which shows that HCI and CO are vibrationally excited with the nascent average vibrational energy estimated to be 59.8 and 51.8 kJ/mol respectively. In combination with the G3MP2//B3LYP/6-311G(d,p) calculations, the reaction mechanisms have been characterized and the energetically favorable reaction pathways have been suggested.
文摘The free radical of CICOCO has been investigated theoretically and experimentallyGeometry、vibrational frequencies and dissociative energy barrier of the ground state of CICOCOwere obtained by ab initio calculations. By 351 nm photolysis of (CICO)2, CICOCO’s infraredendssion at 1844 cm-1 was recorded by TRFTIR spectrometer.
文摘Time-resolved Fourier transform infrared emission spectroscopy is employed for studing gaseous reaction of CH3 with NO. The CH3 radical was produced by laser photolysis of CH3Br at 248 nm. The infrared emissions of vibrationally excited nascent products HCO (n3), HCN (n1, n3), NH2 (n3), secondary product HNO (n1) and possible product HNCO (n1) were observed. It verifies that the reaction channels of HCO + NH2 and HCN+H2O exist, and that one other channel HNCO + H may also occur.
基金Ⅴ. ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.20733005 and No.20673126), the National Basic Research Program of China (No.2007CB815200 and No.2007AA02Z116), and the Chinese Academy of Sciences.
文摘The environmentally important free radical reaction of chlorinated methyl CHCl2 with NO2 was investigated by step-scan time-resolved FTIR (TR-FTIR) emission spectroscopy. Vibrationally excited products of CHClO, NO, CO, and HCl are observed in the high-resolution IR emission spectra and three possible reaction channels are therefore elucidated. In particular, the product CO is newly detected and the product HCl is identified explicitly as a yield from the CHCl2+NO2 reaction, taking advantage of the sensitive detection of HCl and CO with TR-FTIR. These results are of particular interests to understand the related realistic chemical processes including atmospheric photochemistry, biofuel combustion, waste destruction, and smoking fire.
文摘The reaction of methylene radicals in their 3 B1 electronic ground state with molecular NO was studied. Pure CH2(X 3 B1 ) radicals were prodced by UV photolysis of ketene at 351 nm.The products were measured by Time-Resolved Fourier Transform Infrard (TR-FTIR) spectrometer. CO.OH .NH2 and HOCN or its isomer HNCO were found as primary prodcts and several possible channels of this reaction were suggested.
基金supported by the National Natural Science Foundation of China (20733005 &20973179)
文摘The 193 nm photodissociation dynamics of CH2CHCOC1 in the gas phase has been examined with the technique of time-resolved Fourier transform infrared emission (TR-FTIR) spectroscopy. Vibrationally excited photofragments of CO (v ≤ 5), HC1 (v ≤ 6), and C2H2 were observed and two photodissociation channels, the C-C1 fission channel and the HC1 elimina- tion channel have been identified. The vibrational and rotational state distributions of the photofragments CO and HC1 have been acquired by analyzing their fully rotationally resolved v→ v- 1 rovibrational progressions in the emission spectra, from which it has been firmly established that the mechanism involves production of HC1 via the four-center molecular elimination of CH2CHCOC1 after its internal conversion from the S1 state to the So state. In addition to the dominant C--C1 bond fission along the excited S1 state, the S1→S0 internal conversion has also been found to play an important role in the gas phase photolysis of CH2CHCOC1 as manifested by the considerable yield of HC1.
基金supported by the National Natural Science Foundation of China.
文摘The elementary reaction between allyl radical with oxygen molecule was experimentally investigated. The allyl radical was produced via laser photolysis of C3H5Br in gaseous phase. Nascent vibrational excited products HCO, CO2, CH3CHO and HCOOH were recorded by the time- resolved Fourier transform infrared spectroscopy. The product channels of C2H5+CO2, CH3CHO+HCO, and HCOOH + C2H3 have been identified. The vibrational populations of product CO2 are obtained by spectral simulation. A mechanism forming a series of three-membered ring-struc- ture intermediates is suggested.