Electronic states of CF2Cl2 （dichlorodifluoromethane, Freon 12） have been studied using a new type of electron momentum spectrometer with a very high efficiency at an impact energy of 1200 eV plus binding energy. Th...Electronic states of CF2Cl2 （dichlorodifluoromethane, Freon 12） have been studied using a new type of electron momentum spectrometer with a very high efficiency at an impact energy of 1200 eV plus binding energy. The experimental electron momentum profiles are compared with the density functional theory （DFT） and Hartree-Fock （HF） calculations. The relationship between orbital assignments in different coordinate systems is discussed. A new method of difference analysis based on the new type of electron momentum spectrometer is used to clarify the ambiguities regarding the orbital ordering.展开更多
The CO_2 laser induced room temperature reactions of CH_3CF_2H or another protium-donor CH_3CHClCH_3 with chlorine-atom donors (Z--Cl) CFCl_2CF_2Cl, CF_3CCl_3, CFCl_3 or CF_2Cl_2, have been investigated. Some of these...The CO_2 laser induced room temperature reactions of CH_3CF_2H or another protium-donor CH_3CHClCH_3 with chlorine-atom donors (Z--Cl) CFCl_2CF_2Cl, CF_3CCl_3, CFCl_3 or CF_2Cl_2, have been investigated. Some of these reactions can yield two important monomers (CF_2=CH_2 and CF_2=CFCl) for fluoropolymers simultaneously. The yield dependence of these two alkenes on experi- mental conditions has been studied. A laser-initiated chain process is supported by identifica- tion of Z--H intermediates in these reactions.展开更多
基金Project supported by the National Natural Science Foundation of China （Grant Nos 19854002, 19774037 and 10274040） and the Research Fund for the Doctorate Program of Higher Education （Grant No 1999000327）.
文摘Electronic states of CF2Cl2 （dichlorodifluoromethane, Freon 12） have been studied using a new type of electron momentum spectrometer with a very high efficiency at an impact energy of 1200 eV plus binding energy. The experimental electron momentum profiles are compared with the density functional theory （DFT） and Hartree-Fock （HF） calculations. The relationship between orbital assignments in different coordinate systems is discussed. A new method of difference analysis based on the new type of electron momentum spectrometer is used to clarify the ambiguities regarding the orbital ordering.
基金Project supported by the National Natural Science Foundation of China.
文摘The CO_2 laser induced room temperature reactions of CH_3CF_2H or another protium-donor CH_3CHClCH_3 with chlorine-atom donors (Z--Cl) CFCl_2CF_2Cl, CF_3CCl_3, CFCl_3 or CF_2Cl_2, have been investigated. Some of these reactions can yield two important monomers (CF_2=CH_2 and CF_2=CFCl) for fluoropolymers simultaneously. The yield dependence of these two alkenes on experi- mental conditions has been studied. A laser-initiated chain process is supported by identifica- tion of Z--H intermediates in these reactions.
