The geometries of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2 radicals were investigated by density functional theory(DFT) method. The calculated results indicate that all the three radicals have pyramidal shapes at their cen...The geometries of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2 radicals were investigated by density functional theory(DFT) method. The calculated results indicate that all the three radicals have pyramidal shapes at their centers, and the aC is one top of the pyramids. Based on the DFT optimized geometries, the hyperfine coupling constants(hfec's) of the 19F atoms of the three radicals were calculated by B3LYP, MP2(full) and QCISD(full) methods. The calculated values agree with the experimental values, especially for the a values of Fa, the a values are 125.6× 10 -4, 104.2× 10 - 4, and 83.2×10 -4 T of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2, respectively. These results better explain the experimental observation.展开更多
基金Supported by the Major State Basic Research Development Programs of China(No2007CB815206)the National Natural Science Foundation of China(Nos20873010, 20720102038)the Fundamental Research Funds for the Central Universities of China
文摘The geometries of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2 radicals were investigated by density functional theory(DFT) method. The calculated results indicate that all the three radicals have pyramidal shapes at their centers, and the aC is one top of the pyramids. Based on the DFT optimized geometries, the hyperfine coupling constants(hfec's) of the 19F atoms of the three radicals were calculated by B3LYP, MP2(full) and QCISD(full) methods. The calculated values agree with the experimental values, especially for the a values of Fa, the a values are 125.6× 10 -4, 104.2× 10 - 4, and 83.2×10 -4 T of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2, respectively. These results better explain the experimental observation.