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
Paramagnetic endohedral metallofullerenes with well protected unpaired spin have potential applications in molecular-scale qubit processing and magnetoreception system. In this study, a paramagnetic metallofullerene S...Paramagnetic endohedral metallofullerenes with well protected unpaired spin have potential applications in molecular-scale qubit processing and magnetoreception system. In this study, a paramagnetic metallofullerene Sc_(3)C_(2)@C_(80) dimer with covalently bonded two spin centers was synthesized. Electron paramagnetic resonance (EPR) results further revealed the varied spin-nuclei couplings and paramagnetic property for Sc_(3)C_(2)@C_(80) dimer. Briefly, the Sc_(3)C_(2)@C_(80) dimer in toluene solution shows EPR hyperfine splittings originating from the spin-Sc couplings. However, the Sc_(3)C_(2)@C_(80) dimer in solid state shows the disappearance of hyperfine structure and a single EPR signal caused by its two-spin-center structure. The transformation of EPR signals can be further finely modulated by controlling the dynamic motion of Sc_(3)C_(2)@C80 dimer in chloronaphthalene. The Sc_(3)C_(2)@C_(80) dimer with two spin centers possesses varied paramagnetic properties, demonstrating its potential as new magnetic material.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.
基金This work was supported by the National Natural Science Foundation of China(Nos.52022098,51672281,51972309,and 51832008)T.Wang particularly thanks the Youth Innovation Promotion Association of CAS(Y201910).
文摘Paramagnetic endohedral metallofullerenes with well protected unpaired spin have potential applications in molecular-scale qubit processing and magnetoreception system. In this study, a paramagnetic metallofullerene Sc_(3)C_(2)@C_(80) dimer with covalently bonded two spin centers was synthesized. Electron paramagnetic resonance (EPR) results further revealed the varied spin-nuclei couplings and paramagnetic property for Sc_(3)C_(2)@C_(80) dimer. Briefly, the Sc_(3)C_(2)@C_(80) dimer in toluene solution shows EPR hyperfine splittings originating from the spin-Sc couplings. However, the Sc_(3)C_(2)@C_(80) dimer in solid state shows the disappearance of hyperfine structure and a single EPR signal caused by its two-spin-center structure. The transformation of EPR signals can be further finely modulated by controlling the dynamic motion of Sc_(3)C_(2)@C80 dimer in chloronaphthalene. The Sc_(3)C_(2)@C_(80) dimer with two spin centers possesses varied paramagnetic properties, demonstrating its potential as new magnetic material.
