In this paper the values of the crystalline-electric-field parameters Anm for R2Fel7 and R2Fe17H3 （R=Tb,Ho,Er） are evaluated by fitting calculations to the magnetization curves measured on the single crystal at seve...In this paper the values of the crystalline-electric-field parameters Anm for R2Fel7 and R2Fe17H3 （R=Tb,Ho,Er） are evaluated by fitting calculations to the magnetization curves measured on the single crystal at several temperatures. The fitted Anm for R2Fe17 are strikingly different from those for the corresponding R2Fe17H3. The energy gaps between the lowest four energy levels for Ho ions in Ho2Fe17 can be reproduced by using the fitted Anm and exchange field 2μBHex, which estimated from the fit of the temperature dependence of the spontaneous magnetization combined with inelastic neutron scattering experiment.展开更多
Theoretical study about the magnetic properties of conjugated organic molecules containing borepin with π current density was carried out. 1-（2,4,6-Trimethylphenyl）borepin moiety is the center and other different g...Theoretical study about the magnetic properties of conjugated organic molecules containing borepin with π current density was carried out. 1-（2,4,6-Trimethylphenyl）borepin moiety is the center and other different groups are situated on the both fl sides, which are named molecules 1--12 as theoretical model in order to establish the rela- tionship between aromaticity and geometry variation of borepin. The optimized molecular structures of molecules 1--12 are almost keeping planar and the C2--C3 bond length of borepin turns longer from molecule 1 to molecule 12 Different borepin-annulated ring could change the conjugated effect of π-electron between borepin and these bore- pin-annulated rings. Moreover, the molecule presents antiaromaticity, in other words, the molecule became unstable when the C2--C3 bond length of borepin extended more than ca. O. 1417 nm. But the fl position fragment and substi- tuent groups of borepin are not affected in this case, they are still steady. However, the central borepin ring current is counteracted by symmetrical overlap of it with affiliated borepin-annulated ring current. Hence, the central borepin ring breaking would be liable to occur. These molecules have higher vertical ionization potentials（VIPs） and lower vertical electron affinities（VEAs）, which suggests that these molecules could easily exist in anionic form.展开更多
基金Project supported by Department of Science and Technology of Jilin Province and the National Natural Science Foundation of China （Grant No 10304006）.
文摘In this paper the values of the crystalline-electric-field parameters Anm for R2Fel7 and R2Fe17H3 （R=Tb,Ho,Er） are evaluated by fitting calculations to the magnetization curves measured on the single crystal at several temperatures. The fitted Anm for R2Fe17 are strikingly different from those for the corresponding R2Fe17H3. The energy gaps between the lowest four energy levels for Ho ions in Ho2Fe17 can be reproduced by using the fitted Anm and exchange field 2μBHex, which estimated from the fit of the temperature dependence of the spontaneous magnetization combined with inelastic neutron scattering experiment.
基金Supported by the National Natural Science Foundation of China（Nos.21003057, 21173096） and the Specialized Research Fund for the Doctoral Program of Higher Education of China（No.20110061110018）.
文摘Theoretical study about the magnetic properties of conjugated organic molecules containing borepin with π current density was carried out. 1-（2,4,6-Trimethylphenyl）borepin moiety is the center and other different groups are situated on the both fl sides, which are named molecules 1--12 as theoretical model in order to establish the rela- tionship between aromaticity and geometry variation of borepin. The optimized molecular structures of molecules 1--12 are almost keeping planar and the C2--C3 bond length of borepin turns longer from molecule 1 to molecule 12 Different borepin-annulated ring could change the conjugated effect of π-electron between borepin and these bore- pin-annulated rings. Moreover, the molecule presents antiaromaticity, in other words, the molecule became unstable when the C2--C3 bond length of borepin extended more than ca. O. 1417 nm. But the fl position fragment and substi- tuent groups of borepin are not affected in this case, they are still steady. However, the central borepin ring current is counteracted by symmetrical overlap of it with affiliated borepin-annulated ring current. Hence, the central borepin ring breaking would be liable to occur. These molecules have higher vertical ionization potentials（VIPs） and lower vertical electron affinities（VEAs）, which suggests that these molecules could easily exist in anionic form.
