With a 30 keV mini-separator at the accelerator laboratory of Fudan University,we have successfully obtained about 1 nA fullerene ion bea.m.Under the same conditions,we have also observed the fragment ions C_(n)^(+) (...With a 30 keV mini-separator at the accelerator laboratory of Fudan University,we have successfully obtained about 1 nA fullerene ion bea.m.Under the same conditions,we have also observed the fragment ions C_(n)^(+) (n=20-40).The C_(60)^(+) (C_(70)^(+)) beams will be used study collision between fullerene and electrons,atoms and photons.展开更多
Fullerenes （C60/C70） linked up to Ni-doped ZnS through the medium of an amphalic polymer polyvinyl pyrrolidone （PVP） to form a new kind of photocatalyst for hydrogen evolution from aqueous Na2S/Na2SO3 solution und...Fullerenes （C60/C70） linked up to Ni-doped ZnS through the medium of an amphalic polymer polyvinyl pyrrolidone （PVP） to form a new kind of photocatalyst for hydrogen evolution from aqueous Na2S/Na2SO3 solution under visible light irradiation, the photocatalytic activities of this novel photocatalyst C60/C70-PVP- Zn0.999Ni0.001S are 3-5 fold higher compared with that of precurse catalyst Zn0.999Ni0.001S. This result could be attributed to Schottky barrier layer built between C60/C70 and Zn0.999Ni0.001S due to the electro-negativity of C60 and characteristic of being used as a multiple electron acceptor. C60 or C60/C70 its moiety, with its low energy first excited singlet state, is a good energy acceptor and in addition readily accepts multiple electrons, making it a potential electron accumulate as we know, which could protect the separation between electrons and holes against combination. This is an important reason for the marked increase of amount of H2 evolution during the photocatalytic process for the composite system C60/C70-PVP- Zn0.999Ni0.001S.展开更多
With many special physical and chemical characteristics, the fullerenes in cage-likestructure (C<sub>60</sub>, C<sub>70</sub>,etc.)have become a subject in the front fields of material science....With many special physical and chemical characteristics, the fullerenes in cage-likestructure (C<sub>60</sub>, C<sub>70</sub>,etc.)have become a subject in the front fields of material science.According to Ref.[1], the C<sub>60</sub>and C<sub>70</sub> molecules may be in two kinds of crystal struc-tures at room temperature. When deposited on a gold （Au） film, the molecules arein fcc structure(α=1.428×10<sup>-9</sup>m), and when deposited on a glass surface, themolecules are in hcp structure (α=1.005×10<sup>-9</sup>m, c=1.641×10<sup>-9</sup>m). The phase transi-tions have been observed at different temperatures. Moreover, the C<sub>60</sub>/C<sub>70</sub>展开更多
In search of new systems with a photoexcited redox pair which exhibits a strong and stable photoinduced absorption band to understand the photophyscial and photochemical properties of electron transfer between fullere...In search of new systems with a photoexcited redox pair which exhibits a strong and stable photoinduced absorption band to understand the photophyscial and photochemical properties of electron transfer between fullerenes (C 60/C 70) and organic donor [N,N,N′,N′-tetra(p-methylphenyl)-4,4′-diamino-1,1′-diphenyl sulphide (TPDAS)], we studied characteristic absorption spectra in the near-IR region obtained from 532 nm nanosecond laser flash photolysis of a mixture of the fullerenes (C 60/C 70) and TPDAS in polar solvents. When fullerenes (C 60/C 70) were photoexcited, the rise of the radical anion of fullerenes (C 60/C 70) with the rapid decay of their excited triplet states were observed in benzonitrile. It can be deduced that the electron transfer reaction does take place from TPDAS to excited triplet state of fullerenes (C 60/C 70). The rate constants (k et) and quantum yields (Φ et) of this process have been also evaluated.展开更多
Since Kroto discovered the C<sub>60</sub> molecules in 1985, much theoretical and experi-mental work has been done to study the physical and chemical properties of carbonclusters. A carbon cluster C<sub...Since Kroto discovered the C<sub>60</sub> molecules in 1985, much theoretical and experi-mental work has been done to study the physical and chemical properties of carbonclusters. A carbon cluster C<sub>N</sub> is like a three-connected polyhedral cage with N atoms（N is even number）, arranged in 12 pentagonal and N/2-10 hexagonal rings. In thecluster, each carbon contributes three orbitals and three electrons to the σ-bonds net-work and gives one π orbital and one electron to the big conjugated π-bond system.展开更多
We have theoretically investigated the one- and two-photon absorption properties of C60 and C70 using the ZINDO method. From the results it is suggested that the one-photon absorption spectra are in agreement with the...We have theoretically investigated the one- and two-photon absorption properties of C60 and C70 using the ZINDO method. From the results it is suggested that the one-photon absorption spectra are in agreement with the experimental observations. It is found that the maximum TPA cross section of C70 is more than twice that of C60, which is consistent with the experimental results. A notable point is that the TPA process of C60 is different from that of C70 as well as other ordinary conjugated molecules.展开更多
Based on the hybrid orbital theory of Pauling, Haddon developed the π-orbital axis vector （POAV） analysis for treating the hybridization and the orientation of π orbitals in nonplanar conjugated organic systems. H...Based on the hybrid orbital theory of Pauling, Haddon developed the π-orbital axis vector （POAV） analysis for treating the hybridization and the orientation of π orbitals in nonplanar conjugated organic systems. He programmed the calculation, giving numerical results for fullerenes. Recently, Chen Qiong et al. also constructed hybrid orbitals of C<sub>60</sub> and C<sub>70</sub>, but the assumed orientation of π-hybrid orbitals seems to be not quite realistic. In this note, we made an analysis on POAV, construct the hybrid orbitals and determine the orientation of π-hybrid orbitals in C<sub>60</sub> and C<sub>70</sub> in analytical and numerical forms, respectively.展开更多
文摘With a 30 keV mini-separator at the accelerator laboratory of Fudan University,we have successfully obtained about 1 nA fullerene ion bea.m.Under the same conditions,we have also observed the fragment ions C_(n)^(+) (n=20-40).The C_(60)^(+) (C_(70)^(+)) beams will be used study collision between fullerene and electrons,atoms and photons.
基金Key Project of Chinese Ministry of Education （No. 105105）, Program for New Century Excellent Talents in University of Chinese Ministry of Education （No. NCET-04-0643）, and the Taishan Mountain Scholar Construction Engineering Special Fund of Shandong Province, China.
文摘Fullerenes （C60/C70） linked up to Ni-doped ZnS through the medium of an amphalic polymer polyvinyl pyrrolidone （PVP） to form a new kind of photocatalyst for hydrogen evolution from aqueous Na2S/Na2SO3 solution under visible light irradiation, the photocatalytic activities of this novel photocatalyst C60/C70-PVP- Zn0.999Ni0.001S are 3-5 fold higher compared with that of precurse catalyst Zn0.999Ni0.001S. This result could be attributed to Schottky barrier layer built between C60/C70 and Zn0.999Ni0.001S due to the electro-negativity of C60 and characteristic of being used as a multiple electron acceptor. C60 or C60/C70 its moiety, with its low energy first excited singlet state, is a good energy acceptor and in addition readily accepts multiple electrons, making it a potential electron accumulate as we know, which could protect the separation between electrons and holes against combination. This is an important reason for the marked increase of amount of H2 evolution during the photocatalytic process for the composite system C60/C70-PVP- Zn0.999Ni0.001S.
文摘With many special physical and chemical characteristics, the fullerenes in cage-likestructure (C<sub>60</sub>, C<sub>70</sub>,etc.)have become a subject in the front fields of material science.According to Ref.[1], the C<sub>60</sub>and C<sub>70</sub> molecules may be in two kinds of crystal struc-tures at room temperature. When deposited on a gold （Au） film, the molecules arein fcc structure(α=1.428×10<sup>-9</sup>m), and when deposited on a glass surface, themolecules are in hcp structure (α=1.005×10<sup>-9</sup>m, c=1.641×10<sup>-9</sup>m). The phase transi-tions have been observed at different temperatures. Moreover, the C<sub>60</sub>/C<sub>70</sub>
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 0 0 710 12 ) ,ResearchFundfortheYoungTeacherPro gramofHigherEducationofChina (No .2 0 0 0 6 5 )andtheNaturalScienceFoundationofGuangdongProvince (No .0 0 0 70 0 )
文摘In search of new systems with a photoexcited redox pair which exhibits a strong and stable photoinduced absorption band to understand the photophyscial and photochemical properties of electron transfer between fullerenes (C 60/C 70) and organic donor [N,N,N′,N′-tetra(p-methylphenyl)-4,4′-diamino-1,1′-diphenyl sulphide (TPDAS)], we studied characteristic absorption spectra in the near-IR region obtained from 532 nm nanosecond laser flash photolysis of a mixture of the fullerenes (C 60/C 70) and TPDAS in polar solvents. When fullerenes (C 60/C 70) were photoexcited, the rise of the radical anion of fullerenes (C 60/C 70) with the rapid decay of their excited triplet states were observed in benzonitrile. It can be deduced that the electron transfer reaction does take place from TPDAS to excited triplet state of fullerenes (C 60/C 70). The rate constants (k et) and quantum yields (Φ et) of this process have been also evaluated.
文摘Since Kroto discovered the C<sub>60</sub> molecules in 1985, much theoretical and experi-mental work has been done to study the physical and chemical properties of carbonclusters. A carbon cluster C<sub>N</sub> is like a three-connected polyhedral cage with N atoms（N is even number）, arranged in 12 pentagonal and N/2-10 hexagonal rings. In thecluster, each carbon contributes three orbitals and three electrons to the σ-bonds net-work and gives one π orbital and one electron to the big conjugated π-bond system.
基金Project supported by the National Natural Science Foundation of China (Nos. 20273023 90101026) and the Key Laboratory for Supramolecular Structure and Material of Jilin University.
文摘We have theoretically investigated the one- and two-photon absorption properties of C60 and C70 using the ZINDO method. From the results it is suggested that the one-photon absorption spectra are in agreement with the experimental observations. It is found that the maximum TPA cross section of C70 is more than twice that of C60, which is consistent with the experimental results. A notable point is that the TPA process of C60 is different from that of C70 as well as other ordinary conjugated molecules.
基金Project supported by the National Natural Science Foundation of China
文摘Based on the hybrid orbital theory of Pauling, Haddon developed the π-orbital axis vector （POAV） analysis for treating the hybridization and the orientation of π orbitals in nonplanar conjugated organic systems. He programmed the calculation, giving numerical results for fullerenes. Recently, Chen Qiong et al. also constructed hybrid orbitals of C<sub>60</sub> and C<sub>70</sub>, but the assumed orientation of π-hybrid orbitals seems to be not quite realistic. In this note, we made an analysis on POAV, construct the hybrid orbitals and determine the orientation of π-hybrid orbitals in C<sub>60</sub> and C<sub>70</sub> in analytical and numerical forms, respectively.
