A model incorporating(Cs-A-ABAB)stacking with Cs atoms chemisorbed in hollow sites 2.70A above the top graphite plane and the two top graphite layers shear-shifted to AA stacking and expanded to a separation of 3.85A ...A model incorporating(Cs-A-ABAB)stacking with Cs atoms chemisorbed in hollow sites 2.70A above the top graphite plane and the two top graphite layers shear-shifted to AA stacking and expanded to a separation of 3.85A is the most reliable structure for Cs/graphite(0001)-(√3×√3)surfaces.The coexisting diffraction pattern including the diffraction ring and another set of (√3×√3) diffraction pattern which has a 30°rotation angle with respect to the normal(√3×√3)R3O°diffraction pattern could be explained.We consider this strueture to be in a prein ter cal ation state.展开更多
Work function and photoemission spectroscopy have been applied to the study of the interaction of Co overlayers with the ion sputtered basal face of MoS_(2)(0001).The experimental results show that upon Co deposition ...Work function and photoemission spectroscopy have been applied to the study of the interaction of Co overlayers with the ion sputtered basal face of MoS_(2)(0001).The experimental results show that upon Co deposition the work function of the MoS_(2)substrate drops rapidly and reaches a minimum value of-0.65eV forΔФ,and then increases to the metal Co work function at coverages greater than a monolayer.The Fermi level pinning at 2.2eV above the Mo 4dz2 peak has been found at a low submonolayer coverage.展开更多
The two-dimensional autocorrelation function of island separations for commensurately adsorbed overlayers is evaluated and used to calculate the angular profiles of the diffracted beams from arbitrary distribution of ...The two-dimensional autocorrelation function of island separations for commensurately adsorbed overlayers is evaluated and used to calculate the angular profiles of the diffracted beams from arbitrary distribution of overlayer islands.Model calculations are made for a realistic surface.The results are compared to the low energy electron diffraction(LEED)measurement of O/W(112)system and quantitative structural information on the distribution of islands for overlayers is then extracted.展开更多
The orientational ordering in adsorbed incommensurate monolayers is discussed in an anharmonic approach.A nonlinear relationship is predicted between the orientation of the monolayer relative to the substrate and the ...The orientational ordering in adsorbed incommensurate monolayers is discussed in an anharmonic approach.A nonlinear relationship is predicted between the orientation of the monolayer relative to the substrate and the monolayer lattice parameter.Calculated values of the rninimum energy crientation angle for Ar on graphite are in good agreement with the experimental reported measurements.展开更多
By introducing mass density waves,we have determined the positions and intensities of a quartet of spots around the(±1/2,±1/2)positions on a clean Mo(100)surface at low temperature.lt is shown that the Mo(10...By introducing mass density waves,we have determined the positions and intensities of a quartet of spots around the(±1/2,±1/2)positions on a clean Mo(100)surface at low temperature.lt is shown that the Mo(100)-C(2x2)*incomensurate surface structure is a stable one and can be described in terms of a C(2x2)superlattice modulated by square-like-domains.The domain size and the direction of the domain structure relative to Mo(100)lattice are also discussed.展开更多
The double peak structure of O_(18) in photoemission spectra of Bi-Sr-Ca-Cu-O superconductor is studied by XPS,and compared with that of SrCO_(3).The result indicates that the double peak structure of O_(18) spectra i...The double peak structure of O_(18) in photoemission spectra of Bi-Sr-Ca-Cu-O superconductor is studied by XPS,and compared with that of SrCO_(3).The result indicates that the double peak structure of O_(18) spectra is closely related with the Sr_(3d) and C_(1s) spectra,and arises primarily from the SrCO_(3)-like complex caused by the contamination of CO_(2) in air.展开更多
基金Project suported by the National Natural Science Foundation of China.
文摘A model incorporating(Cs-A-ABAB)stacking with Cs atoms chemisorbed in hollow sites 2.70A above the top graphite plane and the two top graphite layers shear-shifted to AA stacking and expanded to a separation of 3.85A is the most reliable structure for Cs/graphite(0001)-(√3×√3)surfaces.The coexisting diffraction pattern including the diffraction ring and another set of (√3×√3) diffraction pattern which has a 30°rotation angle with respect to the normal(√3×√3)R3O°diffraction pattern could be explained.We consider this strueture to be in a prein ter cal ation state.
文摘Work function and photoemission spectroscopy have been applied to the study of the interaction of Co overlayers with the ion sputtered basal face of MoS_(2)(0001).The experimental results show that upon Co deposition the work function of the MoS_(2)substrate drops rapidly and reaches a minimum value of-0.65eV forΔФ,and then increases to the metal Co work function at coverages greater than a monolayer.The Fermi level pinning at 2.2eV above the Mo 4dz2 peak has been found at a low submonolayer coverage.
基金supported by the Science Fund of the Chinese Academy of Sciences。
文摘The two-dimensional autocorrelation function of island separations for commensurately adsorbed overlayers is evaluated and used to calculate the angular profiles of the diffracted beams from arbitrary distribution of overlayer islands.Model calculations are made for a realistic surface.The results are compared to the low energy electron diffraction(LEED)measurement of O/W(112)system and quantitative structural information on the distribution of islands for overlayers is then extracted.
基金the Science Fund of the Chinese Academy of Sciences。
文摘The orientational ordering in adsorbed incommensurate monolayers is discussed in an anharmonic approach.A nonlinear relationship is predicted between the orientation of the monolayer relative to the substrate and the monolayer lattice parameter.Calculated values of the rninimum energy crientation angle for Ar on graphite are in good agreement with the experimental reported measurements.
基金This work was supported by the Science Fund of the Chinese Academy of Sciences.
文摘By introducing mass density waves,we have determined the positions and intensities of a quartet of spots around the(±1/2,±1/2)positions on a clean Mo(100)surface at low temperature.lt is shown that the Mo(100)-C(2x2)*incomensurate surface structure is a stable one and can be described in terms of a C(2x2)superlattice modulated by square-like-domains.The domain size and the direction of the domain structure relative to Mo(100)lattice are also discussed.
基金supported by The National Center for Research and Development on Superconductivity.
文摘The double peak structure of O_(18) in photoemission spectra of Bi-Sr-Ca-Cu-O superconductor is studied by XPS,and compared with that of SrCO_(3).The result indicates that the double peak structure of O_(18) spectra is closely related with the Sr_(3d) and C_(1s) spectra,and arises primarily from the SrCO_(3)-like complex caused by the contamination of CO_(2) in air.
