Ultra-violet photoemission spectroscopy measurements for CO adsorption on the(2×2)-Cs precovered Ru(0001)surface were performed.The Cs 5p(5p3/2)level(Cs state)locates at 11.3 eV in binding energy for the(2×2...Ultra-violet photoemission spectroscopy measurements for CO adsorption on the(2×2)-Cs precovered Ru(0001)surface were performed.The Cs 5p(5p3/2)level(Cs state)locates at 11.3 eV in binding energy for the(2×2)-Cs overlayer on Ru(0001).Upon the CO adsorption,a new peak,which is associated with the Cs 5p state for the Cs adatoms influenced by the neighbouring CO adsorbed(the Cs+CO state),appears at the lower binding energy side of the Cs state.This new peak is at 10.8,eV for the CO saturation where the(2×2)-Cs+2CO compound layer is formed.This result gives clear evidence for local interaction of Cs and CO on the Ru(0001)surface.展开更多
By using a newly implemented high-resolution electron energy loss spectrometer with better resolution,a new loss at a energy near to double energy of the Cs-Ru stretching vibration,and its dependence on Cs coverage fo...By using a newly implemented high-resolution electron energy loss spectrometer with better resolution,a new loss at a energy near to double energy of the Cs-Ru stretching vibration,and its dependence on Cs coverage for Cs overlayer on Ru(0001)were observed.Since the energy is slightly smaller than the double energy of the Cs-Ru vibration(intrinsic loss),overtone excitation must be responsible for this new loss observed,but two-phonon process is not excluded.展开更多
Vibrational analysis of oxygen adsorption on the Cs and CO coadsorbate precovered Ru(0001)surface was carried out by means of high-resolution electron energy loss spectroscopy.For submonolayer Cs coverages on Ru(0001)...Vibrational analysis of oxygen adsorption on the Cs and CO coadsorbate precovered Ru(0001)surface was carried out by means of high-resolution electron energy loss spectroscopy.For submonolayer Cs coverages on Ru(0001)j an appropriate amount of CO adsorption leads to formation of(2x2)-Cs+2CO islands.Subsequent oxygen adsorption on this Cs and CO coadsorbate precovered surface results in a remarkable change of high-resolution electron energy loss spectroscopy.The loss peak of C-O stretch mode for 2x2 island species decreases in intensity,which is accompanied by appearance of new bands at about 87 and 240 meV.The results show that Cs adatoms and CO molecules are rearranged upon oxygen adsorption,and are correlated with coexistence of bare surface CO and a mixed phase of Cs,CO,and O.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos.19774047 and 19874053the National Hi-Tech Inertial Confinement Fusion Committee.
文摘Ultra-violet photoemission spectroscopy measurements for CO adsorption on the(2×2)-Cs precovered Ru(0001)surface were performed.The Cs 5p(5p3/2)level(Cs state)locates at 11.3 eV in binding energy for the(2×2)-Cs overlayer on Ru(0001).Upon the CO adsorption,a new peak,which is associated with the Cs 5p state for the Cs adatoms influenced by the neighbouring CO adsorbed(the Cs+CO state),appears at the lower binding energy side of the Cs state.This new peak is at 10.8,eV for the CO saturation where the(2×2)-Cs+2CO compound layer is formed.This result gives clear evidence for local interaction of Cs and CO on the Ru(0001)surface.
基金Supported in part by the National Natural Science Foundation of China under Grant No.19774047.
文摘By using a newly implemented high-resolution electron energy loss spectrometer with better resolution,a new loss at a energy near to double energy of the Cs-Ru stretching vibration,and its dependence on Cs coverage for Cs overlayer on Ru(0001)were observed.Since the energy is slightly smaller than the double energy of the Cs-Ru vibration(intrinsic loss),overtone excitation must be responsible for this new loss observed,but two-phonon process is not excluded.
基金Supported in part by the National Natural Science Foundation of China under Grand No.19774047.
文摘Vibrational analysis of oxygen adsorption on the Cs and CO coadsorbate precovered Ru(0001)surface was carried out by means of high-resolution electron energy loss spectroscopy.For submonolayer Cs coverages on Ru(0001)j an appropriate amount of CO adsorption leads to formation of(2x2)-Cs+2CO islands.Subsequent oxygen adsorption on this Cs and CO coadsorbate precovered surface results in a remarkable change of high-resolution electron energy loss spectroscopy.The loss peak of C-O stretch mode for 2x2 island species decreases in intensity,which is accompanied by appearance of new bands at about 87 and 240 meV.The results show that Cs adatoms and CO molecules are rearranged upon oxygen adsorption,and are correlated with coexistence of bare surface CO and a mixed phase of Cs,CO,and O.
