High-energy Ce-3d photoemission: Bulk properties of CeM{sub 2} (M=Fe,Co,Ni) and Ce{sub 7}Ni{sub 3}
High-energy Ce-3d photoemission: Bulk properties of CeM{sub 2} (M=Fe,Co,Ni) and Ce{sub 7}Ni{sub 3}
复制标题
高能Ce-3d光电子发射：CeM{sub 2} (M=Fe,Co,Ni) 和Ce{sub 7}Ni{sub 3}的体特性
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
G. Olcese
中科院分区：
文献类型：
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作者：
L. Braicovich;N. Brookes;C. Dallera;M. Salvietti;G. Olcese
We study the photon energy dependence of Ce-3d photoemission in CeM{sub 2} compounds (M=Fe,Co,Ni) and in Ce{sub 7}Ni{sub 3} with measurements taken with synchrotron radiation in the photon energy range 1050{endash}3850 eV. The results show a drastic increase of the bulk sensitivity at the higher energies due to the increase of the photoelectron escape depth. The spectra at 3850 eV are largely dominated by the bulk contribution, which is typically 85{percent} of the total intensity in the CeM{sub 2} compounds. The results allow us to obtain the bulk contribution to the spectra in CeM{sub 2} with a procedure presented here and giving the fractional weights of the bulk f{sup 0}, f{sup 1}, and f{sup 2} configurations. In the CeM{sub 2} compounds a correlation is found between these spectral weights and the crystallographic data showing that the hybridization is nonmonotonic versus the atomic number of the transition metal. We discuss the results both in connection with an impurity model and with the available calculations in an itinerant model. Moreover, the results suggest that the bulk hybridization in CeM{sub 2} systems with heavy transition metals has been probably underestimated up to now. {copyright} {ital 1997} {ital The American Physical Society}
We study the photon energy dependence of Ce-3d photoemission in CeM{sub 2} compounds (M=Fe,Co,Ni) and in Ce{sub 7}Ni{sub 3} with measurements taken with synchrotron radiation in the photon energy range 1050{endash}3850 eV. The results show a drastic increase of the bulk sensitivity at the higher energies due to the increase of the photoelectron escape depth. The spectra at 3850 eV are largely dominated by the bulk contribution, which is typically 85{percent} of the total intensity in the CeM{sub 2} compounds. The results allow us to obtain the bulk contribution to the spectra in CeM{sub 2} with a procedure presented here and giving the fractional weights of the bulk f{sup 0}, f{sup 1}, and f{sup 2} configurations. In the CeM{sub 2} compounds a correlation is found between these spectral weights and the crystallographic data showing that the hybridization is nonmonotonic versus the atomic number of the transition metal. We discuss the results both in connection with an impurity model and with the available calculations in an itinerant model. Moreover, the results suggest that the bulk hybridization in CeM{sub 2} systems with heavy transition metals has been probably underestimated up to now. {copyright} {ital 1997} {ital The American Physical Society}