| Autor: |
KUIPER, P, VANELP, J, SAWATZKY, GA, FUJIMORI, A, HOSOYA, S, DELEEUW, DM |
| Jazyk: |
angličtina |
| Rok vydání: |
1991 |
| Předmět: |
|
| Zdroj: |
Physical Review. B: Condensed Matter and Materials Physics, 44(9), 4570-4575. AMER PHYSICAL SOC |
| ISSN: |
1098-0121 |
| Popis: |
Oxygen 1s x-ray-absorption measurements of La(2-x)SrxNiO4+delta (0 less-than-or-equal-to x less-than-or-equal-to 1.15) are presented, together with O 1s polarization-dependent x-ray absorption on single-crystal La1.85Sr0.15NiO4. It is concluded that the charge-compensating holes have mainly oxygen 2p character. The Ni 3d9 final states reached because of the p-d hybridization in the ground state are strongly polarized in the (a,b) plane. The Sr-induced O 2p holes are found to be distributed equally over in-plane p(x),p(y) and out-of-plane p(z) orbitals. Possible explanations for this are presented. The intrinsic band gap of La2NiO4 is found to be at least 4 eV. The bremsstrahlung-isochromat-spectroscopy results show that the Sr-induced states are spread out over a large portion of the band gap and are not concentrated at the top of the valence band. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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