J JIMÉNEZ-MIER,1,* P OLALDE-VELASCO,2
P DE LA MORA,3
W-L YANG,4
AND J DENLINGER4
1 Instituto de Ciencias Nucleares, UNAM, 04510 Ciudad de México, México
2 Instituto de Física, Benemérita Universidad Autónoma de Puebla, Puebla, A. Postal J-48 Puebla, Puebla 72750, Mexico
3 Facultad de Ciencias, UNAM, 04510 Ciudad de México, México
4 The Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, CA 94720, USA
*Email: jimenez@nucleares.unam.mx
Abstract Resonant inelastic x-ray scattering (RIXS) is used to study the electronic structure of NiF2 , which is the most ionic of the nickel compounds. RIXS can be viewed as a coherent two-steps process involving the absorption and the emission of x-rays. The soft x-ray absorption spectrum (XAS) at the metal L2,3 edge indicate the importance of atomic multiplet effects. RIXS spectra at L2,3 contain clearly defined emission peaks corresponding to d-excited states of Ni2+ at energies few eV below the elastic emission, which is strongly suppressed. These results are confirmed by atomic multiplet calculations using the Kramers-Heisenberg formula for RIXS processes. For larger energy losses, the emission spectra have a broad charge-transfer peak that results from the decay of hybridized Ni(3d)-F(2p) valence states. This is confirmed by comparison of the absorption and emission spectra recorded at the nickel L and fluorine K edges with F p and Ni d partial density of states using LDA + U calculations. Keywords: Core-level spectroscopies. RIXS, Nickel difluoride, Electronic structure
To read full paper please click here;
http://dspace.chitkara.edu.in/jspui/bitstream/1/861/1/51001_JNP_JIMENEZ.pdf
1 Instituto de Ciencias Nucleares, UNAM, 04510 Ciudad de México, México
2 Instituto de Física, Benemérita Universidad Autónoma de Puebla, Puebla, A. Postal J-48 Puebla, Puebla 72750, Mexico
3 Facultad de Ciencias, UNAM, 04510 Ciudad de México, México
4 The Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, CA 94720, USA
*Email: jimenez@nucleares.unam.mx
Abstract Resonant inelastic x-ray scattering (RIXS) is used to study the electronic structure of NiF2 , which is the most ionic of the nickel compounds. RIXS can be viewed as a coherent two-steps process involving the absorption and the emission of x-rays. The soft x-ray absorption spectrum (XAS) at the metal L2,3 edge indicate the importance of atomic multiplet effects. RIXS spectra at L2,3 contain clearly defined emission peaks corresponding to d-excited states of Ni2+ at energies few eV below the elastic emission, which is strongly suppressed. These results are confirmed by atomic multiplet calculations using the Kramers-Heisenberg formula for RIXS processes. For larger energy losses, the emission spectra have a broad charge-transfer peak that results from the decay of hybridized Ni(3d)-F(2p) valence states. This is confirmed by comparison of the absorption and emission spectra recorded at the nickel L and fluorine K edges with F p and Ni d partial density of states using LDA + U calculations. Keywords: Core-level spectroscopies. RIXS, Nickel difluoride, Electronic structure
To read full paper please click here;
http://dspace.chitkara.edu.in/jspui/bitstream/1/861/1/51001_JNP_JIMENEZ.pdf