Oxygen K-edge XANES investigation of NicMg(1-c)O solid solutions.
A series of Ni(c)Mg(1-c)O solid solutions are characterized by means of synchrotron radiation X-ray diffraction and X-ray absorption near-edge-structure spectroscopy at oxygen K-edge (532 eV). A dramatic drop of the pre-edge peak intensity is observed in the Ni(c)Mg(1-c)O system upon dilution. It can be attributed to a decrease of 3d(8)(Ni(2+))-2p(O(2-)) mixing upon dilution with magnesium ions due to a decrease of the number of 3d vacancies as nickel ion is replaced by magnesium ion. Similarly, the decrease of the number of 4s and 4p vacancies also leads to a decrease of 4s4p(Ni(2+))-2p(O(2-)) hybridization, and hence a drop of intensities of features B and C. The features E and F are more sensitive to the increase of the degree of disorder upon dilution than feature D, revealing that the latter is mainly dependent by the medium-range order.
Chen
Dongliang
D
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
Zhong
Jun
J
Wu
Xiang
X
Wu
Ziyu
Z
Mironova-Ulmane
Nina
N
Kuzmin
Alexei
A
Marcelli
Augosto
A
D008274:Magnesium / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry; D012996:Solutions; D013057:Spectrum Analysis / Q000379:methods*; D014961:X-Ray Diffraction
D012996:Solutions; D012965:Sodium Chloride; D009532:Nickel; D008274:Magnesium; D010100:Oxygen