IOM CNR, Laboratorio TASC, S.S. 14, km 163.5, I-34012 Trieste, Italy.
J Phys Condens Matter. 2012 Aug 15;24(32):325402, 1-5. doi: 10.1088/0953-8984/24/32/325402. Epub 2012 Jul 18.
We measured the low energy excitation spectrum of α'-NaV (2)O(5) across its charge ordering and crystallographic phase transition with resonant inelastic x-ray scattering (RIXS) at the V L(3) edge. Exploiting the polarization dependence of the RIXS signal and the high resolution of the data, we reveal the excitation across the insulating gap at 1 eV and identify the excitations from occupied 3d(xy) bonding orbitals to unoccupied bonding 3d(xy) and 3d(yz)/3d(xz) orbitals. Furthermore we observe a progressive change of the electronic structure of α'-NaV (2)O(5) induced by soft x-ray irradiation, with the appearance of features characteristic of sodium deficient Na(x)V (2)O(5) (x < 1).
我们利用 V L(3) 边缘的共振非弹性 X 射线散射 (RIXS)，测量了 α'-NaV(2)O(5) 在电荷有序和晶相转变过程中的低能激发谱。利用 RIXS 信号的偏振依赖性和数据的高分辨率，我们揭示了在 1 eV 处的绝缘隙激发，并确定了来自占据的 3d(xy) 成键轨道到未占据的成键 3d(xy) 和 3d(yz)/3d(xz) 轨道的激发。此外，我们观察到软 X 射线辐照诱导的 α'-NaV(2)O(5) 电子结构的渐进变化，出现了 Na(x)V(2)O(5)(x<1)的特征。
