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arXiv · 2006.04341

Charge correlation in V$_2$OPO$_4$ probed by hard x-ray photoemission spectroscopy

K. Murota·E. Pachoud·J. P. Attfield·R. Glaum·T. Yasuda·D. Ootsuki·Y. Takagi·A. Yasui·D. I. Khomskii·T. Mizokawa
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Abstract

Electronic properties of V$_2$OPO$_4$ have been investigated by means of hard x-ray photoemission spectroscopy (HAXPES) and subsequent theoretical calculations. The V 1$s$ and 2$p$ HAXPES spectra are consistent with the charge ordering of V$^{2+}$ and V$^{3+}$. The binding energy difference between the V$^{2+}$ and V$^{3+}$ components is unexpectedly large indicating large bonding-antibonding splitting between them in the final states of core level photoemission. The V 1$s$ HAXPES spectrum exhibits a charge transfer satellite which can be analyzed by configuration interaction calculations on a V$_2$O$_9$ cluster. The V 3$d$ spectral weight near the Fermi level is assigned to the 3$d$ $t_{2g}$ orbitals of the V$^{2+}$ site. The broad V 3$d$ spectral distribution is consistent with the strong hybridization between V$^{2+}$ and V$^{3+}$ in the ground state. The core level and valence band HAXPES results indicate substantial charge transfer from the V$^{2+}$ site to the V$^{3+}$ site.7 figure

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K. Murota, E. Pachoud, J. P. Attfield, R. Glaum, T. Yasuda, D. Ootsuki, Y. Takagi, A. Yasui, D. I. Khomskii, T. Mizokawa. 2020-06-08. Charge correlation in V$_2$OPO$_4$ probed by hard x-ray photoemission spectroscopy. https://doi.org/10.1103/physrevb.101.235159

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