  The Zhang-Rice (ZR) state is a strongly hybridized bound state formed by the
transition metal and oxygen atoms. The spin-fluctuations within the ZR state
are known to play an important role in high-$T_\mathrm{c}$ superconductivity in
cuprates. Here, we employ a combination of angle-resolved photoemission
spectroscopy (ARPES), X-ray photoemission spectroscopy (XPS), and {\it ab
initio} embedded dynamical mean-field theory (eDMFT) to investigate the
influence of magnetic ordering on the spectral characteristics of the valence
band and Mn 2$p$ core-level in MnO (001) ultrathin films. Our results
demonstrate that a complex spin-selective evolution of Mn 3$d$$-$O 2$p$
hybridization develops due to the long-range antiferromagnetic (AFM) ordering.
This hybridization significantly alters the spectral shape and weight of the ZR
state. Specifically, in the AFM phase, we observed the sharpening of the ZR
state and band folding with the periodicity of the AFM unit cell of MnO(001).
We also demonstrated a strong connection between the spectral evolution of the
ZR state and the non-local screening channels of the photoexcited core holes.
Further, our detailed temperature-dependent study reveals the presence of
short-range antiferromagnetic correlations that exist at much higher
temperatures than $T_\mathrm{N}$. Such comprehensive studies showing the
evolution of the ZR state across the magnetic transitions and its implication
to the core-hole screening have never been reported in any 3$d$ binary
transition metal oxides.
