Exchange interactions and sensitivity of the Ni two-hole spin state to Hund's coupling in doped <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="normal">NdNiO</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>

The discovery of superconductivity in Nd${}_{1\ensuremath{-}x}$Sr${}_{x}$NiO${}_{2}$ has resulted a flurry experimental and theoretical work to understand the nature nickelate as compared that cuprates pnictides. Here, authors use combination LDA+U linear-response methods study magnetic exchange interactions Nd${}_{1\ensuremath{-}x}$Sr${}_{x}$NiO${}_{2}$. analysis reveals an underlying Mott insulating state comprised Ni-3${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$/Ni-3${d}_{{z}^{2}\ensuremath{-}{r}^{2}}$ orbitals with either $S$=0 or $S$=1 two-hole ground depending on precise value intra-atomic Hund's coupling.