The recent discovery of high-$T_c$ superconductivity in Sr-doped ${\mathrm{NdNiO}}_2$ has sparked a renewed interest in investigating nickelates as cuprate counterparts. Parent cuprates $[{\mathrm{Cu}}^{2+}:d^9]$ are antiferromagnetic charge transfer insulators with the involvement of a single $d_{x^2-y^2}$ band around the Fermi level and strong $p\text{−}d$ hybridization. In contrast, isoelectronic ${\mathrm{NdNiO}}_2$ $[{\mathrm{Ni}}^{+}:d^9]$ is metallic with a $d_{x^2-y^2}$ band self-doped by Nd-$d$ states. Using first principles calculations, we study the effect of Sr doping in the electronic and magnetic properties of infinite-layer nickelates as well as the nature of holes upon doping. We find that hole doping tends to make the material more cupratelike as it minimizes the self-doping effect, it enhances the $p\text{−}d$ hybridization, and it produces low-spin ($S=0$, nonmagnetic) ${\mathrm{Ni}}^{2+}$ dopants.

• Received 5 August 2020
• Accepted 2 November 2020

DOI:https://doi.org/10.1103/PhysRevB.102.224506