We performed an angle-resolved photoemission spectroscopy study of the Ni-based superconductor ${\mathrm{SrNi}}_2{\mathrm{As}}_2$. Electron and hole Fermi surface pockets are observed, but their different shapes and sizes lead to very poor nesting conditions. The experimental electronic band structure of ${\mathrm{SrNi}}_2{\mathrm{As}}_2$ is in good agreement with first-principles calculations after a slight renormalization (by a factor 1.1), confirming the picture of Hund's exchange-dominated electronic correlations decreasing with increasing filling of the $3d$ shell in the Fe-, Co-, and Ni-based compounds. These findings emphasize the importance of Hund's coupling and $3d$-orbital filling as key tuning parameters of electronic correlations in transition-metal pnictides.

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• Electronic structure
• Fermi surface
• Multiband superconductivity
• Superconductivity
• High-temperature superconductors
• Pnictides
• Strongly correlated systems
• Angle-resolved photoemission spectroscopy