The layered $3d$ transition metal dichalcogenide ${\mathrm{CoTe}}_2$ is a topological Dirac type-II metal. However, the Co $3d$-bands in ${\mathrm{CoTe}}_2$ do not exhibit the expected correlation-induced band narrowing seen in CoO. We address this conundrum by studying the electronic structure of ${\mathrm{CoTe}}_2$ using hard x-ray photoemission spectroscopy (HAXPES), x-ray absorption spectroscopy (XAS) and resonant-PES. We quantify the on-site Coulomb energy $U_{dd}$ via single-particle partial density of states and the two-hole correlation satellite using valence band resonant-PES, and obtain $U_{dd}$ = 3.0 eV for ${\mathrm{CoTe}}_2$. Charge-transfer (CT) cluster model simulations of the experimental core-level Co $2p$ PES and $L$-edge XAS spectra of ${\mathrm{CoTe}}_2$ and CoO validate their contrasting electronic parameters: $U_{dd}$ and CT energy $\mathrm{\Delta }$ are (3.0 eV, −2.0 eV) for ${\mathrm{CoTe}}_2$, and (5.0 eV, 4.0 eV) for CoO, respectively. The $d\text{−}p$ hybridization strength $T_{eg}$ for ${\mathrm{CoTe}}_2<\mathrm{CoO}$, and indicates that the reduced $U_{dd}$ in ${\mathrm{CoTe}}_2$ is not due to $T_{eg}$. The increase in $d^n$ count $\sim 1$ by CT from ligand to Co site in ${\mathrm{CoTe}}_2$ is due to a negative $\mathrm{\Delta }$ and reduced $U_{dd}$. Yet, only because $U_{dd}>\left|\mathrm{\Delta }\right|, {\mathrm{CoTe}}_2$ becomes a topological metal with $p\to p$ type lowest energy excitations. The study reveals the connection between negative $\mathrm{\Delta }$ and reduced $U_{dd}$ required for setting up the electronic structure framework for achieving topological behavior via band inversion in the correlated metal ${\mathrm{CoTe}}_2$.

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• Electronic structure
• Topological materials
• Transition metal dichalcogenides
• Hard x-ray photoelectron spectroscopy
• X-ray absorption spectroscopy