We investigate the dynamical generation of isoscalar charmoniumlike states with quantum numbers $J^{PC}=0^{++},1^{++},2^{++}$, and $3^{--}$ in the mass range of 3.6 to 4.3 GeV. We employ the off-shell coupled-channel formalism, constructing kernel amplitudes from effective Lagrangians that respect heavy-quark spin-flavor and chiral symmetries. To focus solely on dynamically generated states, we explicitly exclude $s$-channel pole diagrams and include only $t$- and $u$-channel meson exchanges. Solving the integral equations, we identify six poles in the complex energy plane. In the scalar ($0^{++}$) sector, we find a bound state below the $D\overline{D}$ threshold and a resonance at $\sqrt{s_R}=(3861-i23)\mathrm{MeV}$. For the axial-vector ($1^{++}$) sector, the experimentally observed ${\chi }_{c1}(3872)$ is reproduced as a bound state near the $D{\overline{D}}^{*}$ threshold, alongside a broader resonance at $(3961-i32)\mathrm{MeV}$, which is a plausible candidate for the $X(3940)$. Furthermore, we find a narrow tensor ($2^{++}$) pole at $(4005-i6)\mathrm{MeV}$ and a ${\psi }_3$-like ($3^{--}$) pole at $(4030-i33)\mathrm{MeV}$. The present results demonstrate that coupled-channel dynamics, particularly involving the $D^{*}{\overline{D}}^{*}$ channel, play a crucial role in the formation of these charmoniumlike exotic states.

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• Exotic mesons
• Mesons
• Mass
• Parity
• Spin