  The ability to design quantum systems that decouple from environmental noise
sources is highly desirable for development of quantum technologies with
optimal coherence. The chemical tunability of electronic states in magnetic
molecules combined with advanced electron spin resonance techniques provides
excellent opportunities to address this problem. Indeed, so-called clock
transitions (CTs) have been shown to protect molecular spin qubits from
magnetic noise, giving rise to significantly enhanced coherence. Here we
conduct a spectroscopic and computational investigation of this physics,
focusing on the role of the nuclear bath. Away from the CT, linear coupling to
the nuclear degrees of freedom causes a modulation and decay of electronic
coherence, as quantified via electron spin echo signals generated
experimentally and $\textit{in silico}$. Meanwhile, the effective hyperfine
interaction vanishes at the CT, resulting in electron-nuclear decoupling and an
absence of quantum information leakage to the nuclear bath, providing
opportunities to characterize other decoherence sources.
