Mapping electronic decoherence pathways in molecules

Establishing the fundamental chemical principles that govern molecular electronic quantum decoherence has remained an outstanding challenge. Fundamental questions, such as how solvent and intramolecular vibrations or chemical functionalization contribute to the decoherence, remain unanswered and are beyond the reach of state-of-the-art theoretical and experimental approaches. Here, we developed a strategy to unveil the basic chemical principles that underlie electronic quantum coherence loss for molecules immersed in condensed phase environments. By reconstructing spectral densities from resonance Raman experiments, we captured the decohering influence of the nuclear thermal environment with full chemical complexity. By decomposing the overall decoherence into contributions by solvent and specific vibrational modes, we provide much-needed means to understand how quantum coherence is lost in molecular environments. These developments connect chemical structure with quantum information science research and open a clear path toward the rational modulation of quantum coherence via chemical design and functionalization.