Current formulations of nonequilibrium thermodynamics of open chemical reaction networks only consider chemostats as free-energy sources sustaining nonequilibrium behaviors. Here, we extend the theory to include incoherent light as a source of free energy. We do so by relying on a local equilibrium assumption to derive the chemical potential of photons relative to the system they interact with. This allows us to identify the thermodynamic potential and the thermodynamic forces driving light-reacting chemical systems out-of-equilibrium. We use this framework to treat two paradigmatic photochemical mechanisms describing light-induced unimolecular reactions—namely, the adiabatic and diabatic mechanisms—and highlight the different thermodynamics they lead to. Furthermore, using a thermodynamic coarse-graining procedure, we express our findings in terms of commonly measured experimental quantities, such as quantum yields.

中文翻译：

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光诱导反应的非平衡热力学

当前开放化学反应网络的非平衡热力学公式仅将恒化器视为维持非平衡行为的自由能源。在这里，我们扩展了理论，将非相干光作为自由能的来源。我们通过依赖局部平衡假设来推导光子相对于它们相互作用的系统的化学势。这使我们能够确定驱动光反应化学系统失去平衡的热力学势和热力学力。我们使用这个框架来处理描述光诱导单分子反应的两种典型光化学机制——即绝热和非绝热机制——并强调它们导致的不同热力学。此外，使用热力学粗粒度程序，