<p>The push for electrification in chemical engineering is accelerating the development of efficient technologies for external field intensification, such as microwave. These technologies aim to maximize the utilization of matter and energy. However, the emergence of fluid structure at nano-/microscopic levels, combined with the complex interactions between interfacial effects and microwave, poses significant challenges to existing theoretical frameworks. Traditional thermodynamic models, which rely on macroscopic experimental data within a phenomenological approach, may not accurately capture the precise variations in fluid structures at interfaces with microwave applied. In this perspective, we begin with quantum mechanics and propose the concept of equivalent potential, providing a fundamental principle to unify the impacts of interface and microwave. Meanwhile, the importance of fluid structure regulation within the framework of equivalent potential has been discussed, promoting deeper exploration of both thermal and nonthermal microwave effects. Looking ahead, the ongoing development and application of novel theoretical methods that decouple interfacial effects from external field effects, alongside advancements in <i>in situ</i> spectral characterization technologies, are expected to establish a paradigm based on the microscopic fluid structure regulation that better facilitates the utilization of microwaves in modern chemical engineering.</p>