Frequency-dispersive impedance analysis of CH₃NH₃PbI₃ perovskite is carried out under the external Direct current (DC) field to investigate the interplay of dielectric polarization and delocalized carrier transport. Switching of capacitance from positive to negative values is observed in the radio frequency range (42.1–42.5 MHz) for the external bias ranging from 0–4 V. The switching frequency outlined a decreasing trend with an increase in bias. Upon fitting the experimentally obtained dispersions, a bi-relaxation mechanism is unveiled. One of its constituents arises due to the typical Maxwell–Wagner interfacial polarization between the grain cores and boundaries and acts at the lower frequencies. The other one is manifested via hopping of delocalized carriers, resulting in a high frequency degenerative pseudo inductive response. The interference of these two mechanisms is manifested into an asymmetric Breit–Wigner–Fano profile of the dielectric susceptance spectra. The results are further elaborated from a theoretical point of view involving the energy band structure, electron localization function, and Mulliken charge distribution.

CH ₃ NH ₃ PbI _3的频散阻抗分析钙钛矿在外部直流电（DC）场下进行，以研究介电极化和离域载流子传输的相互作用。在0至4 V的外部偏置范围内，在射频范围（42.1–42.5 MHz）中观察到了电容从正值到负值的切换。开关频率概述了随着偏置增加而下降的趋势。在拟合实验获得的分散体后，揭示了一种双松弛机制。其成分之一是由于晶核与晶界之间的典型麦克斯韦-瓦格纳界面极化而产生的，并以较低的频率起作用。另一个通过跳离定域的载波来体现，从而导致高频简并伪感应响应。这两种机制的干扰表现为介电谱的不对称Breit-Wigner-Fano轮廓。从理论角度进一步详细阐述了结果，其中涉及能带结构，电子本地化功能和Mulliken电荷分布。