, where γ c and γ m are the damping rates of optical cavity and molecular absorption, respectively, g is the energy exchange rate, when polymethyl-methacrylate (PMMA) was used as I-insulator in MIM. The electrical energy stored in the PMMA film plays an important role in strength of the coupling. by reflection between air-polymer and polymer-silicon interfaces had a contribution. The periodic features form the absorbance curve were subtracted as a baseline. The polyimide showed four characteristic absorption bands, with a maximum value of 0.7 µm -1 . In contrast, none of the peaks for SU-8 and OMR-100 were less than 0.2 µm -1 . These values are comparable to the other peaks of polyimide. The mid-IR intrinsic molecular fingerprint appears at wavenumbers ν˜ between 600 and 3000 cm -1 . Figure2(b) shows the modeling results of the molecular vibration analysis. It can be seen that the IR absorption spectra of the models are in good agreement with experimental spectra (Fig. ). The molar absorption coefficient ε o f t he model molecules also show similar trends to those observed in experiments α [µm ]. For each of the vibrational modes, the main component was determined. In addition, the corresponding molecular volume was determined (as per vibration mode), and it was found that there was a good correlation between the calculated and experimental results based on the data of density and molecular weight. Using these spectral results and molecular information, we were able to determine the molecular mode num- As reported previously , a method to control absorption and scattering cross sections of MIM metasurfaces was established by changing the fraction of the used metals. An increase of absorption cross-section has a high potential to control the coupling and a central wavelength of the plasmon resonance. In the present study, we investigate how the molecular absorption is affected when this coupling efficiency η is the highest. For that, a structure with film thickness of 40-50 nm had to be used. When there is no absorbing material in the insulator layer of MIM, both the plasmon resonance peaks and disk diameter have a linear relationship with a slope close to one in the log-log plot (Fig. ). Even under the weak coupling conditions, this relationship remains unchanged.