In order to understand how ions transfer in water, a study emphasizing the vibrational structures and energy levels is important. In this computational work, we used different ab initio methods and basis sets in order to find the most accurate and cost effective computational approach to predict the structure and vibrational spectra of hydrated ions H3O2? and H5O2+. Furthermore, while using these methods, the vibrational frequencies of hydrated ions were obtained by normal mode analysis (NMA) using the program Gaussian and visualized by Molden program. The infrared spectra were calculated by molecular dynamics (MD) simulations at temperatures 100 K and 300 K and attention was given to the prediction of the proton transfer frequencies. Furthermore, deuterium structures D3O2? and D5O2+ were also studied in the same manner to help assign spectral features. Lastly, a comparison of vibrational frequencies from normal mode analysis and molecular dynamics was performed to make spectral assignment. The spectra obtained from our theoretical simulations were also compared to available experimental results for accuracy and spectral shifts due to isotopic variation.