Characterization of iron cationic sites in ferrierite using Mössbauer spectroscopy

Iron ferrierites with low iron content and well-defined cation occupation supported by FTIR, UV–vis and EPR analysis, were utilized in order to settle the Mössbauer parameters of individual iron cationic species. These samples thus could serve as standard for establishing parameters for the Mössbauer spectroscopy analysis. In accordance with the analysis and supported by the published DFT modeling iron ions were present in three types of cationic sites (one α and two β). For the first time, experimental evidence supporting the proposed existence of two types of β sites for Fe(II) bonding has been presented. Fe(II) in two types of β sites were characterized by IS = 0.92 mm/s and QS = 0.44 mm/s, and IS = of 0.94 mm/s and QS = 0.70 mm/s. The Mössbauer parameters of the Fe(II) in α sites has been established with IS = 1.02 mm/s and QS = 2.02 mm/s.