For years, substituted iron nitrides have been studied by various types of approaches: physical, chemical, and materials engineering, both experimental and theoretical. More recently, substituted iron nitrides have been studied by theoretical models for calculation of electronic structure, presenting the advantage of being economically viable. The properties of these compounds have potential application not only as a recording material but also in other areas: as resistance to corrosion and wear. The changes occurred in the alloys when transformed into nitrides still require further studies. Thus, the electronic and magnetic structure of IrFe3 and Ir3Fe alloys and the changes caused in their ground state properties when the nitrogen atoms were included in their stoichiometry, turning them into substituted iron nitrides type Ir3FeN and IrFe3N, will be investigated in this study. The electronic structure of these compounds was modeled using the linearized augmented plane waves (LAPW), an augmented plane wave (APW - method of Slater) modification. The following methodology was used in this study: the cohesive energy for steady state was calculated and then the ground state properties, such as charge transfer, magnetic moment, hyperfine properties, and the density of states, were obtained. The ground state properties are also assessed from the pressure variation experienced by these compounds, that way, the induced changes in the alloys caused by introducing the nitrogen atom are obtained. This study may assist in obtaining new and better nitrides.