Abstract We present results of our Mössbauer spectroscopy study on the distribution of impurity atoms in iron based solid solutions of iron with Ti, V, Mn, Co and Ni as a solute. The results are analysed in the terms of interaction energies of impurity pairs in iron. The energies obtained for the Ti, V and Mn pairs are positive (repulsive interaction) whereas for Co and Ni pairs they are negative (attractive interaction). The data are compared with those resulting from the Miedema–Królas model for the energy. From the comparison it follows that our experimental values are in agreement with the model for Ti and V pairs but that they are in disagreement with the model predictions for Mn, Ni and Co pairs.