Abstract The method of inelastic neutron scattering has been used to measure the frequencies of the transverse branch of phonons in Ir in the (001) and (110) directions. The results obtained are used to fit the interatomic interaction potential φ(r) for Ir, which describes with high accuracy the Ir lattice properties, including energy characteristics of point defects. The analogous potential is plotted for Rh. Specific features of φ(r) in Ir and Rh are discussed; in particular, “rigidity” at small distances and weakly pronounced Friedel oscillations. Elastic properties, phonon spectra, the formation energies of vacancies, interstitial atoms, and stacking faults, as well as the migration energies of vacancies, and interstitial atoms in Ir and Rh, are calculated.