The formation energies of a vacancy and an interstitial atom in solid krypton were calculated to be 0.114 and 0.321eV, respectively. The only stable form of interstitial was found to be the 100-split type. 

Formation Energies of Vacancies and Interstitials in Solid Krypton. R.M.J.Cotterill, M.Doyama: Physics Letters A, 1967, 25[1], 35-6