It has been recently pointed out from MEM/Rietveld analysis of synchrotron X-ray powder diffraction data that Eu@C-82 and Gd@C-82 have exceptionally an anomalous endohedral structure. However, density functional calculations reveal that the anomalous structures are highly unstable and do not correspond to energy minima. It is found that the metal atom in Eu@C-82 and Gd@C-82 is located at an off-centered position near a hexagonal ring in the C2vC82 cage, as found for M@C-82 (M=SC, Y, and La). (c) 2006 Elsevier B.V. All rights reserved.