First-principles total energy calculations of the structural and electronic properties of Ce-doped fullerene have been performed within the framework of the density functional theory at the generalized gradient approximation level. Among various locations, Ce atom was found to engage with the six-fold carbon ring. The total energy is found to significantly change as the Ce atom being shifted from the center of the cage toward the edge close to the six-membered ring where the total energy reaches its local minimum. Moreover, repulsive interaction between Ce atom and the cage components turns as the adatom directly interacts with the six C atoms of the ring. The lowest-energy CeC60 geometry is found to have a binding energy of approximately 5.34？eV, suggesting strong interaction of the dopant with the cage members. Furthermore, fundamental key structural parameters and the total density of states of the optimized structure have been determined and compared with the available data. 1. Introduction Nowadays, the interest in nanoscale materials has rapidly increased due to their positive use in various technical and scientific researches relating on the energy, environment, and biomedical fields. Carbon is one of the most amazing elements with a vast range of exotic properties. These properties have shed the light on carbon-based nanostructures, such as fullerenes [1], carbon nanotubes [2], and graphene [3]. Since its discovery in 1985 (Nobel Prize in 1996) [1], the subject of fullerene molecule C60, the closed-cage carbon molecules, has attracted immense interest and attention due to its fascinating chemical and physical properties [4–7]. Indeed, the discovery of fullerenes has opened the gate for the production and investigation of much more suitable material building blocks which could be used as drug deliverers in medical applications and/or possible superconductors in technological applications. Therefore, fullerene provides an entirely new branch of chemistry, materials science, and physics. Moreover, solid fullerene is treated as a semiconductor material [8], and its structure is described in the face-centered cubic lattice. Unlike the carbon nanotubes with only hexagonal cells, the fullerene consists of both pentagons and hexagons with two classes of bond lengths: a shorter bond length connecting two successive hexagons and a longer bond length joining a hexagon and pentagon. While the dependence of properties at nanoscale provides an opportunity to test and experiment with various materials, the fullerene is considered as a suitable candidate for
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