The paper titled “Quadrupole Excitation in Tunnel Splitting Oscillation in Nanoparticle Mn12” [1], published in Advances in Condensed Matter Physics, has been retracted as it is found to contain a substantial amount of material, without referencing, from the paper “Ground State Tunnel Splitting in Mn12 Acetate, undergraduate Senior Honors Thesis (Amherst College),” Micheal Foss-Feig, 2006.