The Jahn-Teller distortion mechanism in the Nd_2−x Ce _x CuO₄ is analyzed. This analysis is based on a quasi-molecular model for the CuO₄ cluster havingD _4h symmetry. In order to compare with experimental Mössbauer measurements in the doped Nd_1.85Ce_0.15Cu_0.99Fe_0.01O_4−δ superconductor, the FeO₄ cluster is also analyzed for the case of Fe²⁺ in the high spin state. The results show not evidence of a Jahn-Teller effect in these superconductors.