TY - JOUR AU - Bouheroum-Mentri, Sabria AU - Benbernou, Amina PY - 2007 TI - A Priori Estimation of the Resolvent on Approximation of Born-Oppenheimer JF - Journal of Mathematics and Statistics VL - 3 IS - 2 DO - 10.3844/jmssp.2007.70.76 UR - https://thescipub.com/abstract/jmssp.2007.70.76 AB - In this study, we estimate the resolvent of the two bodies Shrodinger operator perturbed by a potential of Coulombian type on Hilbert space when h tends to zero. Using the Feschbach method, we first distorted it and then reduced it to a diagonal matrix. We considered a case where two energy levels cross in the classical forbidden region. Under the assumption that the second energy level admits a non degenerate point well and virial conditions on the others levels, a good estimate of the resolvent were observed.