TY - JOUR A1 - Flad, Heinz-Jürgen A1 - Harutyunyan, Gohar A1 - Schneider, Reinhold A1 - Schulze, Bert-Wolfgang T1 - Explicit Green operators for quantum mechanical Hamiltonians BT - I. The hydrogen atom JF - Manuscripta mathematica N2 - We study a new approach to determine the asymptotic behaviour of quantum many-particle systems near coalescence points of particles which interact via singular Coulomb potentials. This problem is of fundamental interest in electronic structure theory in order to establish accurate and efficient models for numerical simulations. Within our approach, coalescence points of particles are treated as embedded geometric singularities in the configuration space of electrons. Based on a general singular pseudo-differential calculus, we provide a recursive scheme for the calculation of the parametrix and corresponding Green operator of a nonrelativistic Hamiltonian. In our singular calculus, the Green operator encodes all the asymptotic information of the eigenfunctions. Explicit calculations and an asymptotic representation for the Green operator of the hydrogen atom and isoelectronic ions are presented. Y1 - 2011 U6 - https://doi.org/10.1007/s00229-011-0429-x SN - 0025-2611 VL - 135 IS - 3-4 SP - 497 EP - 519 PB - Springer CY - New York ER -