Journal Article 2 N-representability 2 density matrix 2 quantum crystallography 2 Clinton equations 1 Research Support, Non-U.S. Gov't 1 Research Support, U.S. Gov't, Non-P.H.S. 1 plus ... X-ray diffraction 1 electron density 1 idempotent density matrix 1 kernel energy method 1 projector density matrix 1 quantum theory of atoms in molecules 1 soft scaling quantum chemical methods 1 water clusters 1 moins ...