This volume records the proceedings of a Forum on The Fundamentals of
Electron Density, Density Matrix and Density Functional Theory in Atoms,
Molecules and the Solid State held at the Coseners' House,
Abingdon-on-Thames, Oxon. over the period 31st May - 2nd June, 2002. The
forum consisted of 26 oral and poster presentations followed by a
discussion structure around questions and comments submitted by the
participants (and others who had expressed an interest) in advance of
the meeting. Quantum mechanics provides a theoretical foundation for our
under- standing of the structure and properties of atoms, molecules and
the solid state in terms their component particles, electrons and
nuclei. (Rel- ativistic quantum mechanics is required for molecular
systems contain- ing heavy atoms.) However, the solution of the
equations of quantum mechanics yields a function, a wave function, which
depends on the co- ordinates, both space and spin, of all of the
particles in the system. This functions contains much more information
than is required to yield the energy or other property.