Position space electron density 440 Subject

If a substance forms crystals, it may be subjected to X-ray analysis. Such an analysis is quite exceptional, since it is one of very few techniques (which also include neutronography and nuclear magnetic resonance spectroscopy), which can show atomic positions in space. More precisely, the X-ray analysis shows electronic density maps because the radiation sees electrons, not nuclei. The inverse is true in neutronography. If we have the results of X-ray and neutron scattering, we can subtract flie electron density of atoms (positions shown by neutron scattering) from the electron density of the molecular crystal (shown by X-ray scattering). This difference would be a result of the chemical bonding (and, to a smaller extent, of the intermolecular... 

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