Neutron scattering as a powerful tool in solid state chemistry.: Examples from the investigations in crystal structures and properties of metal hydrogen and metal chalcogen compounds

Neutron scattering experiments play a key role in the investigation in crystal structures and properties of solid compounds which is demonstrated with examples from the compound series A(x)M(y)X(z) (A (=) over cap alkali metal, M (=) over cap transition metal and X (=) over cap H, S or Se). Measurements on powdered samples provide as well the hydrogen positions within the crystal structures of ternary hydrides by using the analogous deuterium compounds as the lithium positions in the compounds with A (=) over cap Li. Ferromagnetic and antiferromagnetic arrangements are investigated by neutron diffraction which lead to the determination of the magnetic moments of transition metal atoms providing information about chemical bonding. Finally, it is demonstrated that inelastic neutron scattering is an independent method used in a complementary way to infrared or Raman spectroscopy, and, due to the interactions of neutrons with the magnetic states of transition metal atoms, to susceptibility or magnetisation.