These two neutron scattering images represent the nanoscale structures of single crystals of PMN and PZT. Because the atoms in PMN deviate slightly from their ideal positions, diffuse scattering results in a distinctive butterfly shape quite different from that of PZT, in which the atoms are more regularly spaced. Neutron scattering as an experimental technique is used in crystallography, physics, physical chemistry, biophysics, and materials research. Electroceramics is a class of ceramic materials used primarily for their electrical properties. PMN, or lead zinc niobate, is a dielectric material used for construction of ceramic capacitors. PZT, or lead zirconate titanate, is one of the world's most widely used piezoelectric ceramic materials. Piezoelectricity is the electric charge that accumulates in certain solid materials (such as crystals, certain ceramics, and biological matter such as bone, DNA and various proteins) in response to applied mechanical stress. The word piezoelectricity means electricity resulting from pressure.