Neutrons have many properties that make them ideal for certain types of research. Because of their unique sensitivity to hydrogen, neutrons can be used to precisely locate hydrogen atoms, enabling a more accurate determination of molecular structure, which is important for the design of new therapeutic drugs. Neutrons scattered from hydrogen in water can locate bits of moisture in fighter jet wings—signs of microscopic cracking and early corrosion that pinpoint the part of the wing that should be replaced.
Besides hydrogen, neutrons can locate other light atoms among heavy atoms. This capability is helping scientists to open the field of quantum superstates, such as superconductivity and superfluidity. Researchers are making measurements of the atomic momentum distribution of liquid 4He and are looking for a 4He supersolid state. They have determined the critical positions of light oxygen atoms in promising high-temperature, superconducting materials.