Mook has conducted neutron scattering research on a broad spectrum of materials. He is best known for his pioneering research on the magnetic excitations of transition metal ferromagnets and the observation of itinerant electron effects in these materials.
For playing a substantial and lead role in developing and establishing the structural design methodology that is vital to safe and reliable nuclear power, including the development of high-temperature design analysis methods and code rules that are used worldwide.
For pioneering work on energy conservation, including development of energy demand models, data bases, and analyses of energy use trends, which has contributed to federal and state energy policies and programs and to demand-side planning by electric utilities.
For theoretical research on the electronic and vibronic structures and optical properties of defects in ionic crystals, and for work at the forefront of the rapidly developing field of laser annealing of semiconductors, leading to advances in the photovoltaic conversion of solar energy.