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 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.
For contributions to nuclear data measurement, analysis, and applications, through determination and development of neutron-induced reaction cross sections, high-resolution neutron scattering, the nonlocal nuclear optical model, and uncertainty and covariance information