 At the suggestion of C. J. Gorter, the team attempted to use an oscillating field. This became the basis for the nuclear magnetic resonance method. In 1937, Rabi, Kusch, Millman and Zacharias used it to measure the magnetic moment of several lithium compounds with molecular beams, including lithium chloride, lithium fluoride and dilithium. Applying the method to hydrogen, they found that the moment of a proton was 2.785 ± 0.02 nuclear magnetons, and not 1 as predicted by the then-current theory, while that of a deuteron was 0.855 ± 0.006 nuclear magnetons. This provided more accurate measurements of what Stern's team had found, and Rabi's team had confirmed, in 1934. Since a deuteron is composed of a proton and a neutron with aligned spins, the neutron's magnetic moment could be inferred by subtracting the deuteron and proton magnetic moments. The resulting value was not zero, and had sign opposite to that of the proton. Based on curious artifacts of these more accurate measurements, Rabi suggested that the deuteron had an electric quadrupole moment. This discovery meant that the physical shape of the deuteron was not symmetric, which provided valuable insight into the nature of the nuclear force binding nucleons. For the creation of the molecular-beam magnetic-resonance detection method, Rabi was awarded the Nobel Prize for Physics in 1944.
