 The electron-nuclear enhancement predicted by Overhauser was experimentally demonstrated in 7Li metal by T. R. Carver and C. P. Slichter also in 1953.A general theoretical basis and experimental observation of an Overhauser effect involving only "nuclear" spins in the HF molecule was published by Ionel Solomon in 1955.Another early experimental observation of the NOE was used by Kaiser in 1963 to show how the NOE may be used to determine the relative signs of scalar coupling constants, and to assign spectral lines in NMR spectra to transitions between energy levels.