Diffusion Measurement of Mn+ + in Single-Crystal NaCl Using Electron Spin Resonance Absorption Intensity

Electron paramagnetic resonance intensity measurements were used to ascertain the diffusion parameters of Mn+ + in NaCl. It was found that for high concentrations the diffusivity was essentially concentration-independent and could be described by the equation D = D0 exp(—φ/kT) over the entire range of temperatures investigated. The parameters were D0= (3.48±1.32)×10−3 cm2/sec and φ=0.954±0.037 eV. Diffusion was from a large source deposited from solution on the surface of a polished NaCl crystal. After a diffusion anneal in an inert atmosphere the crystals were sectioned with a microtome. The collected sections were placed in special sample tubes and run in an X-band spectrometer. Relative intensity measurements were used to find the appropriate concentration curves.