The Fe2+ quadrupole splitting at octahedral sites in chain silicates: Correlations with the site-distortion parameters.

Correlations between the quadrupole splitting \(\Delta E_Q \) of Fe2+ ions and the distortion of their octahedral coordination in chain silicates is presented. The distortions are quantified by the variance of the angles and by the mean quadratic elongation. It is found that \(\Delta E_Q \) initially increases very steeply with increasing distortion parameters, and subsequently shows a moderate lowering. The observed correlations are discussed in terms of the crystal‐field model.