The Faraday effect and magneto-optic anomaly of some cubic crystals

Abstract

Using a Lippich double field polarimeter together with a spectrograph, the Faraday rotation for crystals of NaCl, KCl, KBr, KI, NH₄Cl, NH₄Br, NaClO₃, KAl(SO₄)₂ 12H₂O and NH₄Al(SO₄)₂ 12 H₂O have been measured for the wavelengths λ 5893, λ 5780, λ5461, λ4358, λ4046 and λ 3665. The magnetic rotation for concentrated solutions of these crystals in water were also measured. The magneto-optic anomaly for the crystals and solutions has been calculated from the measurements of the dispersion values. It is found that in the case of crystals, γ(NaCl)>γ(KCl)>γ(KBr)>γ(KI) and γ(NH₄Cl)>γ(NH₄Br). The γ for the solutions except in the case of NaClO₃ and the alums is always greater than that for water. The γ values for the ions in solution are higher than those for the ions in the crystal. The presence of covalent bonds tends to diminish the value of γ [γ(NaClO₃ crystal)=33% and γ(Alum)=52%]. The γ value for a 50% solution of NaClO₃ is 72%.