Proton and deuteron magnetic resonance in single crystals of Fe(NH4)2(SO4)2∙6H2O

Abstract

Single crystal proton and deuteron magnetic resonance in Fe(NH4)2(SO4)2∙6H2O and Fe(ND4)2(SO4)2∙6D2O, respectively, are studied at room temperature. From the proton magnetic resonance study are found the orientations of the proton–proton vectors of the water molecules with respect to the crystallographic axes. Proton resonance data are used to determine the positions of the hydrogen atoms belonging to the water molecules in the crystal. A deuteron resonance study shows that the D2O molecules are flipping fast at room temperature. The quadrupole coupling tensor at the deuteron sites of D2O in the crystal are determined. The positions of the hydrogen atoms are also determined from the directions of the principal components of the quadrupole coupling tensor.