The Principal Magnetic Susceptibilities of Single Crystals of Rare Earth Salts at Low Temperatures. Part III—Neodymium Salts

The principal susceptibilities of neodymium salts have been measured from room temperature down to liquid air temperature. The results are discussed in terms of Crystalline Field Theory. It is found that (1) though the mean susceptibility can be explained satisfactorily on the basis of a single cubic field even of the fourth degree, the absolute magnitude of the fourth order cubic field estimated in this manner from the magnetic data will not be correct, (2) the cubic part of the field in the various neodymium salts estimated from magnetic data on the assumption that the cubic part of the field is wholly of the fourth degree, is found to vary markedly from crystal to crystal. (3) The influence of the fourth and six degree terms of the cubic field on the Stark splitting of the rare earth ions and in crystals, and their large magnetic anisotropy go to show that the low lying energy levels as observed in absorption spectra cannot be attributed to cubic field alone.(4)The X1—axis of neodymium sulphate rotates by about 7a In the range studied

The Principal Magnetic Susceptibilities of Single Crystals of Rare Earth Salts at Low Temperatures. Part II. Praseodymium Salts

The principal susceptibilities of praseodymium salts have been measured from room temperature down to liquid air temperature, The results are discussed in terms of the crystalline electric field theory. It is found that (1) on the basis of a single Suitable cubic field the observed magnetic moment at all temperatures in the range studied can be explained satisfactorily. (2) The observed large anisotropies of the crystals point to the existence 0f strongly asymmetric rhombic field. (3) a rough estimate of the rhombic part of the field shows that the splitting by it is by no means small and compares favorably with the cubic splitting. (4) The X1-axis of praseodymium sulphate rotates by about 63 degrees in the range studied

Light Absorption in NO2 Ion in State of Solution (Part III- Effect of Cation)

200mμ band, which is an allowed π-π* transition has been studied in five monovalent nitrates. The blue shift of the band has been found to be proportional to the inverse of the cationic radius