Norman Elliott

Magnetic structures of 3d transition metal double fluorides, KMeF3

The antiferromagnetic structures of KCrF3, KMnF3, eF3, KCoF3, KNiF3, and KCuF3 were obtained by neutron fraction. The manganese, iron, cobalt, and nickel doufluonides exhibited an order in which the divalent 3d ion as coupled antiferromagnetically to its six nearest neighbors. In the chromium double fluonide, the magnetic structure consisted of ferromagnetic (001) sheets, coupled antiferromagnetically along the STA001! direction. No magnetic ning was observed in the neutron d fraction pattern copper double fluoride. The magnetic structures and served crystallographic distortions are discussed in of an indirect exchange mechanism and in terms of the crystal field theory, respectively. (auth)

Interatomic Distances in FeS2, CoS2, and NiS2

The crystal structures of FeS2, CoS2, and NiS2 have been re‐examined. The sulfur‐sulfur distances are found to vary, depending on the number of antibonding electrons shared with the metal ions.

Magnetic Moments of V2+, Cr3+, and Mn4+ Ions in Octahedral Ligand Fields

The magnetic susceptibilities of V (bipy)3(ClO4)2, K3Cr(CN)6, and K2MnCl6 have been measured in the temperature range of liquid‐nitrogen to room temperature. The magnetic moments of the ions, V2+, Cr3+, and Mn4+ agree, within experimental error, with the spin‐only moment, 3.87 β.

Magnetic Behavior of the System CoO–MgO at Elevated Temperatures

The magnetic susceptibilities of solid solutions of CoO and MgO have been measured at elevated temperatures. The data fit a Curie‐Weiss law ξ = C/(T+Θ) with C = 3.23±0.04. Θ varies linearly with the mole fraction of CoO. The magnetic measurements indicate that CoO has an antiferromagnetic ordering of spins of the first kind below the Curie point.

Equilibrium in the Exchange of Deuterium between Ammonia and Hydrogen

Equilibrium in the reaction NH3(g)+HD(g)=NH2D(g)+ H2(g) was measured in the temperature range 210°K to 295°K. The results may be expressed by the relation K=0.972 exp 509/T. The zero‐point energy difference between NH3 and NH2D is calculated to be 635±3 cm−1.

Paramagnetic Susceptibilities of Solid Solutions of MnF2 and ZnF2

The paramagnetic susceptibilities of solid solutions of MnF2 and ZnF2 have been measured as a function of temperature. The Curie‐Weiss law X=C/T+Δ is obeyed by all the solutions examined over the temperature range 76°—295°K. The constant Δ was found to be a linear function of the mole fraction of MnF2. This behavior is consistent with the assumption that the magnetic interaction energy associated with a given ion is proportional to the number of its paramagnetic neighbors.

Magnetic Susceptibilities of K3MoCl6 and RuCl3

Magnetic susceptibilities of K3MoCl6 and RuCl3 were measured in the temperature range 76°—297°K. Curies law is obeyed by both salts. The magnetic moments 3.83β and 2.07β are calculated for the ions Mo3+ and Ru3+, respectively.

Crystal structures and magnetic properties ofA2MnCl6 salts (A = NH4+, K+ and Rb+)

The temperature dependence of the magnetic susceptibility ofA2MnCl6 salts (A = NH4+, K+, Rb+) has been measured, and their crystal structures determined using powder X-ray diffraction methods. The structures of these simple cubic salts are governed by thex coordinate of the halide ion. The magnetic and the structural data suggest the presence of antiferromagnetic interactions between adjacent MnCl62− octahedra across bridges of the type as were found in related iridium salts: the susceptibility and the structural data have been used to estimate separately the values of ratios of the exchange integrals between pairs of salts; the agreement is better than 6 %.

THE MAGNETIC SUSCEPTIBILITY OF URANIUM TETRACHLORIDE

The magnetic susceptibility of UCl4 has been measured in the temperature range 76°—354°K. The molar susceptibility is given by the equation, χmole=1.22/(T+39∘).

Paramagnetism of Tetraphenanthroline Dihydroxyl Diferric Chloride

The magnetic susceptibility of ferric o‐phenanthroline has been measured and found to show abnormal temperature dependence. The results are explained in terms of an equilibrium between a singlet ground state and an excited triplet state of the dimer.