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A non-empirical fully ionic description, with the anion wavefunctions in their compressed but still spherically symmetrical states optimal for the crystal, is presented for the cohesive energetics of two cubic phases of three solid iodides, KI, RbI and CsI. The non-correlated part of the energy is computed using the RELCRION program which takes full account of relativistic effects. Both the dispersive attractions and energies arising from electron correlations of short range are computed.For each polymorph stable under ambient conditions, the rock-salt (B1) phases of KI and RbI and the eightfold coordinated (B2) phase of CsI, the cohesion is slightly underestimated. The lattice energy deficits of around 22 kJ mol −1 for KI and RbI are reduced to around 13 kJ mol −1 for CsI, with overestimations of some 0.2 au in the equilibrium cation-anion separations R decreasing as the metal becomes more electropositive. The prediction that the B2 phase of CsI is more stable (by 6 kJ mol −1 ) than the B1 polymorph agrees with experiment. For both KI and RbI, the zinc-blende polymorph is predicted to lie some 37 kJ mol −1 in energy above the B1 polymorph.An additional potential, plausibly ascribed to slight covalency, correcting these underestimations is derived semi-empirically.

In this paper, the effect of Ti doping on the phase stability of α″-Fe16N2 was investigated. Experimental results show that appropriate Ti addition may benefit the α″-Fe16N2 phase formation. Theoretical calculation shows that the formation enthalpy of α″-(Fe,Ti)16N2 phase in (Fe,Ti)-N films is smaller than that of α″-Fe16N2 phase in Fe-N system. This suggests that the stability of α″-Fe16N2 can be enhanced by Ti addition. Therefore, the α″ alloy phase and exhibit high saturation magnetization μ0Ms=2.3—2.6T．

High moment FeNiN films with soft magnetic properties were prepared on glass and Si (100) substrates by a dual ion beam sputtering (DIBS) system. Effects of nitrogen concentrations and substrate temperatures on the phase structure and magnetic properties of FeNiN films were investigated. Nitrogen concentration of the FeNiN film was saturated to 20 at.% as nitrogen partial pressure was higher than 3 Â 10 À2 Pa. FeNiN films consisted of -(FeNi), 00 -(Fe,Ni) 16 N 2 , 0 -(Fe,Ni) 4 N phases or a mixture of these phases under different deposition parameters. The magnetic properties depended dramatically on the phase structure. FeNiN films with 8-12 at.% nitrogen concentrations deposited at 140-180 C exhibited 00 -(Fe,Ni) 16 N 2 and 0 -(Fe,Ni) 4 N phases, high saturation magnetization of 2.2-2.3 T and low coercivity of 80-110 A/m.