Atomistic lattice simulations of the ternary fluorides AMF3(A = Li, Na, K, Rb, Cs; M = Mg, Ca, Sr, Ba)

Abstract

Atomistic lattice calculations are reported of the structure and stability of the series of ternary inorganic fluorides AMF₃(A = Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺; M = Mg²⁺, Ca²⁺, Sr²⁺, Ba²⁺). The predicted low-temperature structures agree with the available experimental data, with good agreement between the experimental and theoretical lattice constants. When A⁺ and M²⁺ are comparable in size, low temperature phases with the ferroelectric lithium niobate structure are predicted. As yet no phases with this structure appear to have been observed.