Energy analyses for the alkaline-earth formates

The structures of the alkaline-earth formates have been investigated in terms of lattice energy calculations. The lattice energy E was approximated to be the sum of electrostatic and repulsive terms, where the repulsive potential used was in the form: (1/12) f(Rα + Rβ)13 r-12 (r, interatomic distance;f, arbitrarily chosen standard force; Rα, repulsive radius of an atom α). The potential parameters concerned were obtained with the structures of α-Ca(HCOO)2, α-Sr(HCOO)2 and Ba(HCOO)2. These potential parameters were successfully used for the determination of the structure of β-Sr(HCOO)2, for the differentiation of the structures of α-Sr(HCOO)2 and Ba(HCOO)2, and for the interpretation of the large anisotropy of thermal vibrations in β-Ca(HCOO)2.