LiMnO2 is one of only a few ternary oxides which are known to form in the orthorhombic Pmmn structure. The layered α-NaFeO2 structure, favored for application as a Li-insertion electrode, is found in many other alkali transition metal oxides. We find that the the strong antiferromagnetic interactions between Mn+3 ions contribute to the stabilization of the orthorhombic structure. Using first-pr...

A second, monoclinic, polymorph of the title compound, C(14)H(8)Cl(2), has been found. In addition to the structure of this monoclinic form, the structure of the previously described orthorhombic form [Desvergne, Chekpo & Bouas-Laurent (1978). J. Chem. Soc. Perkin Trans. 2, pp. 84-87; Benites, Maverick & Fronczek (1996). Acta Cryst. C52, 647-648] has been redetermined at low temperature and usi...

We study the energetics of quasicrystals using a lattice gas simulation to sample atomic conngurations close to the quasicrystal and its approximants. The total potential energy for each connguration is calculated by summing electronic structure based pair potentials. We apply this method to study Al 73 Co 24 in a 14.4 A by 12.3 A by 8.1 A orthorhombic cell. The structures obtained are compared...