| Abstract
| - The structural and thermal behavior of all members of the homologous series of neodymium(III) alkanoates,ranging from neodymium(III) butyrate to neodymium(III) eicosanoate are described. Neodymium(III) butyratemonohydrate, Nd(C3H7COO)3·H2O crystallizes in space group P1̄ (No. 2), Z = 2. The lattice parameters are a =9.824(2) Å, b = 11.974(2) Å, c = 14.633(2) Å, α = 86.21(2)°, β = 75.92(2)°, γ = 77.97(2)°. The crystalstructure consists of ionic layers of neodymium ions, separated by bilayers of butyrate anions. In the ionic layers,the neodymium ions are connected by bridging tridentate carboxylate groups to zigzag chains, whereas the chainsare connected among themselves by bridging bidentate carboxylate groups. The two crystallographically differentneodymium ions are both having coordination number 9, with a geometry close to a monocapped square antiprism.The structure of the higher homologues can be derived from the structure of neodymium butyrate by extendingthe alkyl chains. These compounds have a lamellar bilayer structure with planes of neodymium(III) ions coordinatedto the carboxylate groups and with the alkyl chains in an all-trans conformation. All homologous compoundsfrom neodymium(III) pentanoate to neodymium(III) pentadecanoate display a thermotropic mesophase, whichwas identified by high-temperature X-ray diffraction as a smectic A phase. For the series from neodymium(III)pentanoate to neodymium(III) undecanoate an additional high viscosity mesophase is present between the crystallinestate and the smectic A mesophase.
- The structural and thermal behavior of all members of the homologous series Nd(C3H7COO)3−Nd(C19H39COO)3 is described. The compounds a lamellar bilayer structure with planes of neodymium(III) ions coordinated to the carboxylate groups and with the alkyl chains in an all-trans conformation. All homologous compounds from neodymium(III) pentanoate to neodymium(III) pentadecanoate display a thermotropic SmA mesophase. The crystal structure of neodymium(III) butyrate monohydrate is described.
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