The N-hexadecylpyridinium derivatives [C16-Py]2[MCl4] (M=Cd (1), Zn (2)) were prepared and structurally characterized by X-ray diffraction methods. The crystal structure of 1 reveals a layered arrangement with alternation of monolayers of interdigitated cations with layers of isolated [CdCl4]2- anions. C-H⋯Cl-Cd interactions reinforce the association between anions and cations in the polar region of the supramolecular structure. Both 1 and 2 display a thermotropic smectic A phase in addition to some high-temperature crystalline modifications. The thermal polymorphism of the salts was studied by X-ray powder diffraction, differential scanning calorimetry (DSC), and thermal optical microscopy. The structural and mesomorphic characteristics of 1 and 2 are compared with those of the analogous salts along the series [C16-Py]2[MCl4] (M=Co, Ni, kCu, Zn, Pd, Cd).
Crystal architecture and mesophase structure of long-chain N-alkylpyridinium tetrachlorometallates / F., Neve; Francescangeli, Oriano; A., Crispini. - In: INORGANICA CHIMICA ACTA. - ISSN 0020-1693. - 338:(2002), pp. 51-58. [10.1016/S0020-1693(02)00976-3]
Crystal architecture and mesophase structure of long-chain N-alkylpyridinium tetrachlorometallates
FRANCESCANGELI, ORIANO;
2002-01-01
Abstract
The N-hexadecylpyridinium derivatives [C16-Py]2[MCl4] (M=Cd (1), Zn (2)) were prepared and structurally characterized by X-ray diffraction methods. The crystal structure of 1 reveals a layered arrangement with alternation of monolayers of interdigitated cations with layers of isolated [CdCl4]2- anions. C-H⋯Cl-Cd interactions reinforce the association between anions and cations in the polar region of the supramolecular structure. Both 1 and 2 display a thermotropic smectic A phase in addition to some high-temperature crystalline modifications. The thermal polymorphism of the salts was studied by X-ray powder diffraction, differential scanning calorimetry (DSC), and thermal optical microscopy. The structural and mesomorphic characteristics of 1 and 2 are compared with those of the analogous salts along the series [C16-Py]2[MCl4] (M=Co, Ni, kCu, Zn, Pd, Cd).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
