| Abstract
| - 4-Alkoxybenzoic acids are well-known liquid crystals. The rigid core of the mesogen isformed by intermolecular hydrogen bonds. Layered structures with characteristics thatdepend on the lanthanide ion are formed when a trivalent lanthanide ion is introduced.Also, the chain length influences the structure and hence the thermal behavior of thesecomplexes. Lanthanide complexes of 4-butyloxybenzoic acid have a low crystallinity, whereasmetal complexes with longer chain lengths display several types of layered structures. Thethermal behavior of lanthanum(III) and holmium(III) 4-butyloxybenzoate, 4-hexyloxybenzoate, 4-octyloxybenzoate, 4-nonyloxybenzoate, and 4-decyloxybenzoate is discussed, relyingon differential scanning calorimetry (DSC), thermooptical microscopy, and synchrotron X-raydiffraction data. A smectic A mesophase was observed for lanthanum(III) 4-hexyloxybenzoate,lanthanum(III) 4-octyloxybenzoate, and lanthanum(III) 4-nonyloxybenzoate. The corresponding holmium(III) compounds are not liquid crystalline.
- The thermal behavior of a series of lanthanum(III) 4-alkoxybenzoates and holmium(III) 4-alkoxybenzoates has been investigated by differential scanning calorimetry (DSC), polarizing microscopy, and synchrotron X-ray diffraction. The compounds were found to exhibit different types of layered structures. Mesomorphism was exhibited by the lanthanum(III) complexes, but not by the corresponding holmium(III) compounds.
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