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Ionic Silver Amino Complexes Displaying Liquid Crystalline Behavior Close to Room Temperature
Author(s) -
Albéniz Ana C.,
Barberá Joaquín,
Espinet Pablo,
Lequerica M. Carmen,
Levelut Anne M.,
LópezMarcos F. Javier,
L. Serrano José
Publication year - 2000
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/(sici)1099-0682(200001)2000:1<133::aid-ejic133>3.0.co;2-1
Subject(s) - chemistry , ionic liquid , ionic bonding , crystallography , inorganic chemistry , ion , organic chemistry , catalysis
The liquid crystalline properties of a series of ionic silver complexes [Ag(NH 2 n‐ C n H 2 n +1 ) 2 ]X (X = NO 3 , n = 6, 8, 10, 12, 14; X = BF 4 , n = 8, 10, 12, 14), derived from silver nitrate or tetrafluoroborate and aliphatic amines, have been investigated by optical microscopy, DSC, and X‐ray diffraction. The materials exhibit a birefringent fluid phase identified as a smectic A mesophase by optical microscopy and X‐ray diffraction. Some of the complexes are liquid crystalline at temperatures close to room temperature. The X‐ray results are consistent with the existence in the mesophase of a bilayer organization. The silver cations adopt a U‐shape, which allows for the adoption of this bilayer arrangement, with alternating ionic and apolar regions and a short‐range square‐planar array inside the cationic sublayers. The thermodynamic parameters suggest that the melting transition clearly involves only disorder (melting) of the chains, whereas the clearing transition implies breaking the anion‐cation arrangement.