Liquid Crystalline Behavior of Metal–Hydroxamates

In order to better understand the liquid crystalline behavior of recently synthesized metal hydroxamates, optical microscopy and differential scanning calorimetry have been employed. Analysis of their thermal stability and loss of mass by thermogravimetry and differential thermal analysis has been performed. The nematic mesophase can be observed in nearly all metal hydroxamates, with the exception of N-4-isopropoxyphenyl-4'-n-butoxycinnamohydroxamic acid complexes and iron hydroxamic acid complexes. Copper(II) hydroxamate complexes of N-4-n-butoxyphenyl-4'-n-butoxycinnamo hydroxamic acid and N-4-isoamyloxyphenyl-4'-n-butoxycinnamohydroxamic acid exhibit nematic as well as smectic behavior.