Optical and dielectrical properties of 2-hydroxy-1-naphthylideneaniline and its derivatives

The optical and electrical properties of 2-Hydroxy-1-naphthylideneaniline and its 
derivatives (HL n) have been investigated. The spectral distribution of absorption (α) 
coefficient for the ligands HL 1 and HL 4 showed five absorption peaks and shoulders which 
are assigned as π–π* and n–π* transitions. The optical energy gap (E g) for HL 1 and HL 4 
is investigated and found to be in the range of 2.09–2.27 eV depending on the function 
group and the type of electronic transition. The ac conductivity measurements showed