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

Abstract

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 HL₁ and HL₄ showed five absorption peaks and shoulders which are assigned as π–π* and n–π* transitions. The optical energy gap (E_g) for HL₁and HL₄ 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 a semiconductor behavior. The electrical conduction mechanism was also investigated and found to be correlated barrier-hopping (CBH) and quantum mechanical tunneling (QMT) mechanisms depending on the function group. The effect of adsorbed NH₃ gas on the electrical conductivity and dielectric constants of ligand HL₃ was also investigated.