Volume : 5, Issue : 2, February - 2016

Acoustical Parameters on Charge Transfer Complexes of Substituted Salicyladehyes with Benzidine in n-Hexane Medium at 303K

Y Geetha, S. Chidambaravinayagam

Abstract :

<p>&nbsp;Ultrasonic velocity (U), density (&rho;) and viscosity (&eta;) have been measured for three different salicylaldehyde such as 5-chlorosalicylaldehyde, 4-diethylaminosalicylaldehyde, 3-ethoxysalicylaldehyde with benzidine in n-hexane medium at 303K. From these experimental values, the adiabatic compressibility (&beta;), acoustic impedance (Z), free length (Lf), free volume (Vf), internal pressure (&pi;i), cohesive energy (CE), Lenard Jones Potential formation constant (K), free energy of formation (?G), free energy activation (?G#) and viscous relaxation time (r) have been discussed in terms of solute- solvent and solvent-co-solute interactions. Formation constant (K) values of the compounds have been determined by using a modified Bhat equation. The values of cohesive energy (CE) and formation constant (K) are found to be high, indicating the presence of charge transfer complex between substituted aldehydes with benzidine in n-hexane medium. The complexes are thermodynamically stable as evidenced from their negative free energy of formation values and high values of molar extinction coefficient identifies the presence of strong complexes (&pi;-&pi;*, n-&pi;*) existing in these systems</p>