Spectroscopic and ultrasonic studies on the hydrogen bonded complexes of aromatic aldehydes with phenol in hexane medium

► Ultrasonic scan is carried out on ternary systems of aromatic aldehydes and phenol. ► Formation of hydrogen bonded complexes is established between phenol and aldehyde. ► Stability constant values are determined by ultrasonic & UV-vis spectral methods and compared. ► The trend in 'K' suggests that structure of aldehydes affects the stabilities of complex. ► The complex is thermodynamically stable and its formation is exothermic.