ABRUPT DECREASE IN SOUND VELOCITY UPON ANISOMETRIC GEL FORMATION IN A DILUTE CHIRALITY SOLUTION

Abstract

We report the phenomenon of abrupt reduction of the threshold velocity of ultrasound at a frequency of 6 MHz in a dilute homochirality solution when it undergoes a transition into the phase of the anisometric gel. The decrease observed was equal to 13% when the solute concentration was varied in the range from 0.6 to 0.8 mg/ml, i.e. when the density of the solution was changed by 0.02% (solutions of achiral analogues at these concentrations remain liquid). This is, apparently, due to the resonant interaction of ultrasonic waves with an irregular grid of the strings formed in the solution. This phenomenon allows one to evaluate the gelation threshold and is a new method for studying chiral solutions.