alternating current polarography square-wave polarography An electrochemical technique where the ac component of the cell current is measured as a function of time and as a function of the ac potential between the indicator and reference electrodes. The working electrode is a dropping mercury (or other liquid conductor) electrode and unstirred solutions are used. The cell current is sampled (only once per drop lifetime) on alternate half cycles and the potential is applied as a large amplitude square wave superimposed on a linear sweep. square wave polarography CHMO:0000035