Electrogyration and piezogyration in NaClO₃

A method is developed for measuring electrogyration and piezogyration effects in polar crystals. The influence of linear electro-optic and piezo-optic effects is discussed in detail. By the use of different directions of measurement, the tensorial behaviour of the induced gyration is proved unequivocally. The magnitudes of the electrogyration and piezogyration coefficients are 10^-16 m V^-1 and 10^-15 m² N^-1 respectively. The relations between constants measured under different thermodynamic conditions are considered. An analysis of results on the basis of a coupled oscillator model reveals a strong sensitivity of induced gyration to changes in the arrangement of the oscillators.