EN
We tried to detect a strain in the crystal induced by the ordering of the EL2 defects in the metastable state by measuring linear dichroism and birefringence. We found that this strain is below the detection limit of our experiments and lower than that induced by 1 MPa of external stress. The observed dependence of orientation of the EL2 defects in the metastable state on the polarization of light used to transform EL2 to the metastable state is consistent with the attribution of the metastability of EL2 to the transformation of the isolated As_{Ga} to the V_{Ga}A_{Si} defect and is in conflict with the As_{Ga}-A_{Si} defect pair model of EL2.