X-ray diffraction by a crystal in a permanent external electric field: electric-field-induced structural response in α-GaPO₄

Electric-field-induced pseudoatomic displacements in α-GaPO₄ are studied by means of an X-ray diffraction experiment. The site-selective analysis shows that the PO₄ tetrahedra are more strongly distorted compared to those of GaO₄ owing to the higher pseudoatomic charge of phosphorus.