Abstract
The author is concerned with the fields of stress and electric displacement, in a piezoelectric hexagonal crystal, caused by infinite straight defects; dislocations and disclinations, that belong to its hexad axis. Computations are made for those fields in crystals of classes 6, 622, 6mm and m2. In the crystal of class 6, the complete analytical solutions are presented. In the absence of the piezoelectric effect, the expressions for the stress field become coincident with those given hitherto. In class
m2, the complex solutions are presented; the expressions for the fields of defects are given as their imaginary part. Finally, the dilatational fields produced by the disclination-dipole are illustrated for caesium copper chloride, zinc oxide and gallium selenide, as well as the components of the electric-displacement field for zinc oxide and gallium selenide.
Acknowledgements
Computations of residues and integrals, and the drawing of figures, were made by the aide of the softwares from the Mathematica package, v.2.2, by Wolfram Research.