Local symmetry of copper sites in ${\mathrm{La}}_{2\mathrm{-}\mathit{x}}$${\mathrm{Sr}}_{\mathit{x}}$${\mathrm{CuO}}_4$

Nuclear quadrupole and magnetic resonances of copper ions in ${\mathrm{La}}_{1.84}$${\mathrm{Sr}}_{0.16}$${\mathrm{CuO}}_4$ have been performed at temperatures between 300 and 5 K. The analysis of the spectra shows that there are two electronically distinct copper sites for which the symmetry of the electric-field-gradient tensors is uniaxial with the principal axis along the crystal c axis. This result constrains possible structural models.