The formation of donor–acceptor pairs was detected by perturbed &ggr;&ggr; angular correlation spectroscopy. In ZnSe, ZnTe, and CdTe crystals doped with the donor111In and one of the acceptors N, P, As, or Sb the strength of the electric field gradient shows a systematic correlation of the bond length between the respective acceptor and the neighboring cation. For N acceptors, an inward relaxation of the neighboring cations is concluded to occur. ©1996 American Institute of Physics.