The interaction of mercury vacancies with dopant indium atoms in Hg0.79Cd0.21Te was studied using the perturbed &ggr;&ggr; angular correlation (PAC) technique. Two dominant PAC signals, characterized by quadrupole interaction strengths &ngr;Q1=83 MHz and &ngr;Q2= 91 MHz and asymmetry parameters &eegr;1=&eegr;2=0.08, were observed and attributed to one or more In‐VHgcomplexes. The complexes appeared after annealing doped samples atT≥350 °C in vacuum and quenching. The fraction of In atoms associated with vacancies was increased further by annealing at 80 °C for ≳10 h. The In‐vacancy complexes vanished on annealing in a Hg‐saturated atmosphere.