Energy spectra d3W/dE1 dE2 d cos ϑ of neutron-neutron and neutron-charged particle pairs (nn, np, nd, nt) emitted after the absorption of stopped negative pions in 6Li, 7Li, 12C, 59Co and 197Au have been measured for opening angles between 50° and 180°. Particle pairs emitted from light nuclei without energy loss due to final-state interactions were identified by the energy balance. Pion absorption on two nucleons (quasi-deuteron mechanism) was found to be the main process. The yields of nucleon pairs from quasi-free absorption on a quasi-deuteron are 0.52 ± 0.09 per π-stop, 0.57 ± 0.10 per π-stop and 0.19 ± 0.04 per π-stop for 6Li, 7Li and 12C, respectively. The ratio R of np to pp pairs that absorb the pion was determined for quasi-free absorption on p-shell nucleons of 12C: R(p-shell) = 6.3 ± 1.4. For pion absorption on s-shell nucleons of lithium lower limits R(s-shell) > 4.4 for 6Li and R(s-shell) > 7.8 for 7Li were determined. These values are larger than the statistical ratios Rstat = 2N/(Z − 1) of np to pp pairs in the nucleus. Lower limits for the probability for pion absorption on heavier clusters (3He, α) are W(hc) > 0.16 per π-stop for 6Li, W(hc) > 0.11 per π-stop for 7Li and W(α) > 0.01 per π-stop for 12C. The shape of the energy spectra of pairs emitted directly after quasi-free absorption on 2 or 4 nucleons could be explained by a simple model for the momentum distribution of the absorbing nucleons. The results are in agreement with the parameters of the momentum distributions known from other reactions. Energy spectra and opening-angle distributions were compared with the intranuclear cascade calculations of Chiang, Hüfner and Hachenberg. For 59Co and 197Au the spectra are strongly influenced by the final-state interactions; lower limits of R > 1.8 for 59Co and R > 2.5 for 197Au were determined.