Metal precipitation has been observed at the 2D crystals of alkylammonium metal chlorides, (CnH2n+1NH3)2MCl4 which were X- or (gamma) -irradiated at 77 K and warmed to room temperature. It has been also observed in the 1D crystals of CsMnCl3(DOT)2H2O which was irradiated at room temperature similar as photochromism of silver halides. The different temperature conditions of metal precipitation suggest a variety of defect formation mechanisms. In alkylammonium metal chlorides, Cl2- molecule ions are formed at 77 K and electron trap centers are observed at 15 K with X-ray irradiation. The electron trap centers are very unstable and are bleached at temperatures higher than 30 K.