[en] Several complexes of N,N'-diethylthiourea (Dietu) with zinc(II), cadmium(II) and mercury(II) halides were prepared and characterized by i.r. (4000-60 cm^-1), raman (400-60 cm^-1), in the solid state and n.m.r. and conductometric methods in solution. The complexes Zn(Dietu)₂X₂, Cd(Dietu)₂X₂ (X=Cl, Br, I) and Hg(Dietu)₂X₂ (X=Br, I) are tetrahedral species in which intramolecular -NH...X interactions have been observed. The 1:1 mercury(II) complexes, Hg(Dietu)X₂ (X=Cl, Br), appear to have a dimeric tetrahedral halide-bridged structure in the solid state. In all these complexes N,N'-diethylthiourea is sulphur-bonded to the metal. (author)