Complexes of general formula [MBr₂(3-clan)_n] (where M is Fe, Ni, Cu or Zn; 3-clan = m-chloroaniline; n is 1.5 or 2) were prepared and their characteristic properties, such as capillary MP; C, H, N, Br and metal contents; TG/DTG and DSC curves; and IR and electronic spectra were determined. By calorimetric measurements in solution, the values of some thermodynamic parameters of the complexes were determined. From these values, the standard enthalpies of the metal-nitrogen coordinated bonds were calculated, and the standard enthalpies of the formation of the gaseous phase complexes were estimated.