The enthalpies of solution of deutero- and hematoporphyrin and their comple
xes with Zn(II) and Cd(II) in benzene, chloroform, and tetrachloromethane w
ith imidazole admixtures were measured calorimetrically at 298.15 K. The en
thalpy contribution of imidazole extracoordination by metalloporphyrins was
estimated. The influence of structural characteristics of the solvation sh
eaths of porphyrins on the enthalpy characteristics of interparticle intera
ctions is discussed.