In a previous work the existence of an hydrogen bond between the difluoromonochloromethane (R 22) and the diethylesters of alpha-omega dicarboxylic acids was pointed out. In the present paper, the influence on absorption of substituents for the hydrogen of the CH2 has been studied in a single compound (diethylmalonate). The results show that electron acceptor substituents obstruct the forming of the hydrogen bond while electron donor substituents improve it.