Mn(DMPDA)M(CN)4.2C6H6 (M = Cd, Hg or Zn; DMPDA = 2,2-dimethyl-1,3-diaminopropane) and Cd(DMPDA)M(CN)4.C6H6 (M= Cd or Hg) Hofmann-Td-type clathrates were synthesized and characterized by vibrational spectroscopy. Infrared spectra of Mn(DMPDA)M(CN)4.2C6H6 (M = Cd, Hg or Zn; DMPDA = 2,2-dimethyl-1,3-diaminopropane), the vibrational spectra of Cd(DMPDA)M(CN)4.C6H6 (M= Cd or Hg) were reported. All the vibrational modes of coordinated DMPDA were characterised. The spectral features suggested that these compounds were similar in structure to the Hofmann-Td-type clathrates.