The infrared absorption and 514.5 nm excited Raman spectra were measured for the metallo- tetra-(tert-butyl)-tetraazaporphyrin (MT(tBu)TAP, M--Cu, Co, Ni, Zn). The ground-state structures and vibrational spectra of MT(tBu)TAPs have been calculated at the B3LYP level of theory. The observed Raman and IR bands have been assigned based on the calculation results and by comparing with the normal metalloporphyrins. The relationship between the Raman/IR frequencies and the structures of TAP ring was investigated. The results show that the frequencies of CβCβ′ stretch (Ag), asymmetric CaNto stretch (Ag), and symmetric CaNto stretch (Bg) modes increase linearly with the decrease of the core-sizes of TAP ring. Among the three modes, the later two are more sensitive to the core-size change.
Surface Enhanced Raman Scattering (SERS) of tetrasodium meso-tetrakis (4-sulfonatophenyl) porphine (H2TSPP) and silver tetraphenylporphyrin (Ag(Ⅱ)TSPP)adsorbed spontarleously on uniform Fe3O4 colloids are recorded. The enhancement of Raman bands is approximately 30. An analysis of the SERS spectrum shows that on the Fe3O4 surface H2TSPP takes its diacid form H42+TSPP.