Structural and electronic properties of covalently functionalized 2-aminoethoxy-metallophthalocyanine-graphene hybrid materials: a computational study

摘要

The formation of a strong covalent bond between graphene and 2-aminoethoxy metallophthalocyanine (AEMPc) with the metal atom (M) being Zn, Fe, and Ni is established from density functional theory (DFT) based calculations at the B3LYP/6-31G(d)/LANL2DZ level of theory. The optimized structures of the hybrid complexes, represented by AEMPc-graphene, are reported. The projected density of states (PDOS) spectrum of each molecule has been calculated to explore the change in the HOMO-LUMO gap due to anchoring of AEMPc to graphene. The IR peak-positions and intensities obtained for the newly formed C-H and C-N bonds confirm the covalent link between the two moieties. The computed Raman spectra of the hybrid complexes show some changes in the relative intensities of D and G bands of graphene in accordance to those observed experimentally in a similar graphene based hybrid material. TDDFT calculations are carried out to study their absorption spectra in DMF solvent. For all three metal atoms in the composite molecules, there appears a charge transfer band in the range 600-630 nm. Three long-range corrected functionals such as M06-2X, CAM-B3LYP, and wB97XD are used to compare the results with those of the hybrid B3LYP functional.