Electron-rich ligand modified, ferromagnetic luminescent cis-[CoIII(en)2(RNH2)Cl]Cl2 complexes and their electrochemical reduction behavior

Unveiling photoinduced electron transfer in cobalt(iii)-R-pyridine complexes anchored to anatase nanocrystals: photoluminescence and magnetic studies

“…Typically, [Co(N–N) 2 LX] 2+ type molecules exhibit vibrations at 910–800 cm −1 in the –CH 2 rocking region, with cis complexes manifesting more bands in this region than trans complexes. 31,32 In this study, bands at ∼812, ∼868, and ∼910 cm −1 confirm the –CH 2 rocking region, affirming the coordination of 1,3-propanediamine molecules to the metal ion. The band at 1617 cm −1 is assigned to the heterocyclic ring vibration, indicating coordination of the nitrogen atom of the 4-substituted pyridine ligand with the metal ion.…”

“…Bands in the 1320 cm −1 region, corresponding to NH 2 deformation, further confirm the structural similarity of the Co( iii ) complexes to the earlier proposed [Co(en) 2 (RNH 2 )Cl] 2+ ion. 31 Distinctive bands at 1458 cm −1 and 1578–1590 cm −1 are observed, corresponding to CC and CN vibrations of the pyridine ring, respectively. Additionally, bands at ∼589 cm −1 and ∼590 cm −1 corresponding to Co–N(tn) and Co–N of NH 2 (tn) bending, respectively, are exhibited around 1650 cm −1 .…”

“…† Analysis of the IR data reveals distinctive peaks in the range of 3500 to 3400 cm −1 , attributable to the antisymmetric and symmetric n(O-H) stretching modes of lattice-bound water. 31 The existence of stretching absorption bands within the range of 1650-1620 cm −1 affirms bending modes associated with n(O-H), signifying the potential presence of the hydrated form of the molecule through hydrogen bonding in some of the complexes. 26,32 However, it's important to note that this characteristic is not illustrated in the single crystal studies of the representative complex (4) discussed in the subsequent sections.…”