Thiosemicabazones as ligands—I. Spectrochemical studies on trivalent metal complexes of 1-phenyl-orthohydroxy-4-benzamido thiosemicarbazone

Synthesis, Spectral and Biological Properties of Copper (Ii) Complexes of Thiosemicarbazones of Schiff Bases Derived From 4-Aminoantipyrine and Aromatic Aldehydes.

“…In substituted thioureas, the (C=S) stretching vibrations are contributed much with some other vibrations as (CN) stretching and bending as well as (N−C−S) bending modes [32]. In the spectra of the present ligands, the bands observed in 1330-1305 cm [33] and some other authors [34,35]. Coordination of sulfur with metal ion would result in the displacement of elections toward the latter, thus resulting in the weakening of (C=S) bond.…”

“…Coordination of sulfur with metal ion would result in the displacement of elections toward the latter, thus resulting in the weakening of (C=S) bond. Hence, on complexation, (C=S) stretching vibrations should decrease and that of (CN) should increase [35,36]. In all present complexes of Cu 2+ with BAAPTS, MBAAPTS, DABAAPTS, and CAAPTS, the frequencies in 1330-1305 cm −1 get an increase by nearly 30-60 cm −1 .…”

Synthetic, structural, and antimicrobial studies of organotin(IV) complexes of semicarbazone, thiosemicarbazone derived from 4-hydroxy-3-methoxybenzaldehyde

“…The m(C=S) [25,27] and m(C=O) [25] stretching vibrations have been shifted towards lower frequency and occurred at 1,035-1,015 cm -1 and 1,710-1,695 cm -1 , respectively, in the metal complexes. This indicates that the ligands have been coordinated to the metal ions through the thionic sulphur and ketonic oxygen atoms.…”

Octahedral Co(II) and Ni(II) complexes of Schiff bases, semicarbazone and thiosemicarbazone, synthesis, biological, spectral, and thermal studies

“…The most notable change in the ligands spectral features when coordinated to metal ion is the C¼N red shift. The (C¼N) band [36][37][38][39] at 1570 cm À1 in the ligands exhibited a red shift of $40-50 cm À1 in the spectra of the complexes, evidence for participation of the C¼N group in coordination to the metal ions.…”

“…The presence of coordinated water was suggested by the very broad absorption centered around 3450 cm À1 in the infrared spectra. Bands at 930 and 770 cm À1 may be attributed to rocking and wagging modes of coordinated water [37][38][39].…”