Research Information System
Journal of Molecular Structure, vol.1361, 2026 (SCI-Expanded, Scopus)
In this study, two new cobalt(II) complexes were prepared using the known SAV-A1-derived dithiophosphonate ligands (from 2,4-bis(3,4-dimethoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-disulfide), and their structural features were investigated. The ligands were obtained by first exposing SAV-A1 to alcohols and then introducing ammonia gas, after which they were reacted with cobalt(II) salts to form the complexes [Co(L1)2(aq)] and [Co(L2)2(aq)]. The complexes were characterized using standard spectroscopic (FT-IR, MS-MALDI-TOF, and elemental analysis) and crystallographic methods, supported by magnetic susceptibility measurements confirming the presence of high-spin Co(II) species. Single-crystal X-ray diffraction revealed that both complexes adopt a rarely encountered five-coordinate geometry, where two chelating dithiophosphonate ligands and one water molecule resulting in a distorted trigonal-bipyramidal CoS4O core. Hirshfeld surface and 2D fingerprint analyses revealed that O–H···O, C–H···O, and C–H···S interactions significantly contribute to stabilization within the crystal lattice. Furthermore, complementary DFT calculations (B3LYP/LANL2DZ) were used to optimize and characterize the geometries, electronic structures, and molecular electrostatic potential surfaces, with the optimized geometries showed close agreement with the X-ray crystallographic data.