Supramolecular Co(II) complexes based on dithiolate and dicarboxylate ligands: Crystal structures, theoretical studies, magnetic properties, and catalytic activity studies in photocatalytic hydrogen evolution

Adhikari S., Sheikh A. H., Kansiz S., DEGE N., Baildya N., Mahmoudi G., ...More

JOURNAL OF MOLECULAR STRUCTURE, vol.1285, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 1285
  • Publication Date: 2023
  • Doi Number: 10.1016/j.molstruc.2023.135481
  • Journal Name: JOURNAL OF MOLECULAR STRUCTURE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, INSPEC
  • Keywords: Supramolecular assemblies, Co(II), Crystal structures, Hirshfeld surface analysis, Magnetic studies, Photocatalytic hydrogen evolution, BRIDGED COPPER(II) COMPOUNDS, ION-PAIR RECEPTOR, COBALT(II) COMPLEXES, DINUCLEAR COBALT(II), CARBOXYLATO BRIDGES, EFFICIENT, DERIVATIVES, REDUCTION, BEHAVIOR, BINDING
  • Ondokuz Mayıs University Affiliated: Yes

Abstract

Two supramolecular Co(II)-based coordination compounds have been harvested from dithiolate and di-carboxylate ligands. They have been structurally characterized by FT-IR, elemental analysis, and sin-gle crystal X-ray diffraction. Salt 1 consists of two ([tris (2-aminoethyl) amine Co] 1,1-dicyano-2,2-ethylenedithiolate)+ per thiosulphate ion linked through intermolecular hydrogen bonds. Compound 2 , (pyridine-2,6-dicarboxylate)2Co-5H2O -Co).2H2O, is stabilized by intramolecular O -H center dot center dot center dot O hydrogen bonds, building ribbons that propagate along the [100] direction in the crystals. From HS analysis, it is observed that the major non-covalent interactions present in 1 are C -H center dot center dot center dot O, N -H center dot center dot center dot N, N -H center dot center dot center dot S, and N -H center dot center dot center dot O hy-drogen bonds, which play an important role in stabilizing the crystal structure. In 2 , out of all the non -covalent interactions, O center dot center dot center dot H/H center dot center dot center dot O interactions have major contributions to stabilize the crystal structure. Theoretical investigation on the molecular structures of the crystals also revealed that the major stabi-lizing factor for 1 is H-bonding along with pi-pi stacking while that for 2 is co-ordinate bond between water and cobalt(II) ion. Direct current variable-temperature magnetic susceptibility measurements car-ried out on polycrystalline samples of 1 and 2 in the temperature range of 1.8-300 K shows the presence of magnetic anisotropy of the cobalt(II) ion in 1 and weak intermolecular exchange in 2 . Further, both the compounds 1 and 2 are found to be highly efficient water reduction catalysts in terms of per Co turn-over-numbers at lower concentrations.(c) 2023 Elsevier B.V. All rights reserved.