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In Situ Assembled Polynuclear Zinc Oxo Clusters Using Modified Schiff Bases as Ligands.

ABSTRACT: A series of different cores and nuclearity zinc metal clusters 1-5 have been synthesized using Zn(ClO₄)₂·6H₂O, Schiff-base primary ligands, and dibenzoyl methane (DBM) or monoethanolamine (MEA) as co-ligand in a room-temperature reaction. The structure of the complexes is characterized using single-crystal X-ray diffraction. Among them, (1) [Zn(L1)(DBM)] is mononuclear; (2) [Zn₄(L2)₂(DBM)₄], (3) [Zn₄(L2)₄(H₂O)₂(ClO₄)₂]·2CH₂Cl₂, and (4) [Zn₄(L3)₂(DBM)₄] have a cubane core; and (5) [Zn₄(L4)₄(MEA)₂(ClO₄)₂] has a ladderlike core structure. Compounds 1-5 have also been characterized using UV-vis absorption and emission spectroscopies. For an in-depth understanding of the absorption spectra of 1 and 3, density functional theory (DFT) calculations have been performed, which suggest that the transitions correspond to the π → π* intraligand charge transfer (ILCT) transitions.

SUBMITTER: Mondal S

PROVIDER: S-EPMC8756576 | biostudies-literature |

REPOSITORIES: biostudies-literature

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