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σ-Aromatic MAl₆S₆ (M = Ni, Pd, Pt) Stars Containing Planar Hexacoordinate Transition Metals.

ABSTRACT: Hypercoordinate transition-metal species are mainly dominated by the 18-valence-electron (18ve) counting. Herein, we report ternary MAl₆S₆ (M = Ni, Pd, Pt) clusters with the planar hexacoordinate metal (phM) centers, which feature 16ve counting instead of the classic 18ve rule. These global-minimum clusters are established via unbiased global searches, followed by PBE0 and single-point CCSD(T) calculations. The phM MAl₆ units are stabilized by six peripheral bridging S atoms in these star-like species. Chemical bonding analyses reveal that there are 10 delocalized electrons around the phM center, which can render the aromaticity according to the (4n + 2) Hückel rule. It is worth noting that adding an (or two) electron(s) to its π-type lowest unoccupied molecular orbital (LUMO) will make the system unstable.

SUBMITTER: Bai LX

PROVIDER: S-EPMC9920543 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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σ-Aromatic MAl6S6 (M = Ni, Pd, Pt) Stars Containing Planar Hexacoordinate Transition Metals.

Bai Li-Xia LX Guo Jin-Chang JC

Molecules (Basel, Switzerland) 20230117 3

Hypercoordinate transition-metal species are mainly dominated by the 18-valence-electron (18ve) counting. Herein, we report ternary MAl6S6 (M = Ni, Pd, Pt) clusters with the planar hexacoordinate metal (phM) centers, which feature 16ve counting instead of the classic 18ve rule. These global-minimum clusters are established via unbiased global searches, followed by PBE0 and single-point CCSD(T) calculations. The phM MAl6 units are stabilized by six peripheral brid ...[more]

PMID: 36770609

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