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Main-group metal cyclophane complexes with high coordination numbers.

ABSTRACT: Density functional theory calculations using the PBE0-D3BJ hybrid functional have been employed to investigate the complexation of main-group metal-cations with [2.2.2]paracyclophane and deltaphane. Geometry optimization under symmetry constraints was performed to observe the mode of coordination that a metal-cation adopts when it resides inside the cyclophane cavity. Thermodynamic properties were investigated to note the trends of stability along a group of metals. To further investigate the bonding properties, Morokuma-Ziegler energy decomposition analysis, natural bond orbital analysis and Bader's analysis were employed. It was observed that most of the main-group metal complexes with cyclophanes prefer an η⁶η⁶η⁶ coordination mode where the metal-cation sits in the centre of the cyclophane cavity. There is an increased thermodynamic stability in [2.2.2]paracyclophane complexes compared to their deltaphane analogues while the reverse is true regarding the strength of coordination based on interaction energy.

SUBMITTER: Altaf Y

PROVIDER: S-EPMC9056411 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Main-group metal cyclophane complexes with high coordination numbers.

Altaf Yasir Y Yar Muhammad M Hashmi Muhammad Ali MA

RSC advances 20200820 51

Density functional theory calculations using the PBE0-D3BJ hybrid functional have been employed to investigate the complexation of main-group metal-cations with [2.2.2]<i>para</i>cyclophane and deltaphane. Geometry optimization under symmetry constraints was performed to observe the mode of coordination that a metal-cation adopts when it resides inside the cyclophane cavity. Thermodynamic properties were investigated to note the trends of stability along a group of metals. To further investigate ...[more]

PMID: 35516020

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Main-group metal cyclophane complexes with high coordination numbers.

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Main-group metal cyclophane complexes with high coordination numbers.

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