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Breaking a dative bond with mechanical forces.

ABSTRACT: Bond breaking and forming are essential components of chemical reactions. Recently, the structure and formation of covalent bonds in single molecules have been studied by non-contact atomic force microscopy (AFM). Here, we report the details of a single dative bond breaking process using non-contact AFM. The dative bond between carbon monoxide and ferrous phthalocyanine was ruptured via mechanical forces applied by atomic force microscope tips; the process was quantitatively measured and characterized both experimentally and via quantum-based simulations. Our results show that the bond can be ruptured either by applying an attractive force of ~150 pN or by a repulsive force of ~220 pN with a significant contribution of shear forces, accompanied by changes of the spin state of the system. Our combined experimental and computational studies provide a deeper understanding of the chemical bond breaking process.

SUBMITTER: Chen P

PROVIDER: S-EPMC8463581 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Breaking a dative bond with mechanical forces.

Chen Pengcheng P Fan Dingxin D Zhang Yunlong Y Selloni Annabella A Carter Emily A EA Arnold Craig B CB Dankworth David C DC Rucker Steven P SP Chelikowsky James R JR Yao Nan N

Nature communications 20210924 1

Bond breaking and forming are essential components of chemical reactions. Recently, the structure and formation of covalent bonds in single molecules have been studied by non-contact atomic force microscopy (AFM). Here, we report the details of a single dative bond breaking process using non-contact AFM. The dative bond between carbon monoxide and ferrous phthalocyanine was ruptured via mechanical forces applied by atomic force microscope tips; the process was quantitatively measured and charact ...[more]

PMID: 34561452

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