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Semiconductive 2D arrays of pancake-bonded oligomers of partially charged TCNQ radicals.

ABSTRACT: Multicentre two-electron (mc/2e or 'pancake bonding') bonding between 7,7,8,8-tetra-cyano-quinodi-methane (TCNQ) radical anions was studied on its 14 novel salts with planar organic cations. The formal charges of the TCNQ^δ- moieties are -1/2 and -2/3, and they form mc/2e bonded dimers, trimers and tetramers which are further stacked into extended arrays. Multicentre bonding within these oligomers is characterized by short interplanar separations of 2.9-3.2 Å; distances between the oligomers are larger, typically >3.3 Å. The stacks are laterally connected by C-H⋯N hydrogen bonding, forming 2D arrays. The nature of mc/2e bonding is characterized by structural, magnetic and electrical data. The compounds are found to be semiconductors, and high conductivity [10^-2 (Ω cm)^-1] correlates with short interplanar distances between pancake-bonded oligomers.

SUBMITTER: Molcanov K

PROVIDER: S-EPMC9252159 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Semiconductive 2D arrays of pancake-bonded oligomers of partially charged TCNQ radicals.

Molčanov Krešimir K Milašinović Valentina V Kojić-Prodić Biserka B Maltar-Strmečki Nadica N You Jiangyang J Šantić Ana A Kanižaj Lidija L Stilinović Vladimir V Fotović Luka L

IUCrJ 20220528 Pt 4

Multicentre two-electron (mc/2e or 'pancake bonding') bonding between 7,7,8,8-tetra-cyano-quinodi-methane (TCNQ) radical anions was studied on its 14 novel salts with planar organic cations. The formal charges of the TCNQδ- moieties are -1/2 and -2/3, and they form mc/2e bonded dimers, trimers and tetramers which are further stacked into extended arrays. Multicentre bonding within these oligomers is characterized by short interplanar separations of 2.9-3.2 Å; distances between the oli ...[more]

PMID: 35844480

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