On‐Surface Synthesis of Ethynylene‐Bridged Anthracene Polymers

Abstract

Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.org/10.

Tailoring π-conjugation and vibrational modes to steer on-surface synthesis of pentalene-bridged ladder polymers

“…Following this chemical strategy, we report the synthesis and detailed atomistic characterization by a comprehensive scanning tunneling microscopy (STM) and non-contact atomic force microscopy (nc-AFM) supported by density functional theory (DFT) study of the on-surface reactions of two distinct molecular precursors, 4BrBiA [10,10′-bis(dibromomethylene)-10 H ,10′ H -9,9′-bianthracenylidene] and 4BrAn [9,10-bis(dibromomethylene)-9,10-dihydroanthracene]. The precursors are endowed with = CBr 2 functionalities to allow homocoupling 23 , 27 . The deposition of 4BrAn and 4BrBiA on Au(111) and subsequent annealing at 500 K results in the formation of anthracene ( 1 , Fig.…”

“…1 a) and bisanthene ( 2 , Fig. 1b ) polymers, respectively 23 , 27 . Both polymers exhibit repeating moieties linked by linear bridges, but with distinct π-conjugation.…”

“…Both polymers exhibit repeating moieties linked by linear bridges, but with distinct π-conjugation. While the anthracene polymer adopts aromatic ethynylene π-conjugation character 23 , the bisanthene polymer results in the promotion of the quinoid cumulene-like character 27 .

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Massively parallel quantum chemical density matrix renormalization group method

“…It is a representative of π ‐conjugated hydrocarbons (linear or quasi linear), a group of molecules frequently studied by means of QC‐DMRG calculations in the C‐atom p z active space 17–19,21,23 . We have recently studied the ground state of the above mentioned defected anthracene tetramer with the QC‐DMRG method since this and similar species often appear as unwanted by‐products during on‐surface synthesis of ethynylene‐bridged anthracene polymers 66 . Depending on the defect, such species may exhibit peculiar electronic structure properties.…”

1D Coordination π–d Conjugated Polymers with Distinct Structures Defined by the Choice of the Transition Metal: Towards a New Class of Antiaromatic Macrocycles

“…Pure organic 1D materials can be obtained through catalyzed CÀCcoupling reactions on surface from halogenated precursors. [7,8] Alternatively,1 D coordination-polymers (CPs) can be isolated through coordination chemistry,the covalent bond formation resulting from on-surface reactions between metal atoms and suitable linker groups. [9][10][11][12][13][14] One major advantage of this approach is the possibility to tune the properties of the wires by changing the nature of the metal and/or the ligand.…”