Unusual stoichiometry, band structure and band filling in conducting enantiopure radical cation salts of TM-BEDT-TTF showing helical packing of the donors
| Autor: | Naoya Tajima, Flavia Pop, Hiroshi Yamamoto, Enric Canadell, Narcis Avarvari, Daichi Hirobe, Pascale Auban-Senzier, Cécile Mézière, Magali Allain |
|---|---|
| Přispěvatelé: | MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Agence Nationale de la Recherche (France), Centre National de la Recherche Scientifique (France), Université d’Angers, Ministerio de Ciencia, Innovación y Universidades (España), Generalitat de Catalunya, Japan Society for the Promotion of Science, Japan Science and Technology Agency |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Materials science
02 engineering and technology Crystal structure 010402 general chemistry 01 natural sciences Formula unit Materials Chemistry [CHIM]Chemical Sciences Molecular conductor Isostructural Chirality Electronic band structure Polyoxometalate General Chemistry 021001 nanoscience & nanotechnology 0104 chemical sciences 3. Good health Crystallography Enantiopure drug Radical ion Crystal-structure Organic conductors Dirac electron-systems EDT-TTF 0210 nano-technology Single crystal Monoclinic crystal system |
| Zdroj: | Journal of Materials Chemistry C Journal of Materials Chemistry C, Royal Society of Chemistry, 2021, 9 (33), pp.10777-10786. ⟨10.1039/D1TC01112J⟩ Digital.CSIC: Repositorio Institucional del CSIC Consejo Superior de Investigaciones Científicas (CSIC) Digital.CSIC. Repositorio Institucional del CSIC instname |
| ISSN: | 2018-0969 2050-7526 2050-7534 |
| DOI: | 10.1039/D1TC01112J⟩ |
| Popis: | Electrocrystallization of tetramethyl-bis(ethylenedithio)-tetrathiafulvalene (TM-BEDT-TTF) (1) as pure (S,S,S,S) and (R,R,R,R) enantiomers in the presence of (n-Bu4N)2(Mo6O19) and chloroform or bromoform afforded a series of four isostructural enantiopure radical cation salts [(S/R)-1]9(Mo6O19)5·(CHX3)2 (X = Cl, Br) crystallizing in the trigonal non-centrosymmetric space group R32. In the formula unit there are six donors of type A and three donors of type B showing, respectively, (ax, ax, eq, eq) and all-ax conformations (ax = axial, eq = equatorial) of the methyl substituents. The donors form a hexagonal network in the ab plane with a helical twist between them leading to lateral orbital overlap interactions. Electrocrystallization of the racemic donor provided the compound [(rac)-1]2(Mo6O19) which crystallized in the monoclinic system P21/n. Single crystal resistivity measurements show semiconducting behaviour of the enantiopure materials with a relatively high room temperature conductivity of 0.8–1.2 S cm−1, but rather insensitive to applied pressures of up to 2.3 GPa. Analysis of the electronic structure of the conducting solids through extended Hückel tight-binding band structure calculations indicates a Mott insulator behaviour explaining the semiconducting character and suggests that these compounds are valuable candidates for Dirac cone materials. Further insight into the conducting properties is provided by preliminary field effect transistor measurements. This work was supported in France by the National Agency for Research (ANR, Project 15-CE29-0006-01 ChiraMolCo), the CNRS and the University of Angers. Work at Bellaterra (Spain) was supported by the Spanish MICIU through Grant PGC2018-096955-B-C44 and the Severo Ochoa FUNFUTURE (CEX2019-000917-S) Excellence Centre distinction as well as by Generalitat de Catalunya (2017SGR1506). This work was also partially supported in Chiba, Japan by MEXT = JSPJ KAKENHI under Grants No. 16H06346 and 20K03870. Work in Okazaki was supported by Grant-in-Aid for Scientific Research (A) (Grant Number 19H00891) and Grant-in-Aid for Challenging Research (Exploratory) (Grant Number 20K20903) from JSPS as well as PRESTO (Grant Number JPMJPR20L9) from JST. |
| Databáze: | OpenAIRE |
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