Multi-component molecular conductors with supramolecular assembly based on ET radical cation salts with (NO3)− anion

Methyl-ethylenedithio-tetrathiafulvalene (Me-EDT-TTF (1) and dimethyl-ethylenedithio-tetrathiafulvalene (DM-EDT-TTF (2) are valuable precursors for chiral molecular conductors, which are generally obtained by electrocrystallization in the presence of various counter-ions. The number of the stereogenic centers, their relative location on the molecule, the nature of the counter-ion and the electrocrystallization conditions play a paramount role in the crystal structures and conducting properties of the resulting materials. Here, we report the preparation and detailed structural characterization of the following series of radical cation salts: (i) mixed valence (1)2AsF6 as racemic, and (S) and (R) enantiomers; (ii) [(S)-1]AsF6·C4H8O and [(R)-1]AsF6·C4H8O where a strong dimerization of the donors is observed; (iii) (1)I3 and (2)I3 as racemic and enantiopure forms and (iv) [(meso)-2]PF6 and [(meso)-2]XO4 (X = Cl, Re), based on the new donor (meso)-2. In the latter, the two methyl substituents necessarily adopt axial and equatorial conformations, thus leading to a completely different packing of the donors when compared to the chiral form (S,S)/(R,R) of 2 in its radical cation salts. Single crystal resistivity measurements, complemented by thermoelectric power measurements in the case of (1)2AsF6, suggest quasi-metallic conductivity for the latter in the high temperature regime, with σRT ≈ 1–10 S cm–1, while semiconducting behavior is observed for the (meso)-2 based salts.

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Chiral Conducting Me-EDT-TTF and Et-EDT-TTF-Based Radical Cation Salts with the Perchlorate Anion

Crystals ◽

10.3390/cryst10111069 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1069

Author(s):

Nabil Mroweh ◽

Pascale Auban-Senzier ◽

Nicolas Vanthuyne ◽

Elsa B. Lopes ◽

Manuel Almeida ◽

...

Keyword(s):

Radical Cation ◽

Structural Changes ◽

Crystal Packing ◽

Tight Binding ◽

Molecular Conductors ◽

Temperature Conductivity ◽

Room Temperature Conductivity ◽

Crystalline Materials ◽

Metallic Conductivity ◽

Radical Cation Salts

Introduction of chirality in the field of molecular conductors has received increasing interest in recent years in the frame of modulation of the crystal packing, and hence conducting properties, with the number of stereogenic centers and absolute configuration, e.g., racemic or enantiopure forms. Here, we describe the preparation by electrocrystallization of chiral radical cation salts, based on the donors methyl-ethylenedithio-tetrathiafulvalene (Me-EDT-TTF) 1 and ethyl-ethylenedithio-tetrathiafulvalene (Et-EDT-TTF) 2 containing one stereogenic center, with the perchlorate anion. Donor 1 provided the series of crystalline materials [(rac)-1]ClO4, [(S)-1]2ClO4 and [(R)-1]2ClO4, while for donor 2 only the 1:1 salts [(rac)-2]ClO4 and [(R)-2]ClO4 could be prepared as suitable single crystals for X-ray analysis. The enantiopure salts of 1 show β-type packing and metallic conductivity in the high temperature regime, with room temperature conductivity values of 5–10 S cm−1, whereas compound [(rac)-2]ClO4 is a very poor semiconductor. Tight-binding extended Hückel band structure calculations support the metallic conductivity of the enantiopure salts of 1 and suggest that small structural changes, possibly induced by thermal contraction or pressure, could lead to a pseudo-elliptic closed Fermi surface, typical for a 2D metal.

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Exploitation of the photochromic nitroprusside anion [ FeNO(CN)5]2-as counterion for constructing molecular conductors: The first radical cation salts based on BDH-TTP and the amide functionalized derivatives of EDT-TTF

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2004114112 ◽

2004 ◽

Vol 114 ◽

pp. 481-485 ◽

Cited By ~ 3

Author(s):

R. Shibaeva ◽

S. Khasanov ◽

L. Zorina ◽

S. Simonov ◽

I. Shevyakova ◽

...

Keyword(s):

Radical Cation ◽

Molecular Conductors ◽

Radical Cation Salts ◽

Derivatives Of ◽

Nitroprusside Anion

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New Electroconducting Radical Cation Salts Based on BEDT-TTF with 8,8’-Dibromo Cobalt Bis(Dicarbollide) Anion

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.54.331 ◽

2008 ◽

Vol 54 ◽

pp. 331-336 ◽

Cited By ~ 4

Author(s):

Olga Kazheva ◽

Grigorii Alexandrov ◽

Andrey Kravchenko ◽

Vladimir Starodub ◽

Irina Lobanova ◽

...

Keyword(s):

Crystal Structure ◽

Electrical Conductivity ◽

Crystal Structures ◽

Radical Cation ◽

Molecular Conductors ◽

Electrical Conductivities ◽

Radical Cation Salts

New molecular conductors on the base of 8,8’-dibromo cobalt bis(dicarbollide) anion, (BEDT-TTF)2[8,8’-Br2-3,3’-Co(1,2-C2B9H10)2] (1), and (BEDT-TTF)[8,8’-Br2-3,3’-Co(1,2-C2B9H10)2] (2) were synthesized and their crystal structures and electrical conductivities were determined. Both radical cation salts prepared were found to be semiconductors. The introduction of two bromine atoms in the cobalt bis(dicarbollide) anion produces a strong effect on crystal structure and electrical conductivity of the prepared materials.

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Novel radical cation salts of organic π-donors containing iodine atom(s): the first application of strong intermolecular-I···X-(X = CN, halogen atom) interaction to molecular conductors

Synthetic Metals ◽

10.1016/0379-6779(95)03322-x ◽

1995 ◽

Vol 73 (2) ◽

pp. 117-122 ◽

Cited By ~ 93

Author(s):

Tatsuro Imakubo ◽

Hiroshi Sawa ◽

Reizo Kato

Keyword(s):

Radical Cation ◽

Iodine Atom ◽

Halogen Atom ◽

Molecular Conductors ◽

Atom Interaction ◽

Radical Cation Salts

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Peculiarities of the synthesis, structure and properties of ET radical cation salts prepared in the presence of the rare-earth metal complex anions

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2004114124 ◽

2004 ◽

Vol 114 ◽

pp. 527-528 ◽

Cited By ~ 3

Author(s):

N. D. Kushch ◽

A. V. Kazakova ◽

L. I. Buravov ◽

A. N. Chekhlov ◽

E. B. Yagubskii

Keyword(s):

Rare Earth ◽

Metal Complex ◽

Radical Cation ◽

Rare Earth Metal ◽

Earth Metal ◽

Structure And Properties ◽

Rare Earth Metal Complex ◽

Radical Cation Salts ◽

Complex Anions ◽

The Rare Earth

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New Radical Cation Salts Based on BDH-TTP Donor: Two Stable Molecular Metals with a Magnetic [ReF6]2− Anion and a Semiconductor with a [ReO4]− Anion

Magnetochemistry ◽

10.3390/magnetochemistry7040054 ◽

2021 ◽

Vol 7 (4) ◽

pp. 54

Author(s):

Nataliya D. Kushch ◽

Gennady V. Shilov ◽

Lev I. Buravov ◽

Eduard B. Yagubskii ◽

Vladimir N. Zverev ◽

...

Keyword(s):

Radical Cation ◽

Low Temperatures ◽

Ac Susceptibility ◽

Slow Relaxation ◽

Organic Radical ◽

Inorganic Anion ◽

Distinctive Features ◽

Metallic Character ◽

Radical Cation Salts ◽

Partial Population

Three radical cation salts of BDH-TTP with the paramagnetic [ReF6]2− and diamagnetic [ReO4]− anions have been synthesized: κ-(BDH-TTP)4ReF6 (1), κ-(BDH-TTP)4ReF6·4.8H2O (2) and pseudo-κ″-(BDH-TTP)3(ReO4)2 (3). The crystal and band structures, as well as the conducting properties of the salts, have been studied. The structures of the three salts are layered and characterized by alternating κ-(1, 2) and κ″-(3) type organic radical cation layers with inorganic anion sheets. Similar to other κ-salts, the conducting layers in the crystals of 1 and 2 are formed by BDH-TTP dimers. The partial population of positions of Re atoms and disorder in the anionic layers of 1–3 are their distinctive features. Compounds 1 and 2 show the metallic character of conductivity down to low temperatures, while 3 is a semiconductor. The ac susceptibility of crystals 1 was investigated in order to test the possible slow relaxation of magnetization associated with the [ReF6]2− anion.

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