scholarly journals Chiral Radical Cation Salts of Me-EDT-TTF and DM-EDT-TTF with Octahedral, Linear and Tetrahedral Monoanions

2021 ◽  
Vol 7 (6) ◽  
pp. 87
Author(s):  
Nabil Mroweh ◽  
Alexandra Bogdan ◽  
Flavia Pop ◽  
Pascale Auban-Senzier ◽  
Nicolas Vanthuyne ◽  
...  
Keyword(s):  
Radical Cation ◽  
Mixed Valence ◽  
Relative Location ◽  
Molecular Conductors ◽  
Resistivity Measurements ◽  
Counter Ions ◽  
Stereogenic Centers ◽  
Radical Cation Salts ◽  
Power Measurements

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.

New low-dimensional molecular conductors based on bis(ethylenedithio)tetrathiafulvalene radical cation salts with octahedral metal complex anion [ReIVCl6]2–

2016 ◽  
Vol 65 (10) ◽  
pp. 2388-2395
Author(s):  
S. S. Khasanov ◽  
A. V. Kazakova ◽  
A. O. Tolstikova ◽  
S. V. Simonov ◽  
E. B. Yagubskii ◽  
...  
Keyword(s):  
Metal Complex ◽  
Radical Cation ◽  
Complex Anion ◽  
Molecular Conductors ◽  
Radical Cation Salts ◽  
Low Dimensional

The First Mixed Valence Radical Cation Salts of BEDT-TTF with the Photochromic Metal Mononitrosyl Complexes [RuNOX5]2− (X=Br, Cl) as Counterions

2002 ◽  
Vol 168 (2) ◽  
pp. 514-523 ◽  
Author(s):  
I.Yu. Shevyakova ◽  
L.V. Zorina ◽  
S.S. Khasanov ◽  
L.I. Buravov ◽  
V.A. Tkacheva ◽  
...  
Keyword(s):  
Radical Cation ◽  
Mixed Valence ◽  
Radical Cation Salts

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

Crystals ◽  
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.

Synthesis and Physical Properties of two Organic Donor Derivatives of 12-Molybdophosphate Anion [PMO12O40] n-: New Examples of Mixed-Valence Organic Donor-Inorganic Acceptor Compounds

1992 ◽  
Vol 247 ◽  
Author(s):  
D. Attanasio ◽  
C. Bellitto ◽  
M. Bonamico ◽  
G. Righini ◽  
G. Staulo
Keyword(s):  
Electrical Conductivity ◽  
Physical Properties ◽  
Radical Cation ◽  
Organic Semiconductors ◽  
Mixed Valence ◽  
Two Dimensional ◽  
Keggin Anion ◽  
Radical Cation Salts ◽  
Mixed Valence Compounds ◽  
Derivatives Of

ABSTRACTTetrathiafulvalene and bis(ethylenedithio)tetrathiaful-valene radical-cation salts of the a-Keggin anion [PMo12O40] have been synthesized and characterized. They both are mixed-valence compounds and contain the paramagnetic anion [PMO12O40] 4-. The former contains irregular TTF ϱ+ chains isolated by the inorganic anions. From the IR spectrum a ϱ=+0.5 is suggested. The latter is two-dimensional, where BEDT-TTF molecules are ionised, ϱ=+0.5, and arranged in irregular chains. They show electrical conductivity typical of organic semiconductors.

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