AI Article Synopsis
- The (S,S,S,S) and (R,R,R,R) enantiomers of TM-BEDT-TTF have been found to adopt an equatorial conformation in solid-state structures as confirmed by single-crystal X-ray analyses.
- Theoretical calculations suggest that the axial conformer is more stable in gas phase than the equatorial conformer, providing insights into their UV-vis and circular dichroism properties.
- Electrocrystallization produced a series of radical cation salts with triiodide anions, revealing that while organized dimers facilitate interactions among donors, the racemic mixture shows lower conductivity and higher activation energy due to structural disorder.
Article Abstract
The (S,S,S,S) and (R,R,R,R) enantiomers of tetramethyl-bis(ethylenedithio)-tetrathiafulvalene (TM-BEDT-TTF) show equatorial conformation for the four methyl groups in the solid state, according to the single-crystal X-ray analyses. Theoretical calculations at the Density Functional Theory (DFT) and time-dependent (TD) DFT levels indicate higher gas phase stability for the axial conformer than the equatorial one by 1.25 kcal ∙ mole⁻¹ and allow the assignment of the UV-vis and circular dichroism transitions. A complete series of radical cation salts of 1:1 stoichiometry with the triiodide anion I₃⁻ was obtained by electrocrystallization of both enantiopure and racemic forms of the donor. In the packing the donors are organized in dimers that further interact through S ∙ ∙ ∙ S intermolecular contacts and the triiodide anions lie parallel to pairs of oxidized donors. The conductivity of the racemate, which adopts the same, but disordered, structural type, is considerably lower, with much higher activation energy.
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Article Synopsis
- The (S,S,S,S) and (R,R,R,R) enantiomers of TM-BEDT-TTF have been found to adopt an equatorial conformation in solid-state structures as confirmed by single-crystal X-ray analyses.
- Theoretical calculations suggest that the axial conformer is more stable in gas phase than the equatorial conformer, providing insights into their UV-vis and circular dichroism properties.
- Electrocrystallization produced a series of radical cation salts with triiodide anions, revealing that while organized dimers facilitate interactions among donors, the racemic mixture shows lower conductivity and higher activation energy due to structural disorder.
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