scholarly journals Face-to-Face Dimeric Tetrathiafulvalenes and Their Cation Radical and Dication Species as Models of Mixed Valence and π-Dimer States

2012 ◽  
Vol 85 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Masashi Hasegawa ◽  
Kota Daigoku ◽  
Kenro Hashimoto ◽  
Hiroyuki Nishikawa ◽  
Masahiko Iyoda
Keyword(s):  
Mixed Valence ◽  
Cation Radical ◽  
Face To Face

scholarly journals Star-shaped tetrathiafulvalene oligomers towards the construction of conducting supramolecular assembly

2015 ◽  
Vol 11 ◽  
pp. 1596-1613 ◽  
Author(s):  
Masahiko Iyoda ◽  
Masashi Hasegawa
Keyword(s):  
Mixed Valence ◽  
Supramolecular Assembly ◽  
Radical Cations ◽  
Supramolecular Assemblies ◽  
Supramolecular Structures ◽  
Oxidation States ◽  
Face To Face ◽  
Redox Active ◽  
Nanophase Separation ◽  
Self Organizing

The construction of redox-active supramolecular assemblies based on star-shaped and radially expanded tetrathiafulvalene (TTF) oligomers with divergent and extended conjugation is summarized. Star-shaped TTF oligomers easily self-aggregate with a nanophase separation to produce supramolecular structures, and their TTF units stack face-to-face to form columnar structures using the fastener effect. Based on redox-active self-organizing supramolecular structures, conducting nanoobjects are constructed by doping of TTF oligomers with oxidants after the formation of such nanostructures. Although radical cations derived from TTF oligomers strongly interact in solution to produce a mixed-valence dimer and π-dimer, it seems to be difficult to produce nanoobjects of radical cations different from those of neutral TTF oligomers. In some cases, however, radical cations form nanostructured fibers and rods by controlling the supramolecular assembly, oxidation states, and counter anions employed.

The 1,2,3,5-ditelluradiazolyl [HCN2Te2] species. Theoretical characterizations of the cation, radical, and radical dimers

1996 ◽  
Vol 74 (6) ◽  
pp. 810-818 ◽  
Author(s):  
William M. Davis ◽  
John D. Goddard
Keyword(s):  
Ab Initio ◽  
Electron Correlation ◽  
Cation Radical ◽  
Building Blocks ◽  
Molecular Conductors ◽  
Face To Face ◽  
Hartree Fock ◽  
Symmetry Constraints ◽  
Moller Plesset ◽  
Low Dimensional

Dithia- and diselena-diazolyl radicals (HCN2E2 E = S, Se) and dimers are important building blocks in the design of low-dimensional molecular conductors. Research on the tellurium-based analogues is much rarer. This work reports the molecular and electronic structures of the cation, radical, and radical dimers of 1,2,3,5-ditelluradiazolyl using ab initio theory including electron correlation by Møller–Plesset perturbation theory up to partial fourth order (MP4SDQ). A face-to-face C2v dimer is predicted to be bound with respect to two radicals by approximately 18 kcal/mol. A C2h, dimer also has been studied and is ca. 2 kcal/mol less stable than the C2v conformer. Relaxing symmetry constraints on the dimers led to more energetically stable structures at the Hartree–Fock level but the C2v structure remains the most stable at a level of theory including electron correlation effects. The results for the Te compounds along with our earlier research on the S and Se analogues provide predictions for the geometries, vibrational frequencies, and ionization potentials for the Te species to assist in future experiments. Key words: tellurium, ab initio, ditelluradiazolyl, dimers, binding.

Cation radical salts of the tetrathiafulvalene series : fast mixed valence detection by thin layer cyclic voltammetry

1993 ◽  
Vol 56 (1) ◽  
pp. 2359-2363 ◽  
Author(s):  
R. Carlier ◽  
A. Tallec ◽  
P. Frere ◽  
M. Salle ◽  
M. Jubault ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Thin Layer ◽  
Mixed Valence ◽  
Cation Radical

A parametric two-mode vibronic model of a dimeric mixed-valence cell for molecular quantum cellular automata and computational ab initio verification

2020 ◽  
Vol 22 (44) ◽  
pp. 25982-25999
Author(s):  
Andrew Palii ◽  
Sergey Aldoshin ◽  
Shmuel Zilberg ◽  
Boris Tsukerblat
Keyword(s):  
Cellular Automata ◽  
Ab Initio ◽  
Mixed Valence ◽  
Cation Radical ◽  
Quantum Cellular Automata ◽  
Parametric Approach

Here we propose a two-mode vibronic model of a molecular cell for quantum cellular automata. The interconnection between the parametric approach and ab initio evaluations for the cation-radical of tetramethyleneethane molecule is established.

Syntheses and crystal structures of two heterometallic iodoplumbates containing mixed-valence copper(I/II)

2017 ◽  
Vol 73 (12) ◽  
pp. 1098-1103 ◽  
Author(s):  
Le-Qing Fan ◽  
Xiao-Tong Zhu
Keyword(s):  
Mixed Valence ◽  
Three Dimensional ◽  
Stacking Interactions ◽  
Compound I ◽  
One Dimensional ◽  
Face To Face ◽  
Hydrogen Bonding Interactions ◽  
Compound Ii ◽  
Solvothermal Conditions ◽  
Phenanthroline Ligands

Mixed-valence copper(I/II) atoms have been introduced successfully into a Pb/I skeleton to obtain two heterometallic iodoplumbates, namely poly[bis(tetra-n-butylammonium) [bis(μ3-dimethyldithiocarbamato)dodeca-μ3-iodido-hexa-μ2-iodido-tetracopper(I)copper(II)hexalead(II)]], {(C16H36N)2[Cu4 ICuIIPb6(C3H6NS2)2I18]} n , (I), and poly[[μ3-iodido-tri-μ2-iodido-iodido[bis(1,10-phenanthroline)copper(I)]copper(I)copper(II)lead(II)] hemiiodine], {[CuICuIIPbI5(C12H8N2)2]·0.5I2} n , (II), under solution and solvothermal conditions, respectively. Compound (I) contains two-dimensional anionic layers, which are built upon the linkages of CuII(S2CNMe2)2 units and one-dimensional anionic Pb/I/CuI chains. Tetra-n-butylammonium cations are located between the anionic layers and connected to them via C—H...I hydrogen-bonding interactions. Compound (II) exhibits a one-dimensional neutral structure, which is composed of [PbI5] square pyramids, [CuII4] tetrahedra and [CuIIN4I] trigonal bipyramids. Face-to-face aromatic π–π stacking interactions between adjacent 1,10-phenanthroline ligands stabilize the structure and assemble compound (II) into a three-dimensional supramolecular structure. I2 molecules lie in the voids of the structure.

Mixed-Valence, Layered, Cation Radical Salts of the Ethane-Bridged Dimeric Tetrathiafulvalene [(EDT-TTF−CH2−)2•+][X-][THF]0.5, X-= FeCl4-, GaCl4-

2000 ◽  
Vol 12 (8) ◽  
pp. 2250-2256 ◽  
Author(s):  
Cécile Mézière ◽  
Marc Fourmigué ◽  
Enric Canadell ◽  
Rodolphe Clérac ◽  
Klaus Bechgaard ◽  
...  
Keyword(s):  
Mixed Valence ◽  
Cation Radical

scholarly journals C—I...NC halogen bonding in two polymorphs of the mixed-valence 2:1 charge-transfer salt (EDT-TTF-I2)2(TCNQF4), with segregatedversusalternated stacks

2014 ◽  
Vol 70 (1) ◽  
pp. 141-148 ◽  
Author(s):  
Julien Lieffrig ◽  
Olivier Jeannin ◽  
Antoine Vacher ◽  
Dominique Lorcy ◽  
Pascale Auban-Senzier ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Solid State ◽  
Mixed Valence ◽  
Halogen Bonding ◽  
Halogen Bonds ◽  
Partial Charge Transfer ◽  
Face To Face ◽  
State Association ◽  
A Charge ◽  
State Organization

Oxidation of diiodoethylenedithiotetrathiafulvalene (EDT-TTF-I2), C8H4I2S6, with the strong oxidizer tetrafluorotetracyanoquinodimethane (TCNQF4), C12F4N4, affords, depending on the crystallization solvent, two polymorphs of the 2:1 charge-transfer salt (EDT-TTF-I2)2(TCNQF4), represented asD2A. In both salts, the TCNQF4is reduced to the radical anion state, and is associated through short C—I...NC halogen bonds to two EDT-TTF-I2molecules. The two polymorphs differ in the solid-state association of these trimericD–A–Dmotifs. In polymorph (I) the trimeric motif is located on an inversion centre, and hence both EDT-TTF-I2molecules have +0.5 charge. Together with segregation of the TTF and TCNQ derivatives into stacks, this leads to a charge-transfer salt with high conductivity. In polymorph (II) two crystallographically independent EDT-TTF-I2molecules bear different charges, close to 0 and +1, as deduced from an established correlation between intramolecular bond lengths and charge. Overlap interactions between the halogen-bondedD0–A^{{-}{\bullet}}–D^{{+}{\bullet}} motifs give rise, in a perpendicular direction, to diamagneticA22−andD0–D22+–D0entities, where the radical species are paired into the bonding combination of respectively the acceptor LUMOs and donor HOMOs. The strikingly different solid-state organization of the halogen-bondedD–A–Dmotifs provides an illustrative example of two modes of face-to-face interaction between π-type radicals, into either delocalized, uniform chains with partial charge transfer and conducting behaviour, or localized association of radicals into face-to-faceA22−andD22+dyads.

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