Points of view for the ferroelectricity in p-conjugated frameworks FROM ORGANIC CONDUCTORS TO CONDUCTING POLYMERS

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I.F. Shchegolev Memorial Volume Common Trends in Synthetic Metals and High-Tc Superconductors. Diary de Physique I December 199656 best in class articles on Organic Conductors, related low dimensional frameworks and High-Tc materials.. Illustrations of this volume audits pertinent to this talk:Structural Aspects of the Bechgaard Salts and Related Compounds J.P. Pouget and S. Ravy Investigations of O

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Points of view for the ferroelectricity in π - conjugated frameworks FROM ORGANIC CONDUCTORS TO CONDUCTING POLYMERS S. Brazovski & N. Kirova CNRS - Orsay, France Ferroelectric Mott-Hubbard stage and charge disproportionation in semi 1d natural conduits. Current solicitations for plastic ferroelectrics. Reality: Existing auxiliary ferroelectricity in an immersed polymer. Desires: electronic ferroelectricity in conjugated changed polyenes. Theory: crisscross edge states in graphene

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I.F. Shchegolev Memorial Volume Common Trends in Synthetic Metals and High-Tc Superconductors. Diary de Physique I December 1996 56 best in class articles on Organic Conductors, related low dimensional frameworks and High-Tc materials. Cases of this volume surveys pertinent to this discussion: Structural Aspects of the Bechgaard Salts and Related Compounds J.P. Pouget and S. Ravy Investigations of Organic Conductors by the Shchegolev Method H.W. Helberg and M. Dressel

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« In the start was the Word, … and without him was not anything made that was made » He laid his fingers on my ears And they were loaded with thundering sound: I heard the music of the circles, The flight of Angels through the skies, The monsters that crawled underneath the ocean, The powerful uprush of the vine; … .. 'Rise, prophet, rise, and listen, and see, And let my works be seen and listened' The Profet. Vrubel representation to verses by Pushkin

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His first production and the principal audit: I.F.Shchegolev Signal/clamor proportion of NMR-regenerative locator (1958). I.F.Shchegolev Investigation of electron structure of metals by NMR-procedure (1962). Something exceptional that the authors of Synthetic Metals were originating from the NMR (Heeger, Jerome, Schegolev). The same for the later comers and for the today center (Berthier and Coulon, Clark and Brown, Takahashi and Kanoda) – unless another source : X-beam (Shibaeva, Comes and Pouget, Kagoshima). NMR as a typical instrument and thus an extension amongst material science and science as the embodiment of our science? To be sure, a destiny is heading to the future predetermination, unanticipated yet: Yu.S.Karimov, I.F.Shchegolev Magnetic properties of ferrocene polymers (1962). what's more, now solidly on the way: E.B.Yagubskii, M.L.Chidekel, I.F.Shchegolev, L.I.Buravov, R.B.Lubovskii, V.B.Stryukov Investigation in potential natural superconductors field. I. Painting edifices with 7,7,8,8-tetracyanquinodimethane ( 1968 ).

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Moving to the subject: Shchegolev way of peculiar dielectric susceptibilities. "You have been searching for superconductors and found the superdielectric" - Peotr L. Kapitza remark to the early revelation of the Schegolev amass. L.I.Buravov, M.L.Khidekel, I.F.Shchegolev, E.B.Yagubskii (1970) Superconductivity and dielectric consistent of profoundly conductive buildings of TCQM And then spread over the group :

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Microwave conductivity and dieiectric steady of tetramethyltetrathiafulvalene salts [(TMTTF)2X, X-SCN, Re04, SbF6 H. H. S. Javadi, R. Laversanne, and A. J. Epstein Phys. Rev. B (1988) "Microwave estimations were performed utilizing a depression irritation system [15] which has been an effective apparatus in prior investigations of metal-protector moves, Peierls holes, CDW and turn thickness waves (SDW's) and their ground-state excitations" … [15] L. Buravov and I. F. Shchegolev, Prib. Tekh. Eksp. 2, 171 (1970) These high-T oddities have been seen likewise by different techniques (C.Coulon et al, mid 80's) yet NOT by X-beams (till only 2009 – J.P. Pouget talk), subsequently the name (off base today) "structure-less transitions", then unexplained and surrendered, and the amnesia till 2000's. In today's review, this is the charge requesting stage move which shows up, amusingly, as a ferro-or hostile to ferro-power (ReO4 or SCN cases)

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FERROELECTRIC MOTT-HUBBARD PHASE and CHARGE DISPROPORTIONATION in QUASI 1D ORGANIC CONDUCTORS Felix Nad, Pierre Monceau, S. Brazovskii - PRL 2001 Stuart Brown et al: NMR gathering of UCLA - PRL 2001 Review : S. B. cond-tangle/0606009 & Springer arrangement 2008 T Earlier hypothesis and exploratory indications on the Charge Ordering: Seo and Fukuyama, Kanoda et al (late 90's) Intrigues for natural transmitters and past: 20 years of age riddle of "structureless" stage moves; revaluation of their essential stage graph exactly at the 20'th commemoration (1980) of the superconductivity disclosure; blend of lost connections in manufactured metals : natural conveyors, conjugated polymers, charge thickness waves. Connection to High-Tc world : late disclosure of charge requesting in cobaltides; high-T hybrid line turns into a genuine move.

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(TMTCF) 2 X, 1980 – Bechgaard, Jerome Black and white: SC-superconductivity AF-AFM = SDW SP-Spin-Peierls LL-Luttinger fluid MI-Mott cover Red line T FE – 2000's transformation: Structurless moves ( Coulon et al 1985 ) = Ferroelectricity ( Monceau et al ) = Charge disproportionation ( Brown et al ) Resolving the riddle of structureless moves: Coulon et every one of the, 1985 Gigantic inconsistency in permitivity of (T) ( Nad et al, Grenoble - Moscow ) Charge Orderin seen by NMR ( Brown - UCLA, Fujiyama - IMS ). Perspectives and understandings: FerroElectric Mott-Hubbard state, blended site/bond 4K F CDW, nonsymmetrically stuck Wigner gem, charge requesting = disproportionation Facility to see Solitons: Purely 1D administration for electrons - T FE 150K is 10 times over 3D electronic moves.

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conterion = dopant X Molecule TMTTF or TMTSF Built-in dimerization of bonds - counterions against each second match of particles ) Spontaneous symmetry breaking – removals of counterions, nonequivqlence of destinations Arrows indicate relocations of particles X. They take after and balance out the electronic charge disproportionation. Collinear bolts – ferroelectricity. Substituting bolts – against ferroelectricity. A solitary stack is spellbound regardless. Real polarization originates from redistribution of electronic thickness, subsequently enhancement of polarizability  by a component of ( ω p/∆ ) 2 ~10 2 giving even a foundation  ~10 3

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COMBINED MOTT - HUBBARD STATE 2 sorts of dimerization  2 meddling hotspots for two-overlay commensurability  2 commitments to the Umklapp association: Site dimerization : H U s =-U s cos 2  (spontaneous) Bond dimerization : H U b =-U b sin 2  (build-in) At nearness of both site and bond sorts H U = - U s cos 2  - U b sin 2  = - Ucos (2 -2) U s 0   0  stage  = "mean relocation of all electrons" shifts from  =0 to  = , henceforth the massive FE polarization. From a solitary stack to a gem: Macroscopic FerroElectric ground state if the same  is decided for all stacks, Anti-FE state if the indication of  substitutes - both cases are watched

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AsF6 SbF6 AsF6 ReO4 PF6 SbF6 ReO4 PF6 SCN ′ - direct scale Dielectric abnormality (T) in (TMTTF) 2 X , after Nad & Monceau Left: at f=1MHz in semi logarithmic scale | Right: at f= 100 kHz in straight scale Anti-FE instance of SCN shows just a wrinkle as it ought to be. Smoothened oddity in PF6 associates with its feeble recurrence scattering - Mabe FE space dividers and shrouded hysteresis ?. Different cases - immaculate mono-space "introductory" FE vulnerability.

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T reliance of the reverse of the genuine part : 1/' at f=100Hz , X=PF 6 ,AsF 6 , SbF 6 ,ReO 4 1/' =C(T-T 0 ) Typically C~10 4/T 0 C < =2C > - correct Landau hypothesis ! entanglement: PF 6 Clear cut fitting of the irregularity in  (T ) to the Curie law prooves the slightest expected instance of the f erroelectric stage. Significantly more inquisitively, it is the ferroelectric adaptation of the Mott-Hubbard state and of the Charge Disproportionation.

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Frequency reliance of fanciful piece of ε Comparison of the ε′′(f) bends at two temperatures close T c : above - 105K and beneath - 97K. Low recurrence bear - just at T<Tc : sticking of FE space dividers ? T-reliance of unwinding time for the primary pinnacle: Critical backing off close T c , Activation law at low T – contact of FE area dividers by charge transporters Landau-Khalatnikov basic unwinding

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Ferroelectricity engraving: Inversion symmetry lifting tried by nonlinear optics. Second consonant era λ ( ω )=1400nm K. Yamamoto et al (2008) α - (ET) 2 I 3 - ought to be a metal, really a corresponded (Mott) encasing, underneath T≈140K it turns into a Wigner Crystal Problem of distinguishing proof of the solidified polarization: through odd optical movement - absence of reversal summetry E 3 may exist just in the event of reversal symmetry breaking And shouldn't something be said about's the metallic condition of the Se sub-family? Can the Charge requesting or even Ferroelectricity be covered up there ?

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parasite intra-atomic modes Mott hole 2 Δ ρ in TMTTF develops just when it is as low as in Br Drude crest – TMTSF is a metal ! Log sizes of recurrence Optical Conductivity () = assimilation The top because of either 2 Δ of sets of crimps generation or E g - optical retention edge (exciton = bound kink+antikink) Notice personality of static (TMTTF case) and fluctuational (TMTSF case) Mott states

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Ferroelectricity is a rising interest in key and connected strong state material science. Dynamic entryway materials and electric RAM in microelectronics, Capacitors in convenient WiFi communicators, Electro-Optical-Acoustic modulators , Electro-Mechanical actuators Transducers and Sensors in restorative imaging. Ask for versatility – polymer-earthenware composites work today yet with powerless reactions – viable ε ~10 0 . Plastic ferrroelectrics are essential in restorative imaging – forming, additionally n

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