• d –( EDT-TTF-CONMe 2 ) 2 X ( AsF 6 – , Cl – , Br – , ReO 4 – ,...):

1. UMR 6200 from functional (D/A of H-bonds) p-donors with no symmetry to current issues in Motts physics Patrick Batail • d–(EDT-TTF-CONMe2)2X (AsF6–, Cl–, Br–, ReO4–,...): a non-dimerized, 1/4-filled band system is a Mott insulator • (EDT-TTF-CONH2)6[Re6Se8(CN)6], molecular movements and Mott localization in a metallic molecular Kagomé (S = ½) Sixth International Symposiumon Crystalline Organic Metals,Superconductors, and Ferromagnets September 11-16, 2005Key West, FloridaWyndham Casa Marina Resort

2. centers of symmetry allow for any amount of dimerization • the molecule is symmetric • 3.63 Å 2to1 • 3.66 Å 2 molecules per unit along chain Bechgaard and Fabre salts

3. transverse effect materials chemistry: functionalization of p-donor core in order to promote a transverse effect ( in a direction perpendicular to pp-pp overlap) added value: p-donors with no symmetry, eventually chirals

4. functional p-donors (D/A of H-bonds) with no symmetry J. Mater. Chem.1999, 9, 2373 Chem. Rev.2004, 104, 5379 Avarvari et al. J. Am. Chem. Soc.2005, 127, 5748

5. d–(EDT-TTF-CONMe2)2X (AsF6–, Cl–, ReO4–,...) genuine quarter-filled band Mott insulators C1 symmetry Heuzé, Baudron, Allain, Fourmigué, Batail, Coulon, Clérac, Canadell, Auban, Jérome

6. P21/c apply glide plane [±c/2]

7. glide plane imposes by the C1 Molecular Symmetry P21/c @ 150 K t t glide planes @ 1/4 and 3/4 along b glide plane imposes stack uniformity non dimerized, 2 molecules, 1 hole per unit along chain: band is ¼-filled with holes t = + 71 meV despite criss-cross overlap:

8. non-dimerized “ 1/4-filled ” systems in one-dimension Seo, Hotta and Fukuyama Chem. Rev.2004, 104, 5005 Giamarchi Chem. Rev.2004, 104, 5037

9. for systems of strongly correlated electrons in 1D the electronic system can transfer momemtum to the lattice and get it back the umklapp terms can be viewed as the action of the periodic potentiel due to the lattice on the density of electrons umklapps do not conserve momentum: lead to a finite resistivity

10. for systems of strongly correlated electrons in 1D (DI-DCNQI)2Ag: Kanoda, Seo Charge Ordering: Seo et al. Chem. Rev.2004, 104, 5005 Giamarchi Chem. Rev.2004, 104, 5037 Kanoda et al. Chem. Rev.2004, 104, 5635 Dressel et al. Chem. Rev.2004, 104, 5655 Coulon et al. Chem. Rev.2004, 104, 5689

11. Mott insulator: the underlying mechanism for fermions localization can only come from the quarter-filling umklapp Mott gap mostly controlled by the on-site and nearest neighbor interactions Auban-Senzier Jérome Adv. Mater. 15, 1251-1254 (2003)

12. interplay of electronic instability, molecular motion, Mott localization in a metallic molecular Kagome Baudron, Batail, Coulon, Clérac, Canadell, Laukhin, Melzi, Wzietek, Jérome, Auban-Senzier, Ravy J. Am. Chem. Soc.127(33), 11785-11797 (2005)

13. 0.3 V/SCE EDT-TTF-CONH2 vs Re6Se8(CN)6]4—/3—• Heuzé, Fourmigué, Batail et al. J. Mater. Chem.1999, 9, 2373 Chem. Eur. J.1999, 5, 2971 Batail et al. Chem. Rev.2001, 101, 2037 redox active, luminescent, hexanuclear, molecular chalcogenide cluster Sasaki, Fedorov et al. Chem. Lett.1999, 1121 S. Baudron, P. Batail et al. J. Am. Chem. Soc.127(33), 11785-11797 (2005)

14. 6 EDT-TTF-CONH2+ Re6Se8(CN)6]4–/3–• – 3

15. – R3 a = 15.019(2) Å a = 61.465(2)° V = 2474.5 Å3 Kagome net S = 1/2

16. (EDT-TTF-CONH2)6(4-)+[Re6Se8(CN)6](4-)– bHOMO-HOMO intradimer 0.7062 eV interdimer 0.1375 eV Canadell

17. (EDT-TTF-CONH2)6(4-r)+[Re6Se8(CN)6](4-r)– 2D NO OVERLAP Canadell

18. single crystal esr H H Coulon, Clérac

19. analysis of hybrid resonance g(T) = x(T) gorg + (1-x(T))ginorg gorg = 2.0090 and ginorg = 2.5* x(T) = corg(T)/( corg(T)+ cinorg(T)) density of paramagnetic inorganic objects: n(T) = T cinorg(T)/0.375 ~ 1% of [Re6Se8(CN)6]3 *Larina, Ikorskii, Vasenin, Anufrienko, Naumov, Ostanina, Fedorov Russ. Journ. Coord. Chem., 2002, 28, 554

20. number n(T) of [Re6Se8(CN)6]3 clusters per mole

21. carriers at room temperature: [Re6Se8(CN)6(4)–]0.98 24 e– cluster, diamagnetic [Re6Se8CN)63(•)–]0.02 23 e–, Jahn-Teller active, paramagnetic S = ½ cluster (EDT-TTF-CONH2)6(3.92)+ (EDT-TTF-CONH2)6(4)+[Re6Se8(CN)6](4)– below transition (EDT-TTF-CONH2)2(1)+ (EDT-TTF-CONH2)2(1)+ (EDT-TTF-CONH2)2(2)+

22. charge localization coupled to molecular motion triclinic structure @ 100 K [EDT-TTF-CONH2+•]2 [EDT-TTF-CONH2]2+•

23. (EDT-TTF-CONH2)6(4-r)+[Re6Se8(CN)6](4-r)– F (r = 1) F (r = 0) Canadell

24. Canadell

25. Mott localization below 200 K T(K) 100 300 mixed valence, slipped 2+ 2+ fully oxidized, more ecliped 2+ 2+

26. ESR conductivity s = 8 S cm-1

27. Vladimir Laukhin

28. Vladimir Laukhin

29. SQUID data ESR data Coulon, Clérac

30. 1H spin-lattice relaxation rate, 1/T1 measured at different magnetic fields on one single crystral Roberto Melzi, Pawel Wzietek, Denis Jérome

31. relaxation due to hyperfine coupling electrons/nuclear spins motion-induced relaxation strong 1D AF fluctuations (1/T1 independent of T)

32. Fermions with spins Single particle Spinon Holon a single-particle excitation is converted into an excitation that contains only charge degrees of freedom (holon) and spin degrees of freedom (spinon) because only collective excitations exist, a single excitation has to split into • a collective excitation carrying charge (like a sound wave) and • a collective excitation carrying spins (like a spin wave) Giamarchi Chem Rev 2004

33. charge and spin degrees of freedom are decoupled: sizeable electron-electron interactions 100 K 300 K no gap in spin susceptibility below 100 K Canadell large cspin at low T 900 K

34. Conclusion: Mott localization M-I transition coupled to phase transition molecular motion (softness of interfacial H-bond interactions) J. Am. Chem. Soc.127(33), 11785-11797 (2005)

35. UMR 6200 Stéphane BAUDRON, Karine HEUZE, Lika ZORINA Cécile MEZIERE, Marc FOURMIGUE Enric CANADELL Vladimir LAUKHIN ICMAB-CSIC Barcelona Rodolphe CLERAC Claude COULON CRPP-CNRS Talence Pascale AUBAN-SENZIER Denis JEROME Roberto MELZI Pawel WZIETEK Sylvain RAVY LPS Orsay