sup 13 C double bond sup 13 C isotope effect for Tc and consequence regarding the superconducting pairing mechanism in. kappa. -(ET) sub 2 X superconductors

Journal Article · Wed Aug 05 04:00:00 EDT 1992 · Inorganic Chemistry; (United States)

DOI:https://doi.org/10.1021/ic00042a004· OSTI ID:7241233

Carlson, K D; Kini, A M; Klemm, R A; Wang, H H; Williams, J M; Geiser, U; Kumar, S K; Ferraro, J R; Lykke, K R; Wurz, P; Fleshler, S; Dudek, J D; Eastman, N L; Mobley, P R; Seaman, J M; Sutin, J D.B.; Yaconi, G A ^[1]; Parker, D H ^[2]; Stout, P ^[3]

---

1. Argonne National Lab., IL (United States)
2. Univ. of California, Irvine (United States) Argonne National Lab., IL (United States)
3. Bio-Rad, Cambridge, MA (United States)

In this communication, the authors report the first determination of the isotope effect for {sup 13}C substitution in the central C {double bond} C atoms of ET (ET is bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF)) in the organic superconductors {kappa}-(ET){sub 2}Cu(N(CN){sub 2})Br ({Tc} = 11.6 {plus minus} 0.05 K, diamagnetic onset) and {kappa}-(ET){sub 2}Cu(NCS){sub 2} ({Tc} = 9.8 {plus minus} 0.3 K, diamagnetic onset). These materials, presently the highest-{Tc} electron-donor-based, ambient-pressure organic superconductors, are much better materials for tests of the isotope effect for ET-based superconductors than pressurized {beta}-(ET){sub 2}I{sub 3} because {Tc} is easily reproducible from sample-to-sample at ambient pressure. These results show that the central C {double bond} C stretching motion is not a dominant exchange mechanism over conventional BCS-type phonon exchange for superconducting pairing in {kappa}-(ET){sub 2}Cu(Nu(CN){sub 2})Br and {kappa}-(ET){sub 2}Cu(NCS){sub 2}.

• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 7241233
• Journal Information: Inorganic Chemistry; (United States), Journal Name: Inorganic Chemistry; (United States) Vol. 31:16; ISSN 0020-1669; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360607 -- Other Materials-- Superconducting Properties-- (1992-)
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
AMINES
BEDT-TTF
CARBON 13
CARBON ISOTOPES
CHEMICAL BONDS
COPPER COMPOUNDS
DATA
DOUBLE BONDS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
EVEN-ODD NUCLEI
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
HIGH-TC SUPERCONDUCTORS
INFORMATION
ISOTOPE EFFECTS
ISOTOPES
LIGHT NUCLEI
NUCLEI
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANIC SUPERCONDUCTORS
PHYSICAL PROPERTIES
STABLE ISOTOPES
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS