Orientational disorder of C[sub 60] in Li[sub 2]CsC[sub 60]

Journal Article · Fri May 27 00:00:00 EDT 1994 · Science (Washington, D.C.); (United States)

DOI:https://doi.org/10.1126/science.264.5163.1294· OSTI ID:7243657

Hirosawa, Ichiro; Mizuki, Junichiro; Tanigaki, Katsumi ^[1]; Prassides, K; Gevaet, M; Lappas, A ^[2]; Cockcroft, J K ^[3]

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1. Fundamental Research Labs., Tsukuba (Japan)
2. Univ. of Sussex, Brighton (United Kingdom)
3. Birkbeck College, London (United Kingdom)

The x-ray diffraction of the nonsuperconducting ternary fulleride Li[sub 2]CsC[sub 60] reveals at room temperature a face-centered-cubic (Fm3m) disordered structure that persists to a temperature of 13 Kelvin. The crystal structure is best modeled as containing quasispherical [radius of 3.556(4) angstroms] C[sup 3[minus]][sub 60] ions, in sharp contrast to their orientational state in superconducting face-centered-cubic K[sub 3]C[sub 60] (merohedral disorder) and primitive cubic Na[sub 2]CsC[sub 60] (orientational disorder). The orientational disorder of the carbon atoms on the C[sup 3[minus]][sub 60] sphere was analyzed with symmetry-adapted spherical-harmonic functions. Excess atomic density is evident in the (111) directions, indicating strong bonding Li[sup +]-C interactions, not encountered before in any of the superconducting alkali fullerides. The intercalate-carbon interactions and the orientational state of the fullerenes have evidently affected the superconducting pair-binding mechanism in this material.

• OSTI ID: 7243657
• Journal Information: Science (Washington, D.C.); (United States), Vol. 264:5163; ISSN 0036-8075
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CESIUM COMPOUNDS
CRYSTAL STRUCTURE
FULLERENES
LITHIUM COMPOUNDS
SUPERCONDUCTORS
ALKALI METAL COMPOUNDS
CARBON
ELEMENTS
NONMETALS
360602* - Other Materials- Structure & Phase Studies
400201 - Chemical & Physicochemical Properties