3 research outputs found
Molecular dynamics of C-60 in superconducting Na2CsC60
No full textWe have measured the low-energy inelastic neutron scattering spectra of
superconducting Na2CsC60 in the temperature range 100-350 K.
Well-defined librational peaks are observed at 2.7(1) meV; their
position and width are temperature independent. They survive well above
the order-disorder transition at 299 K. A quasielastic feature with a
width 1.03(6) meV at an average scattering vector of 1.09 Angstrom(-1)
is observed at 350 K, arising from diffusive motion of the C-60(3-)
ions. Evidence is found for influence of the Na+ ions on the rotational motion of the C-60(3-) ions
Hyperfine Interactions 104 (1997) 269--274 269 A
No full textIntroduction Ferritin comprises of a proteic structure of outer diameter 13 nm that is able to host a variety of mineral cores in its inner 8 nm cavity [1]. In natural ferritin, the core consists of iron oxide hydroxide, similar to the ferrihydrite mineral, 5Fe 2 O 3 9H 2 O with the Fe 3+ ions present in the high spin configuration, S = 5 2 [2]; the iron spins order antiferromagnetically below 240 K [3]. In addition, the cores can be artificially reconstituted within the intact apoferritin with control of the particle composition and size. Ferritin has been extensively utilised as a model system in which magnetism on the nanometer scale can be studied [4]. Each core contains up to a maximum of 4500 iron ions, with an average core size of N # 2500 found in natural ferritin. A net magnetic moment, c , results from uncompensated iron spins at the surface of the core [5]. This is of the order of N , giving c # 250 B .AseriesofM ossbauer [6] and magnetisation [4,7] measurement
