D2hD3d/D5d

1
Distortions of C60 studied by infrared
spectroscopyG. Klupp, F. Borondics, G.
Oszlányi, K. Kamarás, N. M. Nemes, J. E.
Fischer, A. F. Hebard, D. B.
TannerResearch Institute for Solid State
Physics and Optics, P. O. Box 49, Budapest, H
1525, Hungary, email klupp_at_para.chem.elte.huLab
oratory on the Research of the Stucture of
Matter, University of Pennsylvania, Philadelphia,
PA 19104, USADepartment of Physics, University
of Florida, Gainesville, FL 32611, USA
Funding Hungary OTKA T 034198, T 029931
US NSF-INT 9902050
4-
IR(this work) D2h D3d/D5d K4C60 T lt
260-280K T gt 260-280K Rb4C60 T lt 180-220
K T gt 180-220 K NMR 6,8 hindered
rotation axial rotation K4C60 T lt 250 K 250
K lt T lt 580 K XRD 7,3 bct ordered
anions_at_bco molecular axis or nonparallel
with c merohedral disorder_at_bct stagge
red static distortion static JTE
or dynamic JTE potential field of
molecular JTE counterions dominates dominate
s
D2h D3d/D5d T lt 400 K T gt
400K hindered rotation quasi-isotropic
rotation T lt 350 K T gt 350 K bco bct o
rdered anions molecular axis nonparallel
with c staggered static
distortion static JTE or dynamic
JTE potential field of molecular
JTE counterions dominates dominates