Structural differences in two polymorphs of tetra-kis-(dimethylamino)-ethylene-C{sub 60}: An x-ray diffraction study
Journal Article
·
· Physical Review. B, Condensed Matter and Materials Physics
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Okayama 700-8530 (Japan)
A type of low-temperature structure for ferromagnetic {alpha}-tetra-kis (dimethylamino)-ethylene (TDAE)-C{sub 60} is proposed on the basis of low-temperature x-ray analysis. We observed that intense superlattice reflections with odd indices successively appeared below T{sub s}=170 K. The space group symmetry of the low-temperature phase is determined to be P2{sub 1}/n. Two inequivalent C{sub 60} sites exist in the low-temperature phase, which are indispensable to the orbital ordering model of C{sub 60}. The contact configuration for the neighboring C{sub 60}s along the stacking c direction is uniquely determined. The double bond between the hexagons faces the neighboring pentagon. We found that the surrounding TDAE molecules shift along the c axis ({approx}0.07 A) and that these shifts correlate perfectly to the alignment of C{sub 60}. This result indicates that the steric effect between C{sub 60} and TDAE molecules plays an important role in the orientational ordering of C{sub 60}. On the other hand, in the {alpha}{sup '} phase, no structural phase transition was observed below 30 K. This indicates that all the C{sub 60}s are crystallographically equivalent. Structural differences separate the magnetic peculiarities of the two polymorphs in TDAE-C{sub 60}.
- OSTI ID:
- 20718997
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 17 Vol. 71; ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
Similar Records
Electronic and vibrational structures of countercation of tetrakis(dimethylamino)ethylene (TDAE)-C{sub 60}. Neutral and cationic states of TDAE
Magnetic properties of organic ferromagnetic TDAE-C{sub 60} single crystals and thin films[Tetrakis(dimethylamino)ethylene]
Electronic states and electrical conductivity of the Si(111) native oxide surface adsorbed with electron donor tetrakis(dimethylamino)ethylene
Journal Article
·
Wed Mar 06 23:00:00 EST 1996
· Journal of Physical Chemistry
·
OSTI ID:226757
Magnetic properties of organic ferromagnetic TDAE-C{sub 60} single crystals and thin films[Tetrakis(dimethylamino)ethylene]
Conference
·
Wed Jul 01 00:00:00 EDT 1998
·
OSTI ID:20034117
Electronic states and electrical conductivity of the Si(111) native oxide surface adsorbed with electron donor tetrakis(dimethylamino)ethylene
Journal Article
·
Sun Aug 28 00:00:00 EDT 2016
· Journal of Applied Physics
·
OSTI ID:22598844