Structure and phase transition of the 6,5-annulene isomer of C[sub 61]H[sub 2]

Journal Article · Sun May 01 04:00:00 EDT 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.49.12572· OSTI ID:5113008

Lommen, A N; Heiney, P A; Vaughan, G B.M. ^[1]; Stephens, P W ^[2]; Liu, D ^[3]; Li, D; Smith, A L ^[4]; McGhie, A R ^[5]; Strongin, R M; Brard, L; Smith, III, A B ^[6]

---

1. Department of Physics and Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)
2. Department of Physics, State University of New York at Stony Brook, Stony Brook, New York 11794 (United States)
3. SUNY X3 Beamline at the National Synchrotron Light Source, Upton, New York 11973 (United States)
4. Chemistry Department, Drexel University, Philadelphia, Pennsylvania 19104 (United States)
5. Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)
6. Department of Chemistry and Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

We have used differential scanning calorimetry and x-ray diffraction to study the crystalline phases of the 6,5-annulene isomer of C[sub 61]H[sub 2]. At 308 K the methylenated fullerenes are orientationally disordered in a face-centered cubic lattice with lattice parameter 14.19[plus minus]0.02 A. Below [ital T][sub [ital c]]=290 K the symmetry is lowered to [ital Pa][bar 3], a simple-cubic structure. At 20 K the lattice parameter is 14.06[plus minus]0.02 A, with substantial statistical disorder remaining. The transition temperature in C[sub 61]H[sub 2] is slightly higher than in C[sub 60]O and higher still than in C[sub 60], but the three compounds exhibit orientationally ordering transitions between qualitatively similar phases.

• DOE Contract Number: FG02-86ER45254
• OSTI ID: 5113008
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 49:18; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
CALORIMETRY
CARBON
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CUBIC LATTICES
ELEMENTS
FCC LATTICES
FULLERENES
HYDROGEN ADDITIONS
ISOMERS
LATTICE PARAMETERS
NONMETALS
PHASE TRANSFORMATIONS