Charge donation by calcium into the t[sub 1g] band of C[sub 60]

Journal Article · Fri Dec 04 00:00:00 EST 1992 · Science (Washington, D.C.); (United States)

DOI:https://doi.org/10.1126/science.258.5088.1638· OSTI ID:7123056

Wertheim, G K; Buchanan, D N.E.; Rowe, J E ^[1]

---

1. AT T Bell Labs., Murray Hill, NJ (United States)

Photoemission spectra of compounds prepared by the reaction of C[sub 60] films with calcium show two distinct metallic phases, whereas alkali-doped C[sub 60] films have only one. In the first phase the bulk t[sub 1u] band, derived from the lowest unoccupied molecular orbital of C[sub 60], is partially occupied. This is followed by an insulating phase that has the composition Ca[sub 3]C[sub 60] in which the t[sub 1u] band is filled and has properties analogous to those of K[sub 6]C[sub 60]. Continued exposure to calcium produces a second metallic phase in which electrons are donated into the t[sub 1g] band. The superconductivity of Ca[sub 5]C[sub 60] is associated with the t[sub 1g] band. 6 refs., 3 figs.

• OSTI ID: 7123056
• Journal Information: Science (Washington, D.C.); (United States), Vol. 258:5088; ISSN 0036-8075
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CALCIUM CARBIDES
SUPERCONDUCTIVITY
FULLERENES
POTASSIUM CARBIDES
SUPERCONDUCTING FILMS
EMISSION SPECTRA
ANNEALING
CHEMICAL REACTIONS
CRYSTAL DOPING
DOPED MATERIALS
PHASE STUDIES
PHOTOEMISSION
TEMPERATURE DEPENDENCE
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
CARBIDES
CARBON
CARBON COMPOUNDS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
EMISSION
FILMS
HEAT TREATMENTS
MATERIALS
NONMETALS
PHYSICAL PROPERTIES
POTASSIUM COMPOUNDS
SECONDARY EMISSION
SPECTRA
360602* - Other Materials- Structure & Phase Studies