First principles calculations on Na and K-adsorbed diamond(100) surface

Journal Article · Tue Aug 01 04:00:00 EDT 2006 · Chemical Physics, 326(2-3):308-314

DOI:https://doi.org/10.1016/j.chemphys.2006.02.005· OSTI ID:890106

Nie, JL; Xiao, H Y; Zu, Xiaotao; Gao, Fei

Self-consistent, periodic, density functional theory calculations, using PW91 functional, have been performed to investigate Na and K adsorption on the C(100)(2?1) surface. Our calculations showed that Na and K adatoms preferred to occupy valley-bridge sites at the coverage (?) of 0.5ML. For the coverage of 1ML, the combination of pedestal site and valley-bridge site turned out to be energetically favored. These findings are found to be consistent with those obtained for alkali-metal adsorption on silicon and germanium surfaces. Two desorption peaks named ? and ? for K adsorption have been observed and assigned to pedestal or bridge site and valley-bridge sites experimentally, while our results showed that the ? and ? states should be ascribed to pedestal site and valley-bridge sites and the combination of bridge and valley-bridge site is not the local minima. Work function analysis showed that when Na and K are adsorbed on diamond surface, the work function will decrease linearly with increasing coverage, up to a minimum, and finally increase again because of the depolarization of the adsorbate, agreeing well with experiments.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 890106
• Report Number(s): PNNL-SA-48519
• Journal Information: Chemical Physics, 326(2-3):308-314, Journal Name: Chemical Physics, 326(2-3):308-314
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ADSORPTION
DENSITY FUNCTIONAL METHOD
DIAMONDS
Density functional theory calculations
Diamond
POTASSIUM
Potassium
SODIUM
SORPTIVE PROPERTIES
Sodium
WORK FUNCTIONS
Work function