- Collection:
- Atlanta University and Clark Atlanta University Theses and Dissertations
- Title:
- Structural and electronic properties of boron nano structures: A dispersion-corrected density functional study, 2012
- Creator:
- Gunasinghe, Rosi Najeela
- Date of Original:
- 2010/2019
- Subject:
- Degrees, Academic
Dissertations, Academic - Location:
- United States, Georgia, Fulton County, Atlanta, 33.749, -84.38798
- Medium:
- theses
dissertations - Type:
- Text
- Format:
- application/pdf
- Description:
- We have revisited the general constructing schemes for a large family of stable hollowboron fullerenes with 80 + 8n (n = 0,2,3,...) atoms. In contrast to the hollow pentagon boron fullerenes with 12 hollow pentagons, the stable boron fullerenes constitute 12 filled pentagons and 12 additional hollow hexagons, which are more stable than the empty pentagon boron fullerenes including the magic B80 buckyball. Based on results from first-principles density-functional calculations, an empirical rule for filled pentagons is proposed along with a revised electron counting scheme to account for the improved stability and the associated electronic bonding feature. We have also studied the relative stability of various boron fullerene structures and structural and electronic properties of B80 bucky ball and boron nanotubes via dispersion-corrected density-functional calculations. Our results reveal that the energy order of fullerenes strongly depends on the exchange-correlation functional employed in the calculation and the vibrational stability for the icosahedral B80 with the inclusion of dispersion corrections, in contrast to the instability to a tetrahedral B80 with puckered capping atoms from preceding density functional theory calculations. Similarly, the dispersion-corrected density-functional calculations yield non-puckered boron nanotube conformations and an associated metallic state for zigzag tubes. A systematic study elucidates the importance of incorporating dispersion forces to account for the intricate interplay of two and three centered bonding in boron nanostructures.
Date of award: 5/1/2012
Degree type: thesis
Degree name: Master of Science (MS)
Granting institution: Clark Atlanta University
Department: School of Arts and Sciences, Physics
Advisor: Wang, Xiao-Qian
Advisor: Williams, Michael D.
Advisor: Msezane, Alfred - Metadata URL:
- http://hdl.handle.net/20.500.12322/cau.td:2012_gunasinghe_rosi_n
- Holding Institution:
- Atlanta University Center Robert W. Woodruff Library
- Rights:
-
