ISSN:
0020-7608
Keywords:
Computational Chemistry and Molecular Modeling
;
Atomic, Molecular and Optical Physics
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The linear combinations of Gaussian-type orbitals-fitting function (LCGTO-FF) technique has been used to calculate the binding energy and electronic band structure of a 3-atom-thick film extracted from bulk LiBeH3 in the cubic perovskite structure. The film is composed of an interior layer of LiH sandwiched between two exterior layers of BeH2, i.e., there are eight atoms per unit cell (1 Li, 2 Be, and 5 H). The calculated cubic lattice parameter for the 3-layer (a = 5.74 au) lies roughly midway between the previously published theoretical lattice parameters for a BeH2 monolayer (5.51 au) and bulk LiBeH3 in the cubic perovskite structure (5.89 au). The 3-layer film is predicted to be a semimetal (i.e., zero-gap semiconductor), unlike both bulk LiBeH3 which is predicted to be a semiconductor, and monolayer BeH2, which is predicted to be a good metal. The metallic nature of the 3-layer is due to a Be surface state that cuts across the other valence bands of the film, in good agreement with an earlier prediction that cubic perovskite LiBeH3 cleaved to expose a BeH2 layer would provide a metallic surface on an insulating substrate. The fact that the density of states goes to zero at the Fermi level is a direct result of the symmetries of the one-electron states.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560400856
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