Cluster Calculation of B and Al Impurities in Amorphous Silicon


We report our results of molecular structure calculations for B and Al impurities. From our unoptimized ab initio calculations, we found the molecular electronic wave function to be unstable for both impurities. This instability was removed through a geometry optimization process. Local densities of states (LDOS) were computed for the optimized geometries. They show a rise of a peak at the tail of the valence LDOS; this feature is due to p orbitals of B and Al. The contribution is slightly higher for B than for Al impurities. Charge contour plots are presented.

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JAC acknowledges the generous allocation of CPU time on the Cray YMP 4/432 at DGSCA-UNAM. JAC wants to thank Mrs. Sara Jiménez for the excelent library service she provides at the IIM-UNAM.

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Correspondence to J. A. Cogordan.

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Cogordan, J.A., Sansores, L.E. & Valladares, A.A. Cluster Calculation of B and Al Impurities in Amorphous Silicon. MRS Online Proceedings Library 291, 355–360 (1992).

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