Geometric structures and stabilities of CuSin clusters (n=8, 10, 12)

The geometric structures and stabilities of CuSin (n = 8, 10, 12) clusters were studied using a hybrid density functional method (B3LYP). Eight isomers were found for CuSi8, 21 isomers for CuSi10 and five isomers for CuSi12. The stabilities of CuSin can be well related to the stabilities of Sin. The Si frameworks are kept nearly unchanged and Cu is located at a substitutional site in many isomers of CuSin, especially for CuSi10. The obtained results can be used to understand well the observations in mass spectrometric experiments. The high abundance of CuSi10 in the experimental mass spectrum is attributed to the enhanced stability of CuSi10 over neighboring clusters and the existence of a large number of low-lying isomers. (C) 2001 Elsevier Science BN. All rights reserved.