tailieunhanh - Neutral and cationic titanium doped silicon clusters: Growth mechanism and stability

We report ab-initio study on neutral and cationic titanium-doped silicon clusters TiSin 0/+ (n = 1-10). The growth patterns for both neutral and charged clusters are revealed. The neutral TiSin clusters follow a consistent rule of addition: the larger TiSin cluster is built up by adding a Si atom on the smaller TiSin-1 cluster. | Vietnam Journal of Science and Technology 55 (6A) (2017) 83-94 NEUTRAL AND CATIONIC TITANIUM-DOPED SILICON CLUSTERS: GROWTH MECHANISM AND STABILITY Nguyen Thi Ngoc Tuyet1, Tran Ha Giang1, Phan Thi Thu Thuy1, Pham Ngoc Thach2, Vu Thi Ngan2, * 1 Institute for Computational Science and Technology (ICST), SBI building, Quang Trung Software City, , Ho Chi Minh City, Viet Nam 2 Department of Chemistry, Laboratory for Computational Chemistry and Modelling, Quy Nhon University, 170 An Duong Vuong street, Quy Nhon city, Binh Dinh province, Viet Nam * Email: vuthingan@ Received: 15 June 2017; Accepted for publication: 2 December 2017 ABSTRACT We report ab-initio study on neutral and cationic titanium-doped silicon clusters TiSin0/+ (n = 1-10). The growth patterns for both neutral and charged clusters are revealed. The neutral TiSin clusters follow a consistent rule of addition: the larger TiSin cluster is built up by adding a Si atom on the smaller TiSin-1 cluster. However, the Ti atom prefers to substitute at a highcoordination position to form the cationic clusters. The neutral TiSin clusters is more stable than the pure Sin+1 clusters while the cationic TiSin+ is less stable than the pure ones. Both neutral and cationic clusters tend to loss Si atom rather than Ti atoms. Keywords: doped-silicon clusters; growth mechanism; stability; density functional theory; cationic cluster. 1. INTRODUCTION The importance of silicon in many technological applications together with the explosion of cluster science leads to an expansion of studies on silicon clusters in recent years [1 - 4]. There is currently a strong interest in the prospect of producing novel materials consisting of small atomic clusters, and in particular silicon clusters [5 - 7]. Many studies have been published on geometrical structures and spectroscopic properties of the pure silicon clusters. For instant, the most recent studies on pure silicon clusters done on ionization energy measurement .