Melting Behaviour of Core-Shell Structured Ag--Rh Bimetallic Clusters
PAN Yang, CHENG Dao-Jian, HUANG Shi-Ping, WANG Wen-Chuan
Division of Molecular and Materials Simulation, Key Lab for Nanomaterials (Ministry of Education), Beijing University of Chemical Technology, Beijing 100029
Melting Behaviour of Core-Shell Structured Ag--Rh Bimetallic Clusters
PAN Yang;CHENG Dao-Jian;HUANG Shi-Ping;WANG Wen-Chuan
Division of Molecular and Materials Simulation, Key Lab for Nanomaterials (Ministry of Education), Beijing University of Chemical Technology, Beijing 100029
摘要The melting behaviour of four typical core-shell structured 309-atom Ag--Rh bimetallic clusters, with decahedral and icosahedral geometric configurations, is investigated by using molecular dynamics simulation, based on the Sutton--Chen potential. The initial atomic configurations are obtained from semi-grand canonical ensemble Monte Carlo simulations. It is found that the melting point temperature Tm increases with the mole fraction of Rh in the bimetallic clusters, and Tm of Ag--Rh icosahedral clusters is higher than those of Ag--Rh decahedral clusters with the same Rh mole fraction. It is also found that the Ag atoms lie on the surface of Ag--Rh bimetallic clusters even after melting.
Abstract：The melting behaviour of four typical core-shell structured 309-atom Ag--Rh bimetallic clusters, with decahedral and icosahedral geometric configurations, is investigated by using molecular dynamics simulation, based on the Sutton--Chen potential. The initial atomic configurations are obtained from semi-grand canonical ensemble Monte Carlo simulations. It is found that the melting point temperature Tm increases with the mole fraction of Rh in the bimetallic clusters, and Tm of Ag--Rh icosahedral clusters is higher than those of Ag--Rh decahedral clusters with the same Rh mole fraction. It is also found that the Ag atoms lie on the surface of Ag--Rh bimetallic clusters even after melting.
[1] Zhang X and Chan K Y 2002 J. Mater. Chem. 12 1203 [2] Son S U et al%, Jang Y, Park J, Na H B, Park H M, Yun H J, Lee J and Hyeon T2004 J. Am. Chem. Soc. 126 5026 [3] Sao-Joao S et al%, Giorgio S, Penisson J M, Chapon C, Bourgeois S and Henry C2005 J. Phys. Chem. B 109 342 [4] Baletto F et al %, Mottet C and Ferrando R2003 Phys. Rev. Lett. 90 135504 [5] Chui Y H and Chan K Y 2004 Mol. Simulat. 30 679 [6] Wang G F et al %, Hove M A V, Ross P N and Baskes M I2005 J. Chem. Phys. 122 024706 [7] Marks L D 1984 Philos. Mag. A 49 81 [8] Baletto F et al %, Mottet C, Rapallo A, Rossi G and Ferrando R2004 Surf. Sci. 566--568 192 [9] Harpeness R and Gedanken A 2004 Langmuir 20 3431 [10] Baletto F et al %, Mottet C and Ferrando R2002 Phys. Rev. B 66155420 [11] Marcelo M M et al %, Sergio A D and Ezequiel P M L2005 J.Chem. Phys. 123 184505 [12] Wang G F et al %, Hove M A V, Ross P N and Baskes M I2004 J. Chem.Phys. 121 5410 [13] Wang B L et al %, Chen X S, Chen G B and Wang G H2004 Surf. Rev. Lett. 11 15-20 [14] Hoof T V and Hou M 2005 Phys. Rev. B 72 115434 [15] Angelidis T N and Tzitzios V 2003 Appl. Catal. B:Environ. 41 357 [16] Angelidis T N and Tzitzios V 2003 Ind. Eng. Chem. Res. 42 2996 [17] Kotsifa A et al %, Halkides T I, Konarides D I and Verykios X E2002 Catal. Lett. 79 113 [18] Qiu S T et al %, Luo Y H, Ren Y, Zhao J J and Wang G H2000 Journal of Nanjing University (Natural Science Edition) 36 434 (in Chinese) [19] Mainardi D S and Balbuena P B 2001 Int. J. QuantumChem. 85 580 [20] Foiles S M 1985 Phys. Rev. B 32 7685 [21] Foiles S M, Dowben P A and Miller A 1990 (Boca Raton: CRC) [22] Deng H Q et al %, Hu W Y, Shu X L, Zhao L H and Zhang B W2002 Surf. Sci. 517 177 [23] Deng H Q et al %, Hu W Y, Shu X L and Zhang B W2003 Surf. Sci. 54395 [24] Cheng D J et al %, Huang S P and Wang W C2006 Eur. Phys. J. D 39 41 [25] Cheng D J et al %, Huang S P and Wang W C2006 Phys. Rev. B 74 064117 [26] Cheng D J et al %, Wang W C and Huang S P2006 J. Phys. Chem.B 110 16193 [27] Smith W and Forester T R 1996 DL\_POLY Daresbury Laboratory(Daresbury) [28] Sutton A P and Chen J 1990 Phil. Mag. Lett. 61 139 [29] RafII-Tabar H and Sutton A P 1991 Phil. Mag. Lett. 63 217 [30] Allen M P and Tildesley D J 1986 Computer Simulation ofLiquids (Oxford: Clarendon) [31] Aguado A and L\'opez M J 2005 Phys. Rev. B 71 075415 [32] Chacko S, Kanhere D G and Blundell S A 2005 Phys. Rev.B 71 155407 [33] Sankaranarayanan S K R S, Bhethanabotla V R and Joseph B 2005 Phys. Rev. B 71 195415
2007, Vol. 24 
