Trends in the structure and bonding of noble metal clusters -: art. no. 165403

被引:518
作者
Fernández, EM
Soler, JM
Garzón, IL
Balbás, LC
机构
[1] Univ Valladolid, Dept Fis Teor, E-47011 Valladolid, Spain
[2] Univ Autonoma Madrid, Dept Fis Mat Condensada, E-28049 Madrid, Spain
[3] Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 01000, DF, Mexico
[4] Univ Valladolid, Dept Fis Teor, E-47011 Valladolid, Spain
关键词
D O I
10.1103/PhysRevB.70.165403
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We present a systematic study of the electronic properties and the geometric structure of noble metal clusters X-n(nu) (X=Cu, Ag, Au; nu=-1,0,+1; nless than or equal to13 and n=20), obtained from first-principles generalized gradient approximation density functional calculations based on norm-conserving pseudopotentials and numerical atomic basis sets. We obtain planar structures for the ground state of anionic (nu=-1), neutral (nu=0), and cationic (nu=1) species of gold clusters with up to 12, 11, and 7 atoms, respectively. In contrast, the maximum size of planar clusters with nu=-1,0,+1 are n=(5,6,5) for silver and (5,6,4) for copper. For X-20 we find a T-d symmetry for gold and a compact C-s structure for silver and copper. Our results for the cluster geometries agree partially with previous first-principles calculations, and they are in good agreement with recent experimental results for anionic and cationic gold clusters. The tendency to planarity of gold clusters, which is much larger than in copper and silver, is strongly favored by relativistic effects, which decrease the s-d promotion energy and lead to hybridization of the half-filled 6s orbital with the fully occupied 5d(z)(2) orbital. That picture is substantiated by analyzing our calculated density matrix for planar and three-dimensional clusters of gold and copper. The trends for the cohesive energy, ionization potentials, electron affinities, and highest accupied and lowest unoccupied molecular orbital gap, as the cluster size increases, are studied in detail for each noble metal and rationalized in terms of two- and three-dimensional electronic shell models. The most probable fragmentation channels for X-n(nu) clusters are in very good agreement with available experiments.
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页码:1 / 14
页数:14
相关论文
共 88 条
[31]   On the electronic and atomic structures of small AuN- (N=4-14) clusters:: A photoelectron spectroscopy and density-functional study [J].
Häkkinen, H ;
Yoon, B ;
Landman, U ;
Li, X ;
Zhai, HJ ;
Wang, LS .
JOURNAL OF PHYSICAL CHEMISTRY A, 2003, 107 (32) :6168-6175
[32]   Bonding in Cu, Ag, and Au clusters:: Relativistic effects, trends, and surprises -: art. no. 033401 [J].
Häkkinen, H ;
Moseler, M ;
Landman, U .
PHYSICAL REVIEW LETTERS, 2002, 89 (03) :334011-334014
[33]   DELOCALIZED ELECTRONIC STATES IN SMALL CLUSTERS - COMPARISON OF NAN, CUN, AGN, AND AUN CLUSTERS [J].
HANDSCHUH, H ;
CHA, CY ;
MOLLER, H ;
BECHTHOLD, PS ;
GANTEFOR, G ;
EBERHARDT, W .
CHEMICAL PHYSICS LETTERS, 1994, 227 (4-5) :496-502
[34]   Formation and fragmentation of negative metal clusters [J].
Institute of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark ;
不详 .
Physical Review A - Atomic, Molecular, and Optical Physics, 2001, 63 (02) :023201-023201
[35]   Time-resolved photofragmentation of stored silver clusters Agn+ (n=8-21) [J].
Hild, U ;
Dietrich, G ;
Kruckeberg, S ;
Lindinger, M ;
Lutzenkirchen, K ;
Schweikhard, L ;
Walther, C ;
Ziegler, J .
PHYSICAL REVIEW A, 1998, 57 (04) :2786-2793
[36]   PHOTOELECTRON-SPECTROSCOPY OF METAL CLUSTER ANIONS - CUN-, AGN-, AND AUN- [J].
HO, J ;
ERVIN, KM ;
LINEBERGER, WC .
JOURNAL OF CHEMICAL PHYSICS, 1990, 93 (10) :6987-7002
[37]   Two-dimensional magic numbers in mass abundances of photofragmented bimetallic clusters [J].
Janssens, E ;
Tanaka, H ;
Neukermans, S ;
Silverans, RE ;
Lievens, P .
NEW JOURNAL OF PHYSICS, 2003, 5 :46.1-46.10
[38]   Characterization of copper clusters through the use of density functional theory reactivity descriptors [J].
Jaque, P ;
Toro-Labbé, A .
JOURNAL OF CHEMICAL PHYSICS, 2002, 117 (07) :3208-3218
[39]   Structure and stability of small copper clusters [J].
Jug, K ;
Zimmermann, B ;
Calaminici, P ;
Köster, AM .
JOURNAL OF CHEMICAL PHYSICS, 2002, 116 (11) :4497-4507
[40]   Au20:: A tetrahedral cluster [J].
Li, J ;
Li, X ;
Zhai, HJ ;
Wang, LS .
SCIENCE, 2003, 299 (5608) :864-867