A Density Functional Investigation on C(2)Aun(+) (n=1, 3, 5) and C(2)Aun (n=2, 4, 6): from Gold Terminals, Gold Bridges, to Gold Triangles

作者：Li Da Zhi; Li Si Dian^*

来源：Journal of Cluster Science, 2011, 22(3): 331-341.

DOI：10.1007/s10876-011-0383-5

• Dicarbon aurides
• Structures
• DFT
• Gold triangles
• 3c-2e bonds

A systematic density functional theory investigation on C2Au (n) (+) (n = 1,3,5) and C2Au (n) (n = 2,4,6) indicates that gold atoms serve as terminals (-Au) in the chain-like C-s C2Au+ (C=C-Au+) and D-ah C2Au2 (Au-Ca parts per thousand C-Au) and as bridges (-Au-) in the side-on coordinated C-2v C2Au3 (+) ([Au-Ca parts per thousand C-Au]Au+) and C-s C2HAu2 (+)([H-Ca parts per thousand C-Au]Au+). However, when the number of gold atoms reaches four, they form stable gold triangles (-Au-3) in the head-on coordinated C-2v C2Au4 (Au-Ca parts per thousand C-Au-3) and the side-on coordinated C-2v C2Au5 (+) ([Au-Ca parts per thousand C-Au]Au-3 (+)). Similar -Au-3 triangular units exist in the head-on coordinated C-2v C2HAu3 (H-Ca parts per thousand C-Au-3) and D-2d C2Au6 (Au-3-Ca parts per thousand C-Au-3). The existence of stable -Au-3 triangular units in small dicarbon aurides is significant and intriguing. The high stability of Au-3 triangles originates from the fact that an equilateral D-3h Au-3 (+) cation possesses a completely delocalized three-center-two-electron (3c-2e) sigma bond and therefore is sigma-aromatic in nature. The extension from H/Au analogy to H/Au-3 analogy established in this work may have important implications in designing new gold-containing catalysts and nano-materials.

• 出版日期2011-9
• 单位滨州学院; 山西大学; 忻州师范学院