Aurophilic attraction

Hayashi, A., Olmstead, M.M., Attar, S. and Balch, A.L. (2002) Crystal chemistry of the Gold (I) trimer, Au3(NC5H4)3 formation of hourglass figures and self-assodation through aurophilic attraction. Journal of the American Chemical Society, 124, 5791-5795. 

Pyykkd, P. and Zhao, Y.-F. (1991) Ab initio calculations on the (ClAuPH )2 dimer with relativistic pseudopotential Is the aurophilic attraction a correlation effect Angewandte Chemie International Edition, 30, 604—605. 

Runeberg, N., Schiitz, M. and Werner, H.-J. (1999) The aurophilic attraction as interpreted by local correlation methods. Journal of Chemical Physics, 110, 7210-7215. 

Zhang, H.-X. and Che, C.-M. (2001) Aurophilic Attraction and Luminescence of Binuclear Gold(I) Complexes with Bridging Phosphine Ligands ah initio Study. Chemistry - A European Journal, 7, 4887-4893. 

Pan, Q.-J. and Zhang, H.-X. (2003) Aurophilic attraction and excited-state properties of binuclear Au(I) complexes with bridging phosphine and/or thiolate ligands An ah initio study. Journal of Chemical Physics, 119, 4346-4352. 

Pyykkd, P. and Runeberg, N. (2002) Icosahedral WAU]2 A Predicted Closed-Shell Species, Stabilized by Aurophilic Attraction and Relativity and in Accord with the 18-Electron Rule. Angewandte... 

Treatment of 77 with one equivalent of [AuCl(tht)] (tht = tetrahydrothiophene) leads to the type III AuCl bridged pincer complex 79 in high yield (counterion is Cl ) [149]. The unique complex 79 is the only heterodimetallic compound with two metal atoms attached at a carbodiphosphorane carbon(O) atom. The environment at the central carbon atom is planar in 77 and pyramidal in 78 and 79. P-C bond lengths and P-C-P angles in the dication 78 are closely related to those in the neutral Pt complex 36 (Fig. 25). The two metals of 79 attached to the carbon atom are coimected via a very short d -d ° pseudo closed shell interaction with a Pd-Au bond length of 2.8900(3) A a similar bonding situation (aurophilic attraction) is found in the gold complex 29 shown in Fig. 23. 

Complexes with phosphorus or arsenic as the central atom have been synthesized from silylpricogenides and [Au3(p,-0)(PR3)3]+ or [Au(PR3)]BF4 [95, 105-108]. As commented above, the structure of [Au4( j,-As)(PPh3)4]+ does not display the classical tetrahedral geometry towards the As center [95]. The arsenic atom is situated in the apex of a square pyramid, with the lone electron pair allocated to the As apex. This fact would be in agreement with other situations in which the final geometry of the molecules is influenced by the aurophilic attraction, and supports the idea that the stabilization of the final compound is based on the presence of aurophilic interactions which probably are less favorable in a tetrahedral geometry for arsenic, in comparison with nitrogen, due to the different size of these atoms. 

Aurophilic attraction has been almost synonymous with Au(I)-Au(I) attraction. However some complexes which contain short d10-d8 Au(I)-Au(III) and d8-d8 Au... 

In the dinuclear complex [l,3-C6H4(OPPh2AuCl)2] [16] the molecules also form loosely associated dimers due to the presence of weak Au- -Cl contacts of3.407(2) and 3.616(2) A, which are also reported to be aided by aurophilic attractions, as indicated in Figure 5.4, although the shortest gold-gold contact between... 

As described above, among the several closed-shell metal ions that form luminescent supramolecular entities with gold, thallium(I) forms the most numerous examples. While aurophilic attractions can be considered the upper extreme of the metallophilic interactions (with values up to 46 kJ mol-1), intermetallic contacts involving T1(I) centers appear as the weakest ones (even <20 kJ mol-1),46 which is explained by the enhancement of the Au---Au interactions and the weakening of the Van der Waals attractions between the s2 metal atoms produced by the relativistic effects.47 Nevertheless, the complexes in which this interaction appears are surprisingly stable, with additional electrostatic, packing forces, or the ligand architecture, responsible for this fact. 

A fine example of the aurophilic attraction acting against steric forces is the adduct [(AuL)5(/i5-N)] + 2[AuCl(PMe3)] (43, Scheme 16) in which each [AuCfPMei)] molecule interacts with two of the equatorial gold atoms of the cationd ... 

A particular case is that of d -d secondary interactions, first identified in gold compounds and described as aurophilic attraction [78-80], later generalized as metallophilic attraction [81]. This leads to supramolecular self-assembly in many gold compounds, especially when associated with three-center Au- -C Au bonds, and can be also found in other d metal compounds, such as silver, gold, and thallium complexes. Such supermolecules are illustrated by the quasi-cyclic pen-tamers Au5(Mes)5 and Cus(Mes)5, 33, and the tetramer Ag4(Mes)4, 34 [82]. 

Runebeig N, Schutz M, Wemer HJ (1999) The aurophilic attraction as intoineted by local conelation methods. J Chem Phys 110(15) 7210-7215. doi 10.1063/1.478665... 

Aurophilic attractions are also involved in the remarkable behavior of the trinuclear complex, Au3(MeN=COMe)3. The colorless cyclic complex, whose structure is shown in Figure 3.9, crystallizes in three polymorphic forms, one of which contains prismatic stacks of the gold trimers [35]. When irradiated with UV light these crystals prodnce a long-lived yellow anission. If solvent is dropped on these photoexcited crystals, bright bnrsts of light are anitted [36,37]. This process... 

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