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The reaction of [AuCl(tht)] (tht = tetrahydrothiophene) with SbMes(n)Ph(3-n) (n = 3 (1), 2 (2), 1 (3)) produces the 1:1 adducts [AuCl(SbMes(n)Ph(3-n))] (n = 3 (4), 2 (5), 1 (6)), with a Sb-Au-Cl environment, regardless of the molar ratio used (1:1 to 1:4). Addition of the same stibines to [Au(tht)(2)]ClO(4) (molar ratio 1:1 to 1:4) results in isolation of the 1:2 adducts [Au(SbMes(n)Ph(3-n))(2)]ClO(4) (n = 3 (7), 2 (10)), containing linear Sb-Au-Sb fragments, or the 1:3 adduct [Au(SbMesPh(2))(3)]ClO(4) (11), with a quasi trigonal planar AuSb(3) core. The same 1:2 cations are produced when [Au(tht)(2)]CF(3)SO(3) is reacted with 1 or following a rearrangement process when 4 is treated with AgSbF(6), that is, [Au(SbMes(3))(2)]X (X = CF(3)SO(3) (8), SbF(6) (9)). The compounds were characterized by spectroscopic methods, and the molecular structures of 2-4, 7, 8.2CDCl(3), 9, and 11 were established by single-crystal X-ray diffraction. Theoretical calculations were carried out on model systems of type ER(3) and [Au(ER(3))(n)](+) (E = P or Sb; R = Ph or Mes; n = 2, 3, or 4) to gain insight into the bonding nature of SbR(3) ligands in homoleptic gold-stibine adducts, in comparison with phosphine-gold(I) compounds. Steric effects govern the coordination of stibines with mesityl substituents. A preference for higher coordination numbers is observed for SbPh(3) when compared with PPh(3) and experimentally observed C-Sb-C and Sb-C structural distortions of stibines upon coordination are reproduced theoretically.

The dinuclear complex [[Tl(eta6-toluene)][Au(C6Cl5)2]] (1) displays very intense blue phosphorescence and a rigidochromic behavior in the solid state. The photophysical measurements in a glassy solution display an oligomerization process via metal-metal interactions. Density functional theory calculations show a distortion of the aurate-thallium T shape in the lowest triplet excited state, leading to a triplet metal-to-metal charge-transfer state.

Dinuclear three-coordinate Au(I) complex [Au2{(Ph2Sb)2O}3](ClO4)2 1 displays an interesting phosphorescent behavior in which a large Stokes' shift is observed. Ab initio calculations show that the main distortion for the first triplet excited state, which is responsible for the luminescence behavior of complex 1, is a Jahn-Teller distortion for only one of the Au(I) centers together with a gold-gold distance shortening. This behavior could be extrapolated to other phosphorescent dinuclear three-coordinate Au(I) complexes.

The polymeric linear chain [AuTl(C6Cl5)2]n reacts with three terpyridine-type ligands substituted with thiophene groups containing N-donor centres in different relative positions (L1, L2 and L3), leading to the Au(I)/Tl(I) complexes [AuTl(C6Cl5)2(L1)]n (1), [{AuTl(C6Cl5)2}2(L2)]n (2) and [AuTl(C6Cl5)2(L3)]n (3). X-Ray diffraction studies reveal that L1 acts as a chelate, while L2 and L3 act as bridging ligands, resulting in different coordination indexes for the thallium(I) centre. These structural differences strongly influence their optical properties, and while compounds 2 and 3 emit near the limit of the visible range, complex 1 emits in the infrared region. DFT calculations have also been carried out in order to determine the origin of the electronic transitions responsible for their optical properties. [ABSTRACT FROM AUTHOR]

The synthesis of gold(III) and gold(I)–gold(III) complexes with phosphide bridges is still a matter that requires solutions for their marked instability, in spite of the affinity of this metal in both oxidation states for phosphorous donor ligands. In the course of our studies, we realized that the presence of perhalophenyl groups of the type pentafluorophenyl or 3,5-dichlorotrifluorophenyl in the complexes gives rise to an increase in their stability that eases their isolation and structural characterization. In this paper, we describe two new fully characterized neutral compounds of this type to extend the knowledge on this family of compounds, [{Au(C6Cl2F3)2}2(µ-PPh2)2] (1) and [{Au(C6Cl2F3)2(µ-PPh2)2Au}2] (2). In this work, we analyze the role of the perhalophenyl groups in the stability of these complexes by using quantum chemical topology methodologies, specifically employing an analysis of the non-covalent interactions (NCIs) in real space and evaluating the electrostatic potential surfaces (ESP). Our findings reveal the existence of appreciable π-stacking interactions among the perhalophenyl and phenyl groups in both compounds, significantly contributing to the stability of the systems. [ABSTRACT FROM AUTHOR]

The reactivity of the heterometallic polynuclear complexes [{Au(R)2}2Cu2(MeCN)2]n (R=C6F5, C6Cl5) with the thioether crowns 1,4,7‐trithiacyclononane (L1, [12]aneS3), 1,4,8,11‐tetrathiacyclododecane (L2, [14]aneS4), 1,4,7,10,13,16,19,22‐octathiacyclotetracosane (L3, [24]aneS8), and the quinoline functionalized pendant arm derivatives of the 12‐membered mixed‐donor macrocycles 1‐aza‐,4,7,10‐trithiacyclododecane ([12]aneNS3) and 1,7‐diaza‐4,10‐dithiacyclododecane ([12]aneN2S2), L4 and L5, respectively, was investigated in THF solution. While with L4 and L5 only ionic compounds of general formulation [Cu(L)][Au(R)2] were isolated and structurally characterized (none of them featuring Au⋅⋅⋅Cu interactions), with L1‐L3, beside similar ionic compounds, some heteronuclear complexes of general formulation [{Au(R)2}{Cu(L)}] and featuring Au⋅⋅⋅Cu interactions were also obtained. All of them display rather unusual non‐classical C−H⋅⋅⋅Au hydrogen interactions. The complexes display in the solid state different optical properties related to their structures, which have been studied experimentally and theoretically via TD‐DFT calculations. In particular, all compounds of the type [{Au(R)2}{Cu(L)}] featuring Au⋅⋅⋅Cu metallophilic interactions display luminescence in the solid state both at room temperature (RT) and at 77 K. On the contrary, ionic compounds of general formulation [Cu(L)][Au(R)2], except [Cu(L4)][Au(C6F5)2], are not luminescent. [ABSTRACT FROM AUTHOR]

The reaction among [Au2Ag2(C6F5)4(OEt2)2]n, PbCl2 and terpyridine leads to the polymeric complex [{Au(C6F5)2}2{Pb(terpy)}]n (1). Its crystal structure reveals potential voids close to the lead centres large enough to hold different molecules. The availability of these free sites allows complex 1 to act as a VOC sensor. Thus, when 1 is exposed to different solvent vapours such as acetonitrile, toluene or THF, variations in its solid appearance and its photophysical properties are observed as a consequence of the formation of the new polymorphs [{Au(C6F5)2}2{Pb(terpy)(CH3CN)2}]n (2), [{Au(C6F5)2}2{Pb(terpy)}]n·Tol (3) and [{Au(C6F5)2}2{Pb(terpy)(THF)}]n·THF (4). Each polymorph displays a different emission energy depending on its structure and the presence of metallophilic interactions. In addition, the reversible solvent molecule exchange allows the tuning of the luminescence emissions in the greenish yellow–red range. DFT and TD-DFT calculations were performed to explain the origin of the luminescence of all these complexes. [ABSTRACT FROM AUTHOR]

Au⋅⋅⋅H−X (X=N or C) hydrogen bonding is gaining increasing interest, both in the study of its intrinsic nature and in their operability in different fields. While the role of these interactions has been studied in the stabilization of gold(I) complexes, their role during the minimum free energy reaction pathway of a given catalytic process remains unexplored. We report herein that complex [Au(C≡CPh)(pip)] (pip=piperidine) catalyses the A3‐coupling reaction for the synthesis of propargylamines, thanks to the ability of Au(I) to promote weak hydrogen bonding interactions with the reactants along the free energy profile. Density Functional Theory (DFT) calculations show that these Au⋅⋅⋅H−X interactions play a directing role in the catalysed A3‐coupling. Topological non‐covalent interactions (NCI), interaction region indicator (IRI) and quantum theory of atoms in molecules (QTAIM) analysis in real space of the electron density provide a description of these interactions accurately. [ABSTRACT FROM AUTHOR]

Aggregating gold(I) complexes in solution through short aurophilic contacts promotes new photoluminescent deactivation pathways (aggregation-induced emission, AIE). The time dependence of spontaneous AIE is seldom studied. We examine the behavior of complex [Au(N9-hypoxanthinate)(PTA)] (1) in an aqueous solution with the aid of variable-temperature NMR, time-resolved UV–Vis and photoluminescence spectroscopy, and PGSE NMR. The studies suggest that partial ligand scrambling in favor of the ionic [Au(PTA)2][Au(N9-hypoxanthinate)2] pair followed by anion oligomerization takes place. The results are rationalized with the aid of computational calculations at the TD-DFT level of theory and IRI analysis of the electron density. [ABSTRACT FROM AUTHOR]

MoS2 nanoflowers (NFs) obtained through a hydrothermal approach were used as the substrate for the deposition of tiny spherical bimetallic AuAg or monometallic Au nanoparticles (NPs), leading to novel photothermal-assisted catalysts with different hybrid nanostructures and showing improved catalytic performance under NIR laser irradiation. The catalytic reduction of pollutant 4-nitrophenol (4-NF) to the valuable product 4-aminophenol (4-AF) was evaluated. The hydrothermal synthesis of MoS2 NFs provides a material with a broad absorption in the Vis-NIR region of the electromagnetic spectrum. The in situ grafting of alloyed AuAg and Au NPs of very small size (2.0–2.5 nm) was possible through the decomposition of organometallic complexes [Au2Ag2(C6F5)4(OEt2)2]n and [Au(C6F5)(tht)] (tht = tetrahydrothiophene) using triisopropilsilane as reducing agent, leading to nanohybrids 1–4. The new nanohybrid materials display photothermal properties arising from NIR light absorption of the MoS2 NFs component. The AuAg-MoS2 nanohybrid 2 showed excellent photothermal-assisted catalytic activity for the reduction of 4-NF, which is better than that of the monometallic Au-MoS2 nanohybrid 4. The obtained nanohybrids were characterised by transmission electron microscopy (TEM), High Angle Annular Dark Field—Scanning Transmission Electron Microscopy—Energy Dispersive X-ray Spectroscopy (HAADF-STEM-EDS), X-ray photoelectron spectroscopy and UV-Vis-NIR spectroscopy. [ABSTRACT FROM AUTHOR]

The existence of aurophilic gold(III)⋯gold(III) interactions has for a long time been neglected due to structural arguments and comparison with the aurophilicity of gold(I) compounds. We show with calculations at the CCSD(T) level of theory that the [AuIII(CH3)3(NH3)]2 dimer has a metallophilic dispersion interaction between the gold(III) atoms of 10.5 kJ mol−1. The aurophilic interaction is illustrated by topological QTAIM calculations and IRI analysis. [ABSTRACT FROM AUTHOR]

In this paper, we describe a series of diphenylphosphane and diphenylphosphanide gold(III) and gold(III)/gold(I) complexes containing 3,5-C6Cl2F3 as aryl ligands at gold that have been synthesized due to the arylating and oxidant properties of the new polymeric thallium(III) complex [TlCl(3,5-C6Cl2F3)2]n (1). Its reaction with [Au(3,5-C6Cl2F3)(tht)] (tht = tetrahydrothiophene) produces the gold(III) complex [Au(3,5-C6Cl2F3)3(tht)] (2), which allows the synthesis of the diphenylohosphane derivative [Au(3,5-C6Cl2F3)3(PPh2H)] (3). Its treatment with acetylacetonate gold(I) derivatives leads to two novel AuIII/AuI phosphanido-bridged complexes, [PPN][Au(3,5-C6Cl2F3)3(µ-PPh2)AuCl] (4) and [PPN][{(3,5-C6Cl2F3)3Au(µ-PPh2)}2Au] (5). All these complexes have been characterized, and the crystal structures of 1, 2, 4 and 5 have been established by single crystal X-ray diffraction methods, showing a novel polymeric arrangement in 1. [ABSTRACT FROM AUTHOR]

The reaction of the polymeric heterometallic compound [{Au(C6Cl5)2}Ag]n with the macrocyclic ligands 1‐aza‐4,7,10‐trithiacyclododecane (L1), 1,7‐diaza‐4,11‐dithiacyclododecane (L2), 1‐aza‐4,10‐dithia‐7‐oxacyclododecane (L3) in tetrahydrofuran (THF) and 1 : 1 reaction molar ratio affords the new Au(I)/Ag(I) complexes [{Au(C6Cl5)2}{Ag(L1)}] (1), [{Au(C6Cl5)2}{Ag(L2)}] (2), [{Au(C6Cl5)2}{Ag(L3)}] (3) and [{Au(C6Cl5)2}{Ag(L3)}]2 (4) that have been structurally characterized. Despite 1–3 show the same nature of binuclear complexes, only 3 changes its luminescence properties upon grinding as a consequence of partial amorphization. [ABSTRACT FROM AUTHOR]

The assembly of two different building blocks, [{Au(C6F5)2}{PbCl(terpy)}] (terpy=2,2′:6′:2′′‐terpyridine) and [{Au(C6F5)2}2{Pb(terpy)}]n, acting as terminal or central pieces, respectively, gives rise to a decanuclear complex built via metallophilic and π‐stacking interactions in which the number of AuI⋅⋅⋅AuI and AuI⋅⋅⋅PbII contacts is finely controlled. [ABSTRACT FROM AUTHOR]

Abstract: The crystal structure of the polymeric complex [Au5Ag2Tl3(C6F5)10(L1)2]n (L1=1‐aza‐4,10‐dithia‐7‐oxacyclododecane) displays heterotrimetallic Ag⋅⋅⋅Au⋅⋅⋅Tl moieties and is held by unsupported metallophilic interactions. This complex emits at 500 nm in the solid state. Ab initio calculations show that the large thermodynamic stability that helps the formation of this heterotrimetallic system arises from the combination of dispersive forces and a very large dipole moment in the supramolecular arrangement. [ABSTRACT FROM AUTHOR]

The reactivity of benzimidazol-2-ylidenes with respect to gold nanoparticles (AuNPs) has been investigated using a combined experimental and computational approach. First, the grafting of benzimidazol-2-ylidenes bearing benzyl groups on the nitrogen atoms is described, and comparisons are made with structurally similar N-heterocyclic carbenes (NHCs) bearing other N-groups. Similar reactivity was observed for all NHCs, with 1) the erosion of the AuNPs under the effect of the NHC and 2) the formation of bis(NHC) gold complexes. DFT calculations were performed to investigate the modes of grafting of such ligands, to determine adsorption energies, and to rationalize the spectroscopic data. Two types of computational models were developed to describe the grafting onto large or small AuNPs, with either periodic or cluster-type DFT calculations. Calculations of NMR parameters were performed on some of these models, and discussed in light of the experimental data. [ABSTRACT FROM AUTHOR]

The tetrahedral AuI complexes [Au(GeCl3)L3] (L=PMe3 ( 1), PMe2Ph ( 2), PMePh2 ( 3), PPh3 ( 4)) were synthesized by in situ treatment of the [Au(GeCl3)(tht)] complex with three equivalents of the corresponding tertiary phosphine. The crystal structures of complexes 1 and 3 have been determined through X-ray diffraction studies and show [GeCl3]− fragments bonded to the corresponding [Au(PR3)3]+ units through covalent bonds, leading to a tetrahedral coordination environment for gold. Complexes 3 and 4 show dual phosphorescence in the solid state at 77 K and, in the case of complex 4, an interesting room-temperature mechanochromism effect is observed. Correlated MP2, SCS-MP2, SCS-CC2, and ONIOM MP2/UFF calculations suggest the existence of two largely distorted and thermally connected triplet excited states (T1 and T2) for a model system of complex 4. The AuP3+ moiety can be distorted in two different planes leading to the two triplet excited states T1 and T2, leaving the GeCl3− unit almost unaltered. The emissions of these phosphorescent AuIGeII complexes is mainly ascribed to a metal (gold)-centered (3MC) transition with some contribution from the [GeCl3]− fragments. [ABSTRACT FROM AUTHOR]

Two organometallic complexes, named [Hg(2-C6H4PPh2)2] (1) and [{Au(C6F5)}2{Hg(2-C6H4PPh2)2}] (2) have been studied as quenchers of the fluorescence of naphthalene. Positive deviations were observed in the Stern-Volmer (S-V) plots for both quenchers. The analyses of the data reveal the existence of transient components in the dynamic quenching. The diffusion coefficients of these complexes have been obtained by two different methods, through the Stokes-Einstein equation, and from ¹H PGSE NMR experiments. With these values, and taking into account the experimental KT constants, the radii of the transient quenching spheres were obtained, which show unusually large values. [ABSTRACT FROM AUTHOR]

Ag-Au core-shell nanoprisms were obtained through the deposition of Au atoms over hexadecylamine-stabilized Ag nanoparticles through the mild decomposition of an organometallic AuI precursor. The effects of the amount of precursor [Au(C6F5)(tht)] (tht = tetrahydrothiophene) added and the reaction time on the size, shape, and composition of the core-shell Ag-Au nanostructures obtained have been studied by TEM, high-angle annular dark field/scanning transmission electron microscopy (HAADF-STEM), EDS, UV/Vis, and 19F NMR spectroscopic analysis. The anisotropic growth of the prismatic metallic shell and its composition has been controlled through the addition of different amounts of AuI precursor, thus leading to a delicate tuning of the plasmonic properties of these nanostructures. [ABSTRACT FROM AUTHOR]

Tetrahedral Au¹ complexes [L3Au(SnCl3)l (L = PMe3 (1), PMe2Ph (2), PMePh2 (3), and PPh3 (4)) were prepared by treatment of the [(tht)Au(SnCl3)l (tht = tetrahydrothiophene) complex with three equivalents of the corresponding tertiary phosphine. The crystal structures of complexes 1-4 have been determined through X-ray diffraction studies showing, in all cases, [SnCl3]-fragments covalently bonded to the corresponding [Au(PR3)3]+ units, which leads to a tetrahedral coordination environment for gold. Complexes 3 and 4 show phosphorescence in the solid state at room temperature and 77 K that is largely redshifted relative to the free [Au(PR3)3]+ and [SnCl3]- counterparts. Correlated MP2, SCS-MP2, and ONIOM MP2/UFF calculations suggest a largely distorted lower triplet excited state (T,) for each model system. The AuP3+ moiety is distorted leading to a T-shape, whereas the SnCl3- unit is left almost unaltered. Molecular orbital and population analysis suggest that the emission of these tetrahedral Au1 complexes arises from a ³MC transition slightly perturbed by the SnCl3- fragment. [ABSTRACT FROM AUTHOR]

Heteronuclear complexes {[Hg(R)2][Au(R′)(PMe3)]2} n (R=R′=C6Cl2F3 ( 3); R=R′=C6F5 ( 4); R=C6Cl2F3, R′=C6F5 ( 5); R=C6F5, R′=C6Cl2F3 ( 6)) were prepared by the treatment of the corresponding organomercury compounds, [Hg(C6X5)2], with two equivalents of [Au(C6X5)(PMe3)]. Their crystal structures, as determined by using X-ray diffraction methods, display Au⋅⋅⋅Hg interactions. Although only compound 4 and 5 show luminescence in the solid state, all of these compounds quench the fluorescence of naphthalene in solution. Solution studies of these derivatives suggest a cooperative effect of the gold(I) center in switching on the quenching capabilities of the [Hg(C6X5)2] synthon with naphthalene. Theoretical studies confirmed the quenching ability of the organomercury species in the presence of gold. [ABSTRACT FROM AUTHOR]

Abstract: Model compounds are used to study the metallophilic attraction between gold and copper atoms. Ab initio calculations on dimers and tetramers in different distributions of the simplified units are analyzed. An attraction is found for all models and there is a reasonable agreement between the experimental and theoretical geometries. [ABSTRACT FROM AUTHOR]

Abstract: The (perhalophenyl)tin derivatives [SnR4] (1–3) and [SnR3Cl] (4–6) (R=C6F5, C6F3Cl2, C6Cl5) were prepared from SnCl4 and LiR or [SnR4] in the appropriate molar ratio, while the dinuclear complexes [SnR3]2 (7–9) were obtained by treatment of [SnR3Cl] with potassium under toluene reflux. Complexes 2, 6·0.5toluene and 7 were structurally characterized, the latter displaying a Sn–Sn bond of 2.808(7)Å, which indicates a strong tin–tin bond with covalent character in solid state. The hexaaryldistannanes 7–9 undergo transmetallation reactions with gold(I) derivatives, such as [AuCl(PPh3)] or [(AuCl)2(μ-dppm)], affording the neutral species [AuR(PPh3)] (10–12) or [(AuR)2(μ-dppm)] (13–15) or the ionic product [Au3Cl2(μ-dppm)2][Sn(C6F5)3Cl2] (16). The crystal structures of 14·CH2Cl2, 15 and 16·2CH2Cl2 were determined by X-ray diffraction, the latter showing a Au3 nearly equilateral triangular core in the cation with gold–gold contacts of 3.128(7) and 3.227(12)Å. The main difference between the molecular structures of 14·CH2Cl2 and 15 (both of them displaying intramolecular gold–gold contacts of 3.142(6) and 3.160(4)Å, respectively) is the presence of an intermolecular Au⋯Au interaction of 3.2126(8)Å in the case of the C6F3Cl2 complex that gives rise to a tetranuclear unit. [Copyright &y& Elsevier]

The gold(III) complex [Au(C6F5)2(SPNH2)JCIO4 (1) containing the S,N-donor ligand 2.(diphenylthiop hosphino)aniline (S=PNH2) can be easily prepared by treatment of S=PNH2with (Au(C6F5)2(OEt2)2]CIO4 and deprotonated with PPN(acac) to afford [Au(C6F5)2(SPNH)] (2). Complex 2 can also be obtained in a one-step reaction from SPNH2 and [Au(C6F5)2(acac)]. The electronic density in excess in 2 can be employed to incorporate a new metallic fragment to give the mixed complexes (Au(C6F5)2{S=PNH(MPPh3)}]CIO4 (M = Au (3), Ag (4)). The crystal structures of 1 and 2 have been determined by X-ray diffraction, showing that the electronic density in excess in complex 2 is located in the Au-N-C fragment. [ABSTRACT FROM AUTHOR]

Discusses the use of aurophilic and hydrogen bonding in the self-assembly of phosphine of diphosphine complexes of gold with the thiolate ligands derived from 2-thiobarbituric acid by deprotonation. Reaction of gold trifluoroacetate complexes; Synthesis and spectra of the complexes; Structure of the cyclic compound.

Reaction of perhalophenylgold(I) complexes [AuR(tht)] (R = C 6 Cl 2 F 3 , C 6 Cl 5 ; tht = tetrahydrothiophene) with different number of equivalents of Xantphos (4,5-Bis(diphenylphosphino)-9,9-dimethylxanthene) leads to discrete complexes in which the metal atom displays very different coordination environments. Thus, the ionic complex [Au(Xantphos) 2 [Au(C 6 Cl 2 F 3) 2 (1) or the neutral [Au(C 6 Cl 5)(Xantphos)] (2) one are obtained when a 1:1 (Au:Xantphos) stoichiometry is used. However, similar compounds [Au 2 R 2 (μ-Xantphos)] (R = C 6 Cl 2 F 3 (3); C 6 Cl 5 (4)) are synthesized when the amount of gold is increased to a 2:1 ratio. The use of diphosphine Xantphos, which can act as bridging, chelate or even as mono-dentate ligand, together with the use of different perhalophenyl groups bonded to the gold(I) centres, allows the synthesis of cationic tetracoordinate gold(I) fragments (1), mononuclear (2) or dinuclear (3 – 4) dicoordinated gold(I) complexes. This structural diversity in the coordination arrangements as well as the different aryl groups present in the molecules directly affect their photophysical properties, giving rise to different luminescent emission energies ranging from 470 to 580 nm, and also to a different origin for the electronic transitions related to them such as 3IL (3) to 3MLCT (4) and also a mixture of them 3MLCT/3IL (1 and 2). The experimental photophysical results obtained for these gold(I) complexes were supported by DFT and TD-DFT calculations. On the other hand, the behaviour of these complexes in solution is different, losing their emissive properties for all complexes or displaying the co-existence of different structural arrangements in the case of complexes 1 and 2 , as observed through variable-temperature 31P{1H} NMR experiments. Image 1 • The use of Xantphos expands the coordination abilities of gold(I) centres. • Controlling the structural arrangements permits a tuning of the emissive properties. • TD-DFT shows 3IL and/or 3MLCT transitions as responsible for the luminescence. [ABSTRACT FROM AUTHOR]

The calculated Au38 cluster is represented in the middle of the cover picture, coated by the N ‐ heterocyclic carbenes (NHCs) presented in the paper. The falling binary code “01” illustrates that the Au38 clusters are issued from DFT calculations. Molecular bis(NHC) gold complexes obtained from the functionalization of the particles are represented around the cluster. An experimental 1H NMR solid ‐ state spectrum is shown in the lower part of the cover to remind the reader that the study combines experimental and computational approaches. More information can be found in the Full Paper by F. Tielens, F. Remacle, S. Richeter et al. on page 10446 ff. [ABSTRACT FROM AUTHOR]

The cover picture shows a photograph of a gold–germanium complex that has two emission modes corresponding to two independent triplet excited states. The figure also shows the computed excited‐state structures of the two triplets, which display double Jahn–Teller distortions at the gold and germanium centres. The difference between the structures arises from a “T”‐shaped distortion at the gold centre with a different orientation depending on the triplet state. This small difference leads to a dramatic change of luminescence colour from orange to blue. Details are given in the Full Paper by José M. López‐de‐Luzuriaga et al. on page 176 in Issue 2, 2016 (DOI: 10.1002/cplu.201500337). [ABSTRACT FROM AUTHOR]

Investigates the chemical reaction between gold and thallium (Th) precursors. Synthesis of the gold-heterometal complex; Interaction of the Th atoms with the oxygen atom of an acetone; Linear coordination of the gold centers with pentachlorophenyl groups.

The first three-coordinate gold(I) N-heterocyclic carbene (NHC) complexes have been prepared with the nido-carborane diphosphine. The complexes are brightly luminescent and present very high quantum yield values. The carbene ligand is able to modulate the energy of the emissions and, depending upon the substituent, the luminescence changes from blue to green. Theoretical calculations corroborate that the emissions are phosphorescence and arise from charge transfer (LML'CT) transitions from nido-carborane ligand (L) to metal/ligand group "gold(I)-NHC ligand" (ML'). [ABSTRACT FROM AUTHOR]

Abstract: Model compounds are used to study the metallophilic attraction between gold and thallium atoms. Ab initio calculations on dimers and tetramers in different distributions of the minimal units are analyzed. An attraction is found for all models and there is a reasonable agreement between the experimental and theoretical geometries at the HF and MP2 levels. [Copyright &y& Elsevier]

Abstract: The heteropolynuclear complexes [AuTl(C6X5)2] n (X=F, Cl) react with dimethylsulfoxide (DMSO) in different molar ratios leading to products of stoichiometry [Tl2{Au(C6F5)2}2{μ-DMSO}3] n (1), and [Tl2{Au(C6Cl5)2}2{μ-DMSO}2] n (2). These complexes have been structurally characterized and can be viewed as extended linear chains built with Tl–Au–Tl units in which the thallium atoms are bridged by the oxygen atoms of DMSO ligands. Additional [Au(C6X5)2]− fragments interact with one or two thallium centres, respectively, giving rise to two different types of metal–metal interactions in each molecule. Both of them show a strong luminescence in solid state and complex 2 also in solution. The thallium–thallium interaction in this complex is considered to be the responsible of its luminescence, which remains in solution. [Copyright &y& Elsevier]

[AuTl(C6F5)2(en)] (en = ethylenediamine) reacts with cyclic ketones as cyclopentanone (Cy5＝O), cyclohexanone (Cy6＝O) or cycloheptanone (Cy7＝O) in 1:1 or 1:2 molar ratio leading to products of stoichiometry [AuTl(C6F5)2{CyxN(CH2)2NH2}] (x = 5 1, 6 2 or 7 3), or [AuTl(C6F5)2{Cyx＝N(CH2)2N＝Cyx}] (x = 5 4, 6 5 or 7 6). Addition of ethylenediamine to the ketimine complexes in chloroform regenerates [AuTl(C6F5)2(en)], the starting material, and the free ketimines, as their NMR and mass spectra evidenced. The ketimine complexes display luminescence in solid state at room temperature and at 77 K at higher wavelengths than the diamine starting product (505 nm). The excited states responsible for this behaviour are assigned to orbitals due to the gold–thallium interactions. [Copyright &y& Elsevier]

Examines the structure and synthesis of luminescent gold-thallium supramolecular arrays. Effect of donor properties changes in the assembly of atoms; Role of luminescence in the interaction of metal atoms; Nature of orbital involved in metal transitions.

This article reports that the main distortion for the phosphorescent excited state of a complex, prepared by the reaction between a gold (Au) precursor and a ligand in a 2:3 molar ratio, arises from a surprising Jahn-Teller distortion for only one of the gold centers together with a moderate Au-Au distance. Among the Au(I) compounds that show photoluminescence are those that exhibit planar three-coordination around the gold atom. The article authors wondered whether the Jahn-Teller excited-state distortion would occur in dinuclear three-coordinate Au(I) complexes in both metal centers, or instead, a decrease of the Au-Au distance would be produced as observed in dinuclear two-coordinate complexes.