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Article Cite This: ACS Omega 2019, 4, 7070−7075
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Synthesis of Trimetallic (HPd@M2Au8)3+ Superatoms (M = Ag, Cu) via Hydride-Mediated Regioselective Doping to (Pd@Au8)2+ Haru Hirai,† Shinjiro Takano,† and Tatsuya Tsukuda*,†,‡ †
Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Katsura, Kyoto 615-8520, Japan
‡
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S Supporting Information *
ABSTRACT: We have recently reported that hydride (H−) doped superatom (HPd@Au8)+ protected by eight PPh3 ligands selectively grew into (HPd@ Au10)3+ by the nucleophilic addition of two Au(I)Cl units. In the present study, (HPd@Au8)+ was successfully converted to unprecedented trimetallic (HPd@M2Au8)3+ superatoms (M = Ag, Cu) by controlled doping of two Ag(I)Cl or Cu(I)Cl units, respectively. Single-crystal X-ray diffraction analysis demonstrated that two Ag(I) or Cu(I) ions were regioselectively incorporated. Theoretical calculations suggested that hydrogens in (HPd@M2Au8)3+ (M = Au, Ag, Cu) occupy the same bridging site between the central Pd atom and the surface Au atom. (HPd@Ag2Au8)3+ exhibited photoluminescence at 775 nm, with the enhanced quantum yield of 0.09%, although it is structurally and electronically equivalent with (HPd@Au10)3+. This study demonstrates that hydride-mediated growth process is a promising atomically-precise bottom-up synthetic method of new multimetallic superatoms.
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is initiated by the activation of [Au 9 (PPh 3 ) 8 ] 3+ and [PdAu8(PPh3)8]2+ through doping of an H− anion to form [HAu9(PPh3)8]2+ and [HPdAu8(PPh3)8]+, respectively. This step is followed by sequential nucleophilic attack of the hydride-doped clusters to AuCl(PPh3) complex. The number of AuCl units incorporated into [Au11(PPh3)8Cl2]+ and [HPdAu10(PPh3)8Cl2]+ was limited to two because of the steric hindrance of the ligand layers. Hydride is released in the form of proton during the formation of [Au11(PPh3)8Cl2]+, whereas the H atom remained in 1 due to the high affinity of hydrogen to palladium.32,33 The aim of the present study is to apply the hydridemediated growth reaction for heterometal doping reaction. Unprecedented trimetallic clusters [HPdAg2Au8(PPh3)8Cl2]+ (2) and [HPdCu2Au8(PPh3)8Cl2]+ (3) were obtained by reacting the hydride-doped [HPdAu8(PPh3)8]+ with silver(I) and copper(I) complexes, AgCl(PPh3) and CuCl(PPh3), respectively. Single-crystal X-ray crystallography of 2 and 3 revealed that two MCl (M = Ag, Cu) units occupy the structurally equivalent sites. Theoretical calculations on model systems [HPdM2Au8(PMe3)8Cl2]+ (M = Ag, Cu) predicted the formation of superatomic cores (HPd@M2Au8)3+ in which the H atom is located at the bridging site of the central Pd and surface Au atoms. The core structure of 2 was quantitatively similar to that of 1, whereas that of 3 was slightly deformed due to the smaller size of Cu than that of Au and Ag.
INTRODUCTION Gold clusters protected by ligands have gained much interest as promising building units of functional nanoscale materials because of their size-specific properties.1−6 Recent progress in atomically precise synthesis has revealed that their physicochemical properties can be tuned dramatically not only by the number of constituent atoms of the core but also by doping foreign atoms.7−20 For instance, optical properties15,19 and catalytic activities7 of thiolate (RS) protected Au25(SR)18 cluster are modulated significantly by doping heterometal atoms. To establish the correlation between structure and functionalities of protected gold clusters, it is required to control precisely not only the chemical compositions but also the location of dopant atoms. Co-reduction of gold and dopant metal precursor ions has been used frequently as a straightforward method to synthesize doped gold clusters. However, it is still a challenge to obtain the doped clusters with the desired composition in high yield due to the difference in the relative reduction rates of the precursor metal ions. To circumvent the difficulties, other methods such as galvanic and antigalvanic methods have been developed.12,13,17,19,21−23 Tri- and tetrametallic clusters have been synthesized by antigalvanic processes between preformed bimetallic clusters and heterometal complexes24−26 and reduction of heterometal precursors in the presence of preformed bimetallic clusters.27−30 Recently, we reported controlled growth of phosphineprotected oblate gold-based clusters, [Au9(PPh3)8]3+ and [PdAu8(PPh3)8]2+, to spherical clusters, [Au11(PPh3)8Cl2]+ and [HPdAu10(PPh3)8Cl2]+ (1), respectively.31−33 This growth © 2019 American Chemical Society
Received: February 28, 2019 Accepted: April 8, 2019 Published: April 18, 2019 7070
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mixtures showed that the incorporation of two MCl units (M = Ag, Cu) was completed within 2 h, much faster than that of AuCl units (∼4 h). The 31P{1H} NMR chart for 2 (Figure 1c) exhibits a triplet signal, indicating that eight phosphorus nuclei of the PPh3 ligands couple with two silver atoms equivalently on the NMR time scale. The average coupling constant 3 31 J( P−Ag) was 19.6 Hz, whereas the coupling constant of 31 P−105Ag and 31P−107Ag could not be determined. Although [HPdAgAu9(PPh3)8Cl2]+ (2′) and [HPdCuAu9(PPh3)8Cl2]+ (3′) were detected as byproducts in the ESI mass spectra (Figure 1a,b), the 31P{1H} NMR charts suggest that their actual populations are smaller than expected from the relative intensities of the mass peaks: no peak assignable to 2′ was observed in Figure 1c, and the population of 3′ is less than 15% from Figure 1d. To confirm that the doping of hydride (H − ) to [PdAu8(PPh3)8]2+ is indispensable for the doping of Ag or Cu (eqs 1 and 2), we monitored the reactions between [PdAu8(PPh3)8]2+ and MCl(PPh3) (M = Ag, Cu) (for details, see the Supporting Information). The ESI mass spectrometry (ESI-MS) showed that the peak intensity of [PdAu8(PPh3)8]2+ drastically decreased just after the addition of MCl(PPh3) and that a new peak of [Au(PPh3)2]+ appeared (Figure S2). Formation of 2 or 3 was not observed even after 2 h by ESIMS and ultraviolet−visible (UV−vis) absorption spectroscopy (Figure S3). These results indicate that [PdAu8(PPh3)8]2+ does not undergo nucleophilic attack to MCl(PPh3) without predoping of H−. We also examined whether 2 and 3 are produced by the coreduction of metal precursors, since the synthesis of 1 by the co-reduction method was reported previously.34 The mixture of Pd(PPh3)4, AuCl(PPh3), and MCl(PPh3) with a molar ratio of 1:8:3 was reduced by sodium borohydride in EtOH (for details, see the Supporting Information). ESI-MS of the products (Figure S4) showed that 2 was formed as a minor species when M = Ag, whereas 3 was not generated when M = Cu. Therefore, the simple co-reduction method is not efficient for the synthesis of trimetallic clusters 2 and 3, whereas the hydride-mediated doping processes via eqs 1 and 2 are an effective method. Figure 2a,c represents the geometric structures of 2 and 3, respectively, determined by single-crystal X-ray diffraction (SCXRD) analysis. In both clusters, Pd atom occupies the central position and two MCl units are incorporated at the surface to form nearly spherical superatomic cores, as in the case of [HPdAu10(PPh3 ) 8Cl2] + (1) (Figure S5). The occupancy of Cu in the core (1.68/2.00) of 3 was consistent with the purity estimated from the 31P{1H} NMR chart (Figure 1d). However, the position of the doped H atom could not be determined by SCXRD analysis because of its weak scattering power. Figure 2a,c shows that one of the Au−Au surface bonds of 2 (3.89 Å) or 3 (3.91 Å) was significantly longer than the corresponding Au−Au bond in [Au11(PPh3)8Cl2]+ (3.11 Å).35 This deformation of the core was also observed in 1 and is ascribed to the location of H atom near the central Pd atom.32 To identify the location of the “invisible” H atom in 2 and 3, density functional theory (DFT) calculation was conducted on the model systems [HPdAg2Au8(PMe3)8Cl2]+ (2m) and [HPdCu2Au8(PMe3)8Cl2]+ (3m) using the B3LYP functional. Basis sets used were LanL2dz and 6-31G(d) for metal atoms and others, respectively. Two isomers (2m-a and 2m-b) and (3m-a and 3m-b) with comparable stability were obtained as
Nevertheless, 1−3 exhibited similar optical spectra in the onset region, indicating that the replacement of two coinage atoms in (HPd@M2Au8)3+ does not affect the superatomic orbitals. The doped superatoms (HPd@M2Au8)3+ (M = Ag, Cu) showed photoluminescence (PL), whereas the undoped (HPd@ Au10)3+ did not. This study not only provides new superatoms but also demonstrates that hydride-mediated process is a promising atomically precise bottom-up method to synthesize multielement superatoms.
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RESULTS AND DISCUSSION Doping of Ag or Cu was conducted by adding a dichloromethane (DCM) solution of 3 equiv of AgCl(PPh3) or CuCl(PPh3) to an ethanol−tetrahydrofuran (EtOH−THF) solution of [HPdAu8(PPh3)8]+ that was prepared following the reported method.32 Electrospray ionization (ESI) mass spectra of the reaction mixtures indicated that the main products were
Figure 1. Positive-ion ESI mass spectra of (a) 2 and (b) 3. Insets compare the experimental and theoretical isotope patterns. 2′ and 3′ are assigned to [HPdAgAu9(PPh3)8Cl2]+ and [HPdCuAu9(PPh3)8Cl2]+, respectively. 31P{1H} NMR charts (162 MHz, CD2Cl2, 298 K) of (c) 2 and (d) 3.
2 and 3, respectively (Figure 1a,b). Thus, the doping reactions are expressed as follows [HPdAu8(PPh3)8 ]+ + 2AgCl(PPh3) → [HPdAg 2Au8(PPh3)8 Cl 2]+ (2) + 2PPh3
(1)
[HPdAu8(PPh3)8 ]+ + 2CuCl(PPh3) → [HPdCu 2Au8(PPh3)8 Cl 2]+ (3) + 2PPh3
(2)
In situ Ag K-edge X-ray absorption near-edge structure analysis during eq 1 showed that the spectral feature of Ag(I) disappeared and the metallic feature appeared within 20 min (Figure S1). Thin-layer chromatography (TLC) of the reaction 7071
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1, 2, and 3, indicating that the introduction of two MCl units proceeded regioselectively regardless of M. The occupancy analysis of Au and M in 2 and 3 showed that M dopants are always bonded to the Cl ligands without any scrambling with Au atoms. These results suggest that 1 has two identical preferential doping sites regardless of M. The occupation of identical sites by four MCl units (M = Au, Ag, Cu) was also reported in [Au9M4(PR3)8Cl4]+.36 These doping modes are in sharp contrast to that found in doping to [Au25(SR)18]− where Ag and Cu dopants occupy different sites.37,38 The number and location of the doped MCl units are probably determined by the packing structure of the ligand layer. Although the crystal structures of 1, 2, and 3 were similar, the bond lengths around the MCl units varied depending on the doped metals. The distributions of the bond lengths between the M atom and the adjacent Au and Pd atoms are shown by the histograms in Figure 3b. The histograms indicate that the Cu−Au/Pd bonds of 3 are shorter than the corresponding Ag− and Au−Au/Pd bonds of 1 and 2, respectively. The shortening of the Cu− metal bonds of 3 is consistent with the smaller van der Waals radius of Cu compared to those of Au and Ag (Au: 1.66 Å, Ag: 1.72 Å, Cu: 1.40 Å). In contrast, the other metal−metal bond lengths hardly vary (Figure S6). The cores of the reaction products 1−3, (HPd@M2Au8)3+ (M = Ag, Ag, Cu), and the precursor, (HPd@Au8)+, are all viewed as electronically closed superatoms with an electronic configuration of (1S)2(1P)6. This simple picture is supported by optical spectroscopy. Figure 3c demonstrates that the spectral profiles of 1−3 and [HPdAu8(PPh3)8]+ are similar in the wavelength region of >400 nm: a broad band with an optical onset in the range of 600−700 nm. This observation suggests that the electronic structures of (HPd@M2Au8)3+ (M = Au, Ag, Cu) and (HPd@Au8)+ are similar, since the optical absorption in the onset region is governed by optical transitions that involve occupied 1P and unoccupied 1D orbitals. The similarity of electronic structures of 1−3 is confirmed by those calculated for the corresponding model systems, 1m,32 2m-a, and 3m-a. Figure S7 shows that the energy gaps between the 1P and 1D orbitals are comparable, although the 1P orbitals of 2m-a and 3m-a are less degenerated than those of 1m. Two features are discernible from the natural population analysis of 1m, 2m-a, and 3m-a (Figure S8). First, the natural bond orbitals (NBOs) charges on Ag and Cu dopants are larger than those of the corresponding Au atoms, indicating that the charge distribution in superatomic cores are affected by doping. Second, the NBO charge on both the H and peripheral Au atoms is almost neutral, indicating that the H atom contributes its 1s electron to the superatomic electron count. These results indicate that the superatomic orbitals of (HPd@M2 Au8) 3+ are not appreciably affected by the dopant M, although the geometric structure and charge distribution are slightly affected. In contrast, the spectral profile of 3 is significantly different from those of 1 and 2 in the wavelength region of Cu > Au. This study illustrates the general scope of the chemical reactivity of hydride-doped superatom and will provide a novel bottom-up, atomically precise synthesis of novel multimetallic superatoms.
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EXPERIMENTAL SECTION Chemicals. Chloroauric acid tetrahydrate was purchased from Tanaka Precious Metals. Solvents, triphenylphosphine, tetrakis(triphenylphosphine)palladium(0), silver nitrate, copper chloride dihydrate, potassium chloride, and sodium borohydride were purchased from Wako Pure Chemical Industries. THF (dehydrated) was purchased from Kanto Chemicals. The water used was Milli-Q grade (>18 MΩ). All commercially available reagents were used as received. Au(PPh3)(NO3) (ref 39) was synthesized from AuCl(PPh3) obtained from chloroauric acid tetrahydrate.40 AgCl(PPh3) and CuCl(PPh3) were synthesized from silver nitrate and copper chloride dihydrate, respectively.41 [PdAu8(PPh3)8](NO 3)2 and [HPdAu10(PPh3 )Cl2](Cl, NO 3) (1) were synthesized according to the literature.32 General. 1H (400 MHz) and 31P{1H} (162 MHz) NMR charts were recorded on a JEOL JNM-ECS400 spectrometer. All NMR experiments were conducted at 298 K. Chemical shifts in the 1H NMR charts were referenced to the residual proton signal of the solvent (CD2Cl2: δ 5.32). Chemical shifts
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ASSOCIATED CONTENT
S Supporting Information *
The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acsomega.9b00575. Experimental details and data; Ag K-edge X-ray absorption near-edge structure spectra; in situ positive7073
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(13) Wang, S.; Li, Q.; Kang, X.; Zhu, M. Customizing the Structure, Composition, and Properties of Alloy Nanoclusters by Metal Exchange. Acc. Chem. Res. 2018, 51, 2784−2792. (14) Tang, Q.; Hu, G.; Fung, V.; Jiang, D.-E. Insights into Interfaces, Stability, Electronic Structure, and Catalytic Activities of Atomically Precise Metal Nanoclusters form First Principles. Acc. Chem. Res. 2018, 51, 2793−2802. (15) Aikens, C. M. Electronic and Geometric Structure, Optical Properties, and Excited State Behavior in Atomically Precise ThiolateStabilized Nobel Metal Nanoclusters. Acc. Chem. Res. 2018, 51, 3065−3073. (16) Yan, J.; Teo, B. K.; Zheng, N. Surface Chemistry of Atomically Precise Coinage-Metal Nanoclusters: From Structural Control to Surface Reactivity and Catalysis. Acc. Chem. Res. 2018, 51, 3084− 3093. (17) Ghosh, A.; Mohammed, O. F.; Bakr, O. M. Atomic-Level Doping of Metal Clusters. Acc. Chem. Res. 2018, 51, 3094−3103. (18) Bhattarai, B.; Zaker, Y.; Atnagulov, A.; Yoon, B.; Landman, U.; Bigioni, T. P. Chemistry and Structure of Silver Molecular Nanoparticles. Acc. Chem. Res. 2018, 51, 3104−3113. (19) Hossain, S.; Niihori, Y.; Nair, L. V.; Kumar, B.; Kurashige, W.; Negishi, Y. Alloy Clusters: Precise Synthesis and Mixing Effects. Acc. Chem. Res. 2018, 51, 3114−3124. (20) Kwak, K.; Lee, D. Electrochemistry of Atomically Precise Metal Nanoclusters. Acc. Chem. Res. 2019, 52, 12−22. (21) Wu, Z. Anti-Ganlvanic Reduction of Thiolate-Protected Gold and Silver Nanoparticles. Angew. Chem., Int. Ed. 2012, 51, 2934− 2938. (22) Wang, M.; Wu, Z.; Chu, Z.; Yang, J.; Yao, C. Chemico-Physical Synthesis of Surfactant- and Ligand-Free Gold Nanoparticles and Their Anti-Galvanic Reduction Property. Chem. - Asian J. 2014, 9, 1006−1010. (23) Yao, C.; Chen, J.; Li, M.-B.; Liu, L.; Yang, J.; Wu, Z. Adding Two Active Silver Atoms on Au25 Nanoparticle. Nano Lett. 2015, 15, 1281−1287. (24) Bootharaju, M. S.; Sinatra, L.; Bakr, O. M. Distinct MetalExchange Pathways of Doped Ag25 Nanoclusters. Nanoscale 2016, 8, 17333−17339. (25) Yan, N.; Liao, L.; Yuan, J.; Lin, Y.-J.; Weng, L.-H.; Yang, J.; Wu, Z. Bimetal Doping in Nanoclusters: Synergetic or Counteractive? Chem. Mater. 2016, 28, 8240−8247. (26) Sharma, S.; Yamazoe, S.; Ono, T.; Kurashige, W.; Niihori, Y.; Nobusada, K.; Tsukuda, T.; Negishi, Y. Tuning the Electronic Structure of Thiolate-Protected 25-Atom Clusters by Co-Substitution with Metals Having Different Preferential Site. Dalton Trans. 2016, 45, 18064−18068. (27) Teo, B. K.; Zhang, H.; Shi, X. Site Preference in Vertex-Sharing Polyicosahedral Supraclusters Containing Groups 10 and 11 Metals and Their Bonding Implications: Synthesis and Structures of the First Au-Ag-M (M = Pt, Ni) Biicosahedral Clusters [(Ph3P)10Au12Ag12PtCl7]Cl and [(Ph3P)10Au12Ag12NiCl7](SbF6). Inorg. Chem. 1994, 33, 4086−4097. (28) Kappen, T. G. M. M.; Schlebos, P. P. J.; Bour, J. J.; Bosman, W. P.; Beurskens, G.; Smits, J. M. M.; Beurskens, P. T.; Steggerda, J. J. Cluster Growth: Some Representative Reactions. Crystal Structures of [Pt(H)(AgNO3)(AuPPh3)8](NO3) and [Pt(H)(AgNO3)2(AuPPh3)8](NO3). Inorg. Chem. 1995, 34, 2121−2132. (29) Kappen, T. G. M. M.; Schlebos, P. P. J.; Bour, J. J.; Bosman, W. P.; Smits, J. M. M.; Beurskens, P. T.; Steggerda, J. J. New HydrideContaining Mixed Metal-Gold Phosphine Clusters. Crystal Structures of [Pt(H)(CuCl)(AuPPh3)8](NO3) and [Pt(H)(CuCl)2(AuPPh3)8](NO3). Inorg. Chem. 1995, 34, 2133−2142. (30) Teo, B. K.; Zhang, H. Synthesis and Structure of a Neutral Trimetallic Biicosahedral Cluster, (Ph3P)10Au11Ag12Pt2Cl7. A Comparative Study of Molecular and Crystal Structures of Vertex-Sharing Biicosahedral Mixed-Metal Nanoclusters. J. Cluster Sci. 2001, 12, 349−383.
ion ESI-MS spectra during the reaction; SCXRD structures; lengths of the Au−Au bonds; calculated energy diagrams; NBO charges of the individual atoms (PDF) Crystallography data (CIF) (CIF)
AUTHOR INFORMATION
Corresponding Author
*E-mail:
[email protected]. ORCID
Shinjiro Takano: 0000-0001-9262-5283 Tatsuya Tsukuda: 0000-0002-0190-6379 Notes
The authors declare no competing financial interest.
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ACKNOWLEDGMENTS This research was financially supported by the Elements Strategy Initiative for Catalysts & Batteries (ESICB) and by the “Nanotechnology Platform” (Project No. 12024046) of the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan and a Grant-in-Aid for Scientific Research (A) (Grant No. 17H01182) from the Japan Society for the Promotion of Science (JSPS). The synchrotron radiation experiments were performed with the approval of the Japan Synchrotron radiation Research Institute (JASRI) (Proposal Nos. 2018A1055 and 2018B1123).
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REFERENCES
(1) Pignolet, L. H.; Aubart, M. A.; Craighead, K. L.; Gould, R. A. T.; Krogstad, S. A.; Wiley, J. S. Phosphine-Stabilized, Platinum-Gold and Palladium−Gold Cluster Compounds and Applications in Catalysis. Coord. Chem. Rev. 1995, 143, 219−263. (2) Tsukuda, T. Towards an Atomic-Level Understanding of SizeSpecific Properties of Protected and Stabilized Gold Clusters. Bull. Chem. Soc. Jpn. 2012, 85, 151−168. (3) Konishi, K. Phosphine-Coordinated Pure-Gold Clusters: Diverse Geometrical Structures and Unique Optical Properties/Responses. Struct. Bonding 2014, 161, 49−86. (4) Tsukuda, T.; Häkkinen, H. Protected Metal Clusters: From Fundamental to Applications, 1st ed.; Elsevier, B.V.: Amsterdam, The Netherlands, 2015. (5) Jin, R.; Zeng, C.; Zhou, M.; Chen, Y. Atomically Precise Colloidal Nanoclusters and Nanoparticles: Fundamentals and Opportunities. Chem. Rev. 2016, 116, 10346−10413. (6) Chakraborty, I.; Pradeep, T. Atomically Precise Clusters of Noble Metals: Emerging Link between Atoms and Nanoparticles. Chem. Rev. 2017, 117, 8208−8271. (7) Zhao, J.; Jin, R. Heterogeneous Catalysis by Gold-Based Bimetal Nanoclusters. Nano Today 2018, 18, 86−102. (8) Yao, Q.; Chen, T.; Yuan, X.; Xie, J. Towards Total Synthesis of Thiolate-Protected Metal Nanoclusters. Acc. Chem. Res. 2018, 51, 1338−1348. (9) Lei, Z.; Wan, X.-K.; Yuan, S.-F.; Guan, Z.-J.; Wang, Q.-M. Alkynyl Approach toward the Protection of Metal Nanoclusters. Acc. Chem. Res. 2018, 51, 2465−2474. (10) Sharma, S.; Chakrahari, K. K.; Saillard, J.-Y.; Liu, C. W. Structurally Precise Dichalcogenolate-Protected Copper and Silver Superatomic Nanoclusters and Their Alloys. Acc. Chem. Res. 2018, 51, 2475−2483. (11) Higaki, T.; Li, Q.; Zhou, M.; Zhao, S.; Li, Y.; Li, S.; Jin, R. Towards the Tailoring Chemistry of Metal Nanoclusters for Enhancing Functionalities. Acc. Chem. Res. 2018, 51, 2764−2773. (12) Gan, Z.; Xia, N.; Wu, Z. Discovery, Mechanism, and Application of Antigalvanic Reaction. Acc. Chem. Res. 2018, 51, 2774−2783. 7074
DOI: 10.1021/acsomega.9b00575 ACS Omega 2019, 4, 7070−7075
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Article
(31) Takano, S.; Hirai, H.; Muramatsu, S.; Tsukuda, T. HydrideDoped Gold Superatom (Au9H)2+: Synthesis, Structure and Transformation. J. Am. Chem. Soc. 2018, 140, 8380−8383. (32) Takano, S.; Hirai, H.; Muramatsu, S.; Tsukuda, T. HydrideMediated Controlled Growth of a (Pd@Au8)2+ Superatom to a Hydride-Doped (HPd@Au10)3+ Superatom. J. Am. Chem. Soc. 2018, 140, 12314−12317. (33) Takano, S.; Hasegawa, S.; Suyama, M.; Tsukuda, T. Hydride Doping Chemically-Modified Gold-Based Superatoms. Acc. Chem. Res. 2018, 51, 3074−3083. (34) Kurashige, W.; Negishi, Y. Synthesis, Stability, and Photoluminescence Properties of PdAu10(PPh3)8Cl2 Clusters. J. Cluster Sci. 2012, 23, 365−374. (35) McKenzie, L. C.; Zaikova, T. O.; Hutchison, J. E. Structurally Similar Triphenylphosphine-Stabilized Undecagolds, Au11(PPh3)3Cl3 and [Au11(PPh3)8Cl2]Cl, Exhibit Distinct Ligand Exchange Pathways with Glutathione. J. Am. Chem. Soc. 2014, 136, 13426−13435. (36) Copley, R. C. B.; Mingos, D. M. P. Synthesis and Characterization of the Centred Icosahedral Cluster Series [Au9M4IBCl4(PMePh2)8][C2B9H12], where MIB= Au, Ag, or Cu. J. Chem. Soc., Dalton Trans. 1996, 491−500. (37) Kumara, C.; Aikens, C. M.; Dass, A. X-ray Crystal Structure and Theoretical Analysis of Au25−xAgx(SCH2Ph)18− Alloy. J. Phys. Chem. Lett. 2014, 5, 461−466. (38) Yamazoe, S.; Kurashige, W.; Nobusada, K.; Negishi, Y.; Tsukuda, T. Preferential Location of Coinage Metal Dopants (M = Ag or Cu) in [Au25−xMx(SCH2Ph)18]− (x ∼ 1) As Determined by Extended X-ray Absorption Fine Structure and Density Functional Theory Calculations. J. Phys. Chem. C 2014, 118, 25284−25290. (39) Mueting, A. M.; Alexander, B. D.; Boyle, P. D.; Casalnuovo, A. L.; Ito, L. N.; Johnson, B. J.; Pignolet, L. H.; et al. Mixed-Metal-Gold Phosphine Cluster Compounds. Inorg. Synth. 1992, 29, 279−298. (40) Gregory, B. J.; Ingold, C. K. Mechanism of Electronic Substitution at a Saturated Carbon Atom. Part XI. Bimolecular and Unimolecular Substitution of Mercury for Gold in Alkylgold Complexes. J. Chem. Soc. B 1969, 276−289. (41) Halim, M.; Kennedy, R. D.; Suzuki, M.; Khan, S. I.; Diaconescu, P. L.; Rubin, Y. Complexes of Gold(I), Silver(I), and Copper(I) with Pentaaryl[60]fullerides. J. Am. Chem. Soc. 2011, 133, 6841−6851. (42) Strohalm, M.; Kavan, D.; Novák, P.; Volný, M.; Havlíček, V. mMass 3: A Cross-Platform Software Environment for Precise Analysis of Mass Spectrometric Data. Anal. Chem. 2010, 82, 4648− 4651. (43) Weber, G.; Teale, F. W. J. Determination of the Absolute Quantum Yield of Fluorescent Solutions. Trans. Faraday Soc. 1957, 53, 646−655.
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