Abstract
Small gold clusters with diameters less than or equal to 2 nm (below approximately 200 atoms) possess geometric and electronic structures different from bulk gold. When these gold clusters are protected by ligands, these clusters can be treated as chemical compounds. This review focuses on gold clusters protected by chalcogenate (thiolate, selenolate, or tellurolate) ligands and describes the methods by which these clusters are synthesized as well as their geometric/electronic structures and physical and chemical properties. Recent findings regarding ligand exchange reactions, which may be used to impart functionality to these compounds, are also described.
Keywords
- gold clusters
- chalcogenate
- geometric and electronic structures
- physical and chemical properties
- ligand exchange reactions
1. Introduction
Small gold clusters with diameters less than or equal to 2 nm (below approximately 200 atoms) possess geometric and electronic structures different from those of bulk gold [1]. The geometric structure often consists of an atomic arrangement, such as an icosahedral structure, that differs from the close-packed structure of bulk gold, as a result of reducing the surface energy. In addition, a discrete electronic structure appears rather than the continuous structure observed in the bulk element. Owing to these characteristics, small gold clusters exhibit fundamental properties and functionalities different from those of bulk gold. In addition, when these gold clusters are protected by ligands, it is possible to treat them as chemical compounds. In early studies, beginning in the 1960s, phosphine was employed as a protective ligand [2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]. Representative phosphine (PR3)-protected gold clusters (Au
2. Synthesis of Aun (XR)m clusters
The method used most frequently to synthesize Au
The product obtained from this technique is typically a mixture of Au
3. Geometrical structures of Aun (XR)m clusters
Until 2007, it was believed that Au
4. Electronic structures of Aun (XR)m clusters
Unlike bulk gold, small Au
At present, the relationship between cluster size and electronic structure is not well understood for Au
5. Physical and chemical properties of Aun (XR)m clusters
Au
5.1. Photoluminescence
Small Au
5.2. Redox behavior
Au
5.3. Optical activity
Several clusters, such as Au38(SR)24 and Au40(SR)24, have optical isomers with different ─S(R)[─Au─S(R)]
5.4. Catalytic activity
Catalytic activity is another typical size-specific property of Au
5.5. Effect of changing ligands
Regarding Au
6. Ligand exchange reactions
As described above, Au
6.1. Mechanism
Murray et al. reported the ligand exchange reactions of this type of cluster nearly 20 years ago [60, 61, 62, 63, 64, 65]. However, their research was conducted using mixtures and did not use advanced techniques such as mass spectrometry and single-crystal X-ray structural analysis to characterize the products. Therefore, a thorough understanding of the details of these reactions was not obtained. More recent research has elucidated the associated mechanism. As an example, Au25(SR)18 has a geometry in which the Au13 core is covered by six ─S(R)─[Au─S(R)]2─ staples (Figure 9(a)). As a result, there are two types of SR units in Au25(SR)18: those in contact with the Au13 core (core-site SR; Figure 9(a)) and those at the apex of each staple (apex-site SR; Figure 9(a)) [102, 103]. Ackerson et al. performed a single-crystal X-ray structural analysis of the product obtained from the reaction of Au25(SC2H4Ph)18 (SC2H4Ph = 2-phenyl ethanethiolate) with
6.2. Induction of quasi-isomerization
Studies have found that, in addition to ligand exchange, a change in geometry can also take place during reactions with thiol (RSH) (Figure 8(b)). This discovery originated from the prediction of the geometry of Au24(SR)20 clusters. Specifically, Jin et al. synthesized Au24(SC2H4Ph)20 in 2010 [107], after which Pei and coworkers predicted the geometry of these clusters via DFT calculations based on Au24(SCH3)20 [108]. Thereafter, Jin et al. characterized Au24(SCH2Ph-
6.3. Induction of size transformation
Researches have also shown that the introduction of a significant structural deformation via ligand exchange can result in the formation of Au
6.4. Relation between ligand structure and outcome
In this way, the outcomes are significantly affected by the bulkiness of the ligand in the ligand exchange reactions. Normally, ligand exchange with alkanethiol or PhC2H4SH does not result in structural transformation, but simply leads to ligand exchange. Conversely, a bulky ligand such as
7. Summary
This chapter summarized common methods of fabricating Au
Acknowledgments
This work was partly supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (grant numbers JP16H04099, 16 K17480, and 17 K19040) and by the Scientific Research on Innovative Areas (Coordination Asymmetry) (grant number 17H05385). Funding from the Takahashi Industrial and Economic Research Foundation, Futaba Electronics Memorial Foundation, Iwatani Naoji Foundation, Murata Science Foundation, and Ube Industries Foundation is also gratefully acknowledged. We thank Michael D. Judge, MSc, from Edanz Group (www.edanzediting.com/ac) for editing a draft of this manuscript.
References
- 1.
Corain B, Schmid G, Toshima N, editors. Metal Nanoclusters in Catalysis and Materials Science: The Issue of Size Control. 1st ed. Amsterdam: Elsevier; 2007. 470 p - 2.
McKenzie LC, Zaikova TO, Hutchison JE. Structurally similar triphenylphosphine-stabilized undecagolds, Au11(PPh3)7Cl3 and [Au11(PPh3)8Cl2]Cl, exhibit distinct ligand exchange pathways with glutathione. Journal of the American Chemical Society. 2014; 136 :13426-13435. DOI: 10.1021/ja5075689 - 3.
Vollenbroek FA, Bour J, Velden JWA. Gold-phosphine cluster compounds. The reactions of [Au9L8]3+ (L = PPh3) with L, SCN− and Cl− to [Au8L8]2+ (Au11L8(SCN)2]+ and [Au11L8Cl2]+. Recueil des Travaux Chimiques des Pays-Bas. 1980; 99 :137-141. DOI: 10.1002/recl.19800990410 - 4.
Schulz-Dobrick M, Jansen M. Characterization of gold clusters by crystallization with polyoxometalates: The intercluster compounds [Au9(dpph)4][Mo8O26], [Au9(dpph)4][PW12O40] and [Au11(PPh3)8Cl2]2[W6O19]. Zeitschrift für anorganische und allgemeine Chemie. 2007; 633 :2326-2331. DOI: 10.1002/zaac.200700210 - 5.
Woehrle GH, Warner MG, Hutchison JE. Ligand exchange reactions yield subnanometer, thiol-stabilized gold particles with defined optical transitions. The Journal of Physical Chemistry B. 2002; 106 :9979-9981. DOI: 10.1021/jp025943s - 6.
Yang Y, Chen S. Surface manipulation of the electronic energy of subnanometer-sized gold clusters: An electrochemical and spectroscopic investigation. Nano Letters. 2003; 3 :75-79. DOI: 10.1021/nl025809j - 7.
Shichibu Y, Negishi Y, Tsukuda T, Teranishi T. Large-scale synthesis of thiolated Au25 clusters via ligand exchange reactions of phosphine-stabilized Au11 clusters. Journal of the American Chemical Society. 2005; 127 :13464-13465. DOI: 10.1021/ja053915s - 8.
Liu Y, Tsunoyama H, Akita T, Tsukuda T. Preparation of ~1 nm gold clusters confined within mesoporous silica and microwave-assisted catalytic application for alcohol oxidation. The Journal of Physical Chemistry C. 2009; 113 :13457-13461. DOI: 10.1021/jp904700p - 9.
Walter M, Akola J, Lopez-Acevedo O, Jadzinsky PD, Calero G, Ackerson CJ, Whetten RL, Grönbeck H, Häkkinen H. A unified view of ligand-protected gold clusters as superatom complexes. Proceedings of the National Academy of Sciences of the United States of America. 2008; 105 :9157-9162. DOI: 10.1073/pnas.0801001105 - 10.
Briant CE, Theobald BRC, White JW, Bell LK, Mingos DMP, Welch AJ. Synthesis and X-ray structural characterization of the centred icosahedral gold cluster compound [Aul3(PMe2Ph)10Cl2](PF6)3; the realization of a theoretical prediction. Journal of the Chemical Society, Chemical Communications. 1981:201-202. DOI: 10.1039/C39810000201 - 11.
Teo B, Shi X, Zhang H. Pure gold cluster of 1:9:9:1:9:9:1 layered structure: A novel 39-metal-atom cluster [(Ph3P)14Au39Cl6]Cl2 with an interstitial gold atom in a hexagonal antiprismatic cage. Journal of the American Chemical Society. 1992; 114 :2743-2745. DOI: 10.1021/ja00033a073 - 12.
Schmid G, Pfeil R, Boese R, Bandermann F, Meyer S, Calis GHM, Velden JWA. Au55[P(C6H5)3]12CI6 - a gold cluster of an exceptional size. Chemische Berichte-Recueil. 1981; 114 :3634-3642. DOI: 10.1002/cber.19811141116 - 13.
Schmid G. Large clusters and colloids. Metals in the embryonic state. Chemical Reviews. 1992; 92 :1709-1727. DOI: 10.1021/cr00016a002 - 14.
Boyen HG, Kästle G, Weigl F, Koslowski B, Dietrich C, Ziemann P, Spatz JP, Riethmüller S, Hartmann C, Möller M, Schmid G, Garnier MG, Oelhafen P. Oxidation-resistant gold-55 clusters. Science. 2002; 297 :1533-1536. DOI: 10.1126/science.1076248 - 15.
Inomata T, Konishi K. Gold nanocluster confined within a cage: Template-directed formation of a hexaporphyrin cage and its confinement capability. Chemical Communications. 2003:1282-1283. DOI: 10.1039/B302609D - 16.
Balasubramanian R, Guo R, Mills AJ, Murray RW. Reaction of Au55(PPh3)12Cl6 with thiols yields thiolate monolayer protected Au75 clusters. Journal of the American Chemical Society. 2005; 127 :8126-8132. DOI: 10.1021/ja050793v - 17.
Brust M, Walker M, Bethell D, Schiffrin DJ, Whyman R. Synthesis of thiol-derivatised gold nanoparticles in a two-phase liquid–liquid system. Journal of the Chemical Society, Chemical Communications. 1994:801-802. DOI: 10.1039/C39940000801 - 18.
Tsukuda T. Toward an atomic-level understanding of size-specific properties of protected and stabilized gold clusters. Bulletin of the Chemical Society of Japan. 2012; 85 :151-168. DOI: 10.1246/bcsj.20110227 - 19.
Whetten RL, Shafigullin MN, Khoury JT, Schaaff TG, Vezmar I, Alvarez MM, Wilkinson A. Crystal structures of molecular gold nanocrystal arrays. Accounts of Chemical Research. 1999; 32 :397-406. DOI: 10.1021/ar970239t - 20.
Parker JF, Fields-Zinna CA, Murray RW. The story of a monodisperse gold nanoparticle: Au25L18. Accounts of Chemical Research. 2010; 43 :1289-1296. DOI: 10.1021/ar100048c - 21.
Murray RW. Nanoelectrochemistry: Metal nanoparticles, nanoelectrodes, and nanopores. Chemical Reviews. 2008; 108 :2688-2720. DOI: 10.1021/cr068077e - 22.
Li G, Jin R. Atomically precise gold nanoclusters as new model catalysts. Accounts of Chemical Research. 2013; 46 :1749-1758. DOI: 10.1021/ar300213z - 23.
Qian H, Zhu M, Wu Z, Jin R. Quantum sized gold nanoclusters with atomic precision. Accounts of Chemical Research. 2012; 45 :1470-1479. DOI: 10.1021/ar200331z - 24.
Dass A. Nano-scaling law: Geometric foundation of thiolated gold nanomolecules. Nanoscale. 2012; 4 :2260-2263. DOI: 10.1039/c2nr11749e - 25.
Negishi Y, Kurashige W, Niihori Y, Nobusada K. Toward the creation of stable, functionalized metal clusters. Physical Chemistry Chemical Physics. 2013; 15 :18736-18751. DOI: 10.1039/c3cp52837e - 26.
Negishi Y. Toward the creation of functionalized metal nanoclusters and highly active photocatalytic materials using thiolate-protected magic gold clusters. Bulletin of the Chemical Society of Japan. 2014; 87 :375-389. DOI: 10.1246/bcsj.20130288 - 27.
Luo Z, Nachammai V, Zhang B, Yan N, Leong DT, Jiang DE, Xie J. Toward understanding the growth mechanism: Tracing all stable intermediate species from reduction of Au(I)–thiolate complexes to evolution of Au25 nanoclusters. Journal of the American Chemical Society. 2014; 136 :10577-10580. DOI: 10.1021/ja505429f - 28.
Häkkinen H. The gold–sulfur interface at the nanoscale. Nature Chemistry. 2012; 4 :443-455. DOI: 10.1038/nchem.1352 - 29.
Zhu M, Aikens CM, Hollander FJ, Schatz GC, Jin R. Correlating the crystal structure of a thiol-protected Au25 cluster and optical properties. Journal of the American Chemical Society. 2008; 130 :5883-5885. DOI: 10.1021/ja801173r - 30.
Qian H, Eckenhoff WT, Zhu Y, Pintauer T, Jin R. Total structure determination of thiolate-protected Au38 nanoparticles. Journal of the American Chemical Society. 2010; 132 :8280-8281. DOI: 10.1021/ja103592z - 31.
Pei Y, Zeng XC. Investigating the structural evolution of thiolate protected gold clusters from first-principles. Nanoscale. 2012; 4 :4054-4072. DOI: 10.1039/c2nr30685a - 32.
Zhang P. X-ray spectroscopy of gold–thiolate nanoclusters. The Journal of Physical Chemistry C. 2014; 118 :25291-25299. DOI: 10.1021/jp507739u - 33.
Jiang DE, Kühn M, Tang Q, Weigend F. Superatomic orbitals under spin–orbit coupling. The Journal of Physical Chemistry Letters. 2014; 5 :3286-3289. DOI: 10.1021/jz501745z - 34.
Jadzinsky PD, Calero G, Ackerson CJ, Bushnell DA, Kornberg RD. Structure of a thiol monolayer-protected gold nanoparticle at 1.1 Å resolution. Science. 2007; 318 :430-433. DOI: 10.1126/science.1148624 - 35.
Knoppe S, Wong OA, Malola S, Häkkinen H, Bürgi T, Verbiest T, Ackerson CJ. Chiral phase transfer and enantioenrichment of thiolate-protected Au102 clusters. Journal of the American Chemical Society. 2014; 136 :4129-4132. DOI: 10.1021/ja500809p - 36.
Dolamic I, Knoppe S, Dass A, Bürgi T. First enantioseparation and circular dichroism spectra of Au38 clusters protected by achiral ligands. Nature Communications. 2012; 3 :798. DOI: 10.1038/ncomms1802 - 37.
Udayabhaskararao T, Pradeep T. New protocols for the synthesis of stable Ag and Au nanocluster molecules. The Journal of Physical Chemistry Letters. 2013; 4 :1553-1564. DOI: 10.1021/jz400332g - 38.
Dainese T, Antonello S, Gascón JA, Pan F, Perera NV, Ruzzi M, Venzo A, Zoleo A, Rissanen K, Maran F. Au25(SEt)18, a nearly naked thiolate-protected Au25 cluster: Structural analysis by single crystal X-ray crystallography and electron nuclear double resonance. ACS Nano. 2014; 8 :3904-3912. DOI: 10.1021/nn500805n - 39.
Li Y, Zaluzhna O, Tong YYJ. Critical role of water and the structure of inverse micelles in the Brust–Schiffrin synthesis of metal nanoparticles. Langmuir. 2011; 27 :7366-7370. DOI: 10.1021/la201158v - 40.
Kwak K, Kumar SS, Pyo K, Lee D. Ionic liquid of a gold nanocluster: A versatile matrix for electrochemical biosensors. ACS Nano. 2014; 8 :671-679. DOI: 10.1021/nn4053217 - 41.
Negishi Y, Kurashige W, Kamimura U. Isolation and structural characterization of an octaneselenolate-protected Au25 cluster. Langmuir. 2011; 27 :12289-12292. DOI: 10.1021/la203301p - 42.
Kurashige W, Yamaguchi M, Nobusada K, Negishi Y. Ligand-induced stability of gold nanoclusters: Thiolate versus selenolate. The Journal of Physical Chemistry Letters. 2012; 3 :2649-2652. DOI: 10.1021/jz301191t - 43.
Kurashige W, Yamazoe S, Kanehira K, Tsukuda T, Negishi Y. Selenolate-protected Au38 nanoclusters: Isolation and structural characterization. The Journal of Physical Chemistry Letters. 2013; 4 :3181-3185. DOI: 10.1021/jz401770y - 44.
Kurashige W, Munakata K, Nobusada K, Negishi Y. Synthesis of stable Cu n Au25-n nanoclusters (n = 1–9) using selenolate ligands. Chemical Communications. 2013;49 :5447-5449. DOI: 10.1039/c3cc41210e - 45.
Kurashige W, Yamazoe S, Yamaguchi M, Nishido K, Nobusada K, Tsukuda T, Negishi Y. Au25 clusters containing unoxidized tellurolates in the ligand shell. The Journal of Physical Chemistry Letters. 2014; 5 :2072-2076. DOI: 10.1021/jz500901f - 46.
Meng X, Xu Q, Wang S, Zhu M. Ligand-exchange synthesis of selenophenolate-capped Au25 nanoclusters. Nanoscale. 2012; 4 :4161-4165. DOI: 10.1039/c2nr30272a - 47.
Song Y, Wang S, Zhang J, Kang X, Chen S, Li P, Sheng H, Zhu M. Crystal structure of selenolate-protected Au24(SeR)20 nanocluster. Journal of the American Chemical Society. 2014; 136 :2963-2965. DOI: 10.1021/ja4131142 - 48.
Song Y, Zhong J, Yang S, Wang S, Cao T, Zhang J, Li P, Hu D, Pei Y, Zhu M. Crystal structure of Au25(SePh)18 nanoclusters and insights into their electronic, optical and catalytic properties. Nanoscale. 2014; 6 :13977-13985. DOI: 10.1039/c4nr04631e - 49.
Song Y, Abroshan H, Chai J, Kang X, Kim HJ, Zhu M, Jin R. Molecular-like transformation from PhSe-protected Au25 to Au23 nanocluster and its application. Chemistry of Materials. 2017; 29 :3055-3061. DOI: 10.1021/acs.chemmater.7b00058 - 50.
Song Y, Cao T, Deng H, Zhu X, Li P, Zhu M. Kinetically controlled, high-yield, direct synthesis of [Au25(SePh)18]−TOA+. Science China. 2014; 57 :1218-1224. DOI: 10.1007/s11426-014-5071-5 - 51.
Xu Q, Wang S, Liu Z, Xu G, Meng X, Zhu M. Synthesis of selenolate-protected Au18(SeC6H5)14 nanoclusters. Nanoscale. 2013; 5 :1176-1182. DOI: 10.1039/c2nr33466f - 52.
Maity P, Takano S, Yamazoe S, Wakabayashi T, Tsukuda T. Binding motif of terminal alkynes on gold clusters. Journal of the American Chemical Society. 2013; 135 :9450-9457. DOI: 10.1021/ja401798z - 53.
Wan XK, Tang Q, Yuan SF, Jiang DE, Wang QM. Au19 nanocluster featuring a V-shaped alkynyl−gold motif. Journal of the American Chemical Society. 2015; 137 :652-655. DOI: 10.1021/ja512133a - 54.
Lei Z, Wan XK, Yuan SF, Wang JQ, Wang QM. Alkynyl-protected gold and gold–silver nanoclusters. Dalton Transactions. 2017; 46 :3427-3434. DOI: 10.1039/c6dt04763g - 55.
Shichibu Y, Negishi Y, Watanabe T, Chaki NK, Kawaguchi H, Tsukuda T. Biicosahedral gold clusters [Au25(PPh3)10(SC n H2n +1)5Cl2]2+ (n = 2−18): A stepping stone to cluster-assembled materials. The Journal of Physical Chemistry C. 2007;111 :7845-7847. DOI: 10.1021/jp073101t - 56.
Koshevoy IO, Chang YC, Chen YA, Karttunen AJ, Grachova EV, Tunik SP, Jänis J, Pakkanen TA, Chou PT. Luminescent gold(I) alkynyl clusters stabilized by flexible diphosphine ligands. Organometallics. 2014; 33 :2363-2371. DOI: 10.1021/om5002952 - 57.
Song Y, Jin S, Kang X, Xiang J, Deng H, Yu H, Zhu M. How a single electron affects the properties of the “non-superatom” Au25 nanoclusters. Chemistry of Materials. 2016; 28 :2609-2617. DOI: 10.1021/acs.chemmater.5b04655 - 58.
Kobayashi N, Kamei Y, Shichibu Y, Konishi K. Protonation-induced chromism of pyridylethynyl-appended [core+exo]-type Au8 clusters. Resonance-coupled electronic perturbation through π-conjugated group. Journal of the American Chemical Society. 2013; 135 :16078-16081. DOI: 10.1021/ja4099092 - 59.
Kang X, Song Y, Deng H, Zhang J, Liu B, Pan C, Zhu M. Ligand-induced change of the crystal structure and enhanced stability of the Au11 nanocluster. RSC Advance. 2015; 5 :66879-66885. DOI: 10.1039/c5ra11674k - 60.
Song Y, Huang T, Murray RW. Heterophase ligand exchange and metal transfer between monolayer protected clusters. Journal of the American Chemical Society. 2003; 125 :11694-11701. DOI: 10.1021/ja0355731 - 61.
Lee D, Donkers RL, Wang G, Harper AS, Murray RW. Electrochemistry and optical absorbance and luminescence of molecule-like Au38 nanoparticles. Journal of the American Chemical Society. 2004; 126 :6193-6199. DOI: 10.1021/ja049605b - 62.
Guo R, Song Y, Wang G, Murray RW. Does core size matter in the kinetics of ligand exchanges of monolayer-protected Au clusters? Journal of the American Chemical Society. 2005; 127 :2752-2757. DOI: 10.1021/ja044638c - 63.
Hostetler MJ, Templeton AC, Murray RW. Dynamics of place-exchange reactions on monolayer-protected gold cluster molecules. Langmuir. 1999; 15 :3782-3789. DOI: 10.1021/la981598f - 64.
Tracy JB, Crowe MC, Parker JF, Hampe O, Fields-Zinna CA, Dass A, Murray RW. Electrospray ionization mass spectrometry of uniform and mixed monolayer nanoparticles: Au25[S(CH2)2Ph]18 and Au25[S(CH2)2Ph]18 -x (SR)x . Journal of the American Chemical Society. 2007;129 :16209-16215. DOI: 10.1021/ja076621a - 65.
Song Y, Murray RW. Dynamics and extent of ligand exchange depend on electronic charge of metal nanoparticles. Journal of the American Chemical Society. 2002; 124 :7096-7102. DOI: 10.1021/ja0174985 - 66.
Niihori Y, Hossain S, Kumar B, Nair LV, Kurashige W, Negishi Y. Perspective: Exchange reactions in thiolate-protected metal clusters. APL Materials. 2017; 5 :053201. DOI: 10.1063/1.4978373 - 67.
Niihori Y, Hossain S, Sharma S, Kumar B, Kurashige W, Negishi Y. Understanding and practical use of ligand and metal exchange reactions in thiolate-protected metal clusters to synthesize controlled metal clusters. The Chemical Record. 2017; 17 :473-484. DOI: 10.1002/tcr.201700002 - 68.
Wu Z, Suhan J, Jin R. One-pot synthesis of atomically monodisperse, thiol-functionalized Au25 nanoclusters. Journal of Materials Chemistry. 2009; 19 :622-626. DOI: 10.1039/b815983a - 69.
Schaaff TG, Whetten RL. Giant gold–glutathione cluster compounds: Intense optical activity in metal-based transitions. The Journal of Physical Chemistry B. 2000; 104 :2630-2641. DOI: 10.1021/jp993691y - 70.
Negishi Y, Takasugi Y, Sato S, Yao H, Kimura K, Tsukuda T. Magic-numbered Au n clusters protected by glutathione monolayers (n = 18, 21, 25, 28, 32, 39): Isolation and spectroscopic characterization. Journal of the American Chemical Society. 2004;126 :6518-6519. DOI: 10.1021/ja0483589 - 71.
Negishi Y, Nobusada K, Tsukuda T. Glutathione-protected gold clusters revisited: Bridging the gap between gold(I)−thiolate complexes and thiolate-protected gold nanocrystals. Journal of the American Chemical Society. 2005; 127 :5261-5270. DOI: 10.1021/ja042218h - 72.
Tsukuda T, Häkkinen H, editors. Protected Metal Clusters: From Fundamentals to Applications. 1st ed. Amsterdam: Elsevier; 2015. 372 p - 73.
Wolfe RL, Murray RW. Analytical evidence for the monolayer-protected cluster Au225[(S(CH2)5CH3)]75. Analytical Chemistry. 2006; 78 :1167-1173. DOI: 10.1021/ac051533z - 74.
Choi MMF, Douglas AD, Murray RW. Ion-pair chromatographic separation of water-soluble gold monolayer-protected clusters. Analytical Chemistry. 2006; 78 :2779-2785. DOI: 10.1021/ac052167m - 75.
Negishi Y, Nakazaki T, Malola S, Takano S, Niihori Y, Kurashige W, Yamazoe S, Tsukuda T, Häkkinen H. A critical size for emergence of nonbulk electronic and geometric structures in dodecanethiolate-protected Au clusters. Journal of the American Chemical Society. 2015; 137 :1206-1212. DOI: 10.1021/ja5109968 - 76.
Niihori Y, Matsuzaki M, Uchida C, Negishi Y. Advanced use of high-performance liquid chromatography for synthesis of controlled metal clusters. Nanoscale. 2014; 6 :7889-7896. DOI: 10.1039/c4nr01144a - 77.
Black DM, Bhattarai N, Bach SBH, Whetten RL. Selection and identification of molecular gold clusters at the nano(gram) scale: Reversed phase HPLC–ESI–MS of a mixture of Au-peth MPCs. The Journal of Physical Chemistry Letters. 2016; 7 :3199-3205. DOI: 10.1021/acs.jpclett.6b01403 - 78.
Negishi Y, Chaki NK, Shichibu Y, Whetten RL, Tsukuda T. Origin of magic stability of thiolated gold clusters: A case study on Au25(SC6H13)18. Journal of the American Chemical Society. 2007; 129 :11322-11323. DOI: 10.1021/ja073580+ - 79.
Chaki NK, Negishi Y, Tsunoyama H, Shichibu Y, Tsukuda T. Ubiquitous 8 and 29 kDa gold: Alkanethiolate cluster compounds: Mass-spectrometric determination of molecular formulas and structural implications. Journal of the American Chemical Society. 2008; 130 :8608-8610. DOI: 10.1021/ja8005379 - 80.
Schaaff TG, Whetten RL. Controlled etching of Au:SR cluster compounds. The Journal of Physical Chemistry B. 1999; 103 :9394-9396. DOI: 10.1021/jp993229d - 81.
Shichibu Y, Negishi Y, Tsunoyama H, Kanehara M, Teranishi T, Tsukuda T. Extremely high stability of glutathionate-protected Au25 clusters against core etching. Small. 2007; 3 :835-839. DOI: 10.1002/smll.200600611 - 82.
Jin R, Qian H, Wu Z, Zhu Y, Zhu M, Mohanty A, Garg N. Size focusing: A methodology for synthesizing atomically precise gold nanoclusters. The Journal of Physical Chemistry Letters. 2010; 1 :2903-2910. DOI: 10.1021/jz100944k - 83.
Zeng C, Chen Y, Das A, Jin R. Transformation chemistry of gold nanoclusters: From one stable size to another. The Journal of Physical Chemistry Letters. 2015; 6 :2976-2986. DOI: 10.1021/acs.jpclett.5b01150 - 84.
Häkkinen H, Barnett RN, Landman U. Electronic structure of passivated Au38(SCH3)24 nanocrystal. Physical Review Letters. 1999; 82 :3264-3267. DOI: 10.1103/PhysRevLett.82.3264 - 85.
Zeng C, Qian H, Li T, Li G, Rosi NL, Yoon B, Barnett RN, Whetten RL, Landman U, Jin R. Total structure and electronic properties of the gold nanocrystal Au36(SR)24. Angewandte Chemie International Edition. 2012; 51 :13114-13118. DOI: 10.1002/anie.201207098 - 86.
Dass A, Theivendran S, Nimmala PR, Kumara C, Jupally VR, Fortunelli A, Sementa L, Barcaro G, Zuo X, Noll BC. Au133(SPh- t Bu)52 nanomolecules: X-ray crystallography, optical, electrochemical, and theoretical analysis. Journal of the American Chemical Society. 2015;137:4610-4613. DOI: 10.1021/ja513152h - 87.
Das A, Li T, Nobusada K, Zeng C, Rosi NL, Jin R. Nonsuperatomic [Au23(SC6H11)16]− nanocluster featuring bipyramidal Au15 kernel and trimeric Au3(SR)4 motif. Journal of the American Chemical Society. 2013; 135 :18264-18267. DOI: 10.1021/ja409177s - 88.
Heaven MW, Dass A, White PS, Holt KM, Murray RW. Crystal structure of the gold nanoparticle [N(C8H17)4][Au25(SCH2CH2Ph)18]. Journal of the American Chemical Society. 2008; 130 :3754-3755. DOI: 10.1021/ja800561b - 89.
Pohjolainen E, Häkkinen H, Clayborne A. The role of the anchor atom in the ligand of the monolayer-protected Au25(XR)18− nanocluster. The Journal of Physical Chemistry C. 2015; 119 :9587-9594. DOI: 10.1021/acs.jpcc.5b01068 - 90.
Kumar S, Jin R. Water-soluble Au25(Capt)18 nanoclusters: Synthesis, thermal stability, and optical properties. Nanoscale. 2012; 4 :4222-4227. DOI: 10.1039/C2NR30833A - 91.
Lin SY, Chen NT, Sum SP, Lo LW, Yang CS. Ligand exchanged photoluminescent gold quantum dots functionalized with leading peptides for nuclear targeting and intracellular imaging. Chemical Communications. 2008:4762-4764. DOI: 10.1039/b808207c - 92.
Kano S, Azuma Y, Kanehara M, Teranishi T, Majima Y. Room-temperature coulomb blockade from chemically synthesized Au nanoparticles stabilized by acid–base interaction. Applied Physics Express. 2010; 3 :105003. DOI: 10.1143/APEX.3.105003 - 93.
Lopez-Acevedo O, Tsunoyama H, Tsukuda T, Häkkinen H, Aikens CM. Chirality and electronic structure of the thiolate-protected Au38 nanocluster. Journal of the American Chemical Society. 2010; 132 :8210-8218. DOI: 10.1021/ja102934q - 94.
Malola S, Lehtovaara L, Knoppe S, Hu KJ, Palmer RE, Bürgi T, Häkkinen H. Au40(SR)24 cluster as a chiral dimer of 8-electron superatoms: Structure and optical properties. Journal of the American Chemical Society. 2012; 134 :19560-19563. DOI: 10.1021/ja309619n - 95.
Knoppe S, Bürgi T. Chirality in thiolate-protected gold clusters. Accounts of Chemical Research. 2014; 47 :1318-1326. DOI: 10.1021/ar400295d - 96.
Noyori R. Asymmetric catalysis: Science and opportunities (nobel lecture). Angewandte Chemie International Edition. 2002; 41 :2008-2022. DOI: 10.1002/1521-3773(20020617)41:12<2008::AID-ANIE2008>3.0.CO;2-4 - 97.
de la Llave E, Scherlis DA. Selenium-based self-assembled monolayers: The nature of adsorbate−surface interactions. Langmuir. 2010; 26 :173-178. DOI: 10.1021/la903660y - 98.
Szelagowska-Kunstman K, Cyganik P, Schüpbach B, Terfort A. Relative stability of thiol and selenol based SAMs on Au(111)−exchange experiments. Physical Chemistry Chemical Physics. 2010; 12 :4400-4406. DOI: 10.1039/b923274p - 99.
Kurashige W, Niihori Y, Sharma S, Negishi Y. Precise synthesis, functionalization and application of thiolate-protected gold clusters. Coordination Chemistry Reviews. 2016; 320-321 :238-250. DOI: 10.1016/j.ccr.2016.02.013 - 100.
Romashov LV, Ananikov VP. Self-assembled selenium monolayers: From nanotechnology to materials science and adaptive catalysis. Chemistry—A European Journal. 2013; 19 :17640-17660. DOI: 10.1002/chem.201302115 - 101.
Yokota K, Taniguchi M, Kawai T. Control of the electrode−molecule interface for molecular devices. Journal of the American Chemical Society. 2007; 129 :5818-5819. DOI: 10.1021/ja071365n - 102.
Jin R, Zeng C, Zhou M, Chen Y. Atomically precise colloidal metal nanoclusters and nanoparticles: Fundamentals and opportunities. Chemical Reviews. 2016; 116 :10346-10413. DOI: 10.1021/acs.chemrev.5b00703 - 103.
Ni TW, Tofanelli MA, Phillips BD, Ackerson CJ. Structural basis for ligand exchange on Au25(SR)18. Inorganic Chemistry. 2014; 53 :6500-6502. DOI: 10.1021/ic5010819 - 104.
Niihori Y, Kikuchi Y, Kato A, Matsuzaki M, Negishi Y. Understanding ligand-exchange reactions on thiolate-protected gold clusters by probing isomer distributions using reversed-phase high-performance liquid chromatography. ACS Nano. 2015; 9 :9347-9356. DOI: 10.1021/acsnano.5b03435 - 105.
Fernando A, Aikens CM. Ligand exchange mechanism on thiolate monolayer protected Au25(SR)18 nanoclusters. The Journal of Physical Chemistry C. 2015; 119 :20179-20187. DOI: 10.1021/acs.jpcc.5b06833 - 106.
Hossain S, Kurashige W, Wakayama S, Kumar B, Nair LV, Niihori Y, Negishi Y. Ligand exchange reactions in thiolate-protected Au25 nanoclusters with selenolates or tellurolates: Preferential exchange sites and effects on electronic structure. The Journal of Physical Chemistry C. 2016; 120 :25861-25869. DOI: 10.1021/acs.jpcc.6b08636 - 107.
Zhu M, Qian H, Jin R. Thiolate-protected Au24(SC2H4Ph)20 nanoclusters: Superatoms or not? The Journal of Physical Chemistry Letters. 2010; 1 :1003-1007. DOI: 10.1021/jz100133n - 108.
Pei Y, Pal R, Liu C, Gao Y, Zhang Z, Zeng XC. Interlocked catenane-like structure predicted in Au24(SR)20: Implication to structural evolution of thiolated gold clusters from homoleptic gold(I) thiolates to core-stacked nanoparticles. Journal of the American Chemical Society. 2012; 134 :3015-3024. DOI: 10.1021/ja208559y - 109.
Das A, Li T, Li G, Nobusada K, Zeng C, Rosi NL, Jin R. Crystal structure and electronic properties of a thiolate-protected Au24 nanocluster. Nanoscale. 2014; 6 :6458-6462. DOI: 10.1039/c4nr01350f - 110.
Tang Q, Ouyang R, Tian Z, Jiang DE. The ligand effect on the isomer stability of Au24(SR)20 clusters. Nanoscale. 2015; 7 :2225-2229. DOI: 10.1039/c4nr05826g - 111.
Chen Y, Liu C, Tang Q, Zeng C, Higaki T, Das A, Jiang DE, Rosi NL, Jin R. Isomerism in Au28(SR)20 nanocluster and stable structures. Journal of the American Chemical Society. 2016; 138 :1482-1485. DOI: 10.1021/jacs.5b12094 - 112.
Zeng C, Liu C, Pei Y, Jin R. Thiol ligand-induced transformation of Au38(SC2H4Ph)24 to Au36(SPh- t -Bu)24. ACS Nano. 2013;7 :6138-6145. DOI: 10.1021/nn401971g