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An effective strategy is developed to synthesize high‐nuclearity Cu clusters, [Cu53(RCOO)10(C≡CtBu)20Cl2H18]+ (Cu53), which is the largest CuI/Cu0 cluster reported to date. Cu powder and Ph2SiH2 are employed as the reducing agents in the synthesis. As revealed by single‐crystal diffraction, Cu53 is arranged as a four‐concentric‐shell Cu3@Cu10Cl2@Cu20@Cu20 structure, possessing an atomic arrangement of concentric M12 icosahedral and M20 dodecahedral shells which popularly occurs in Au/Ag nanoclusters. Surprisingly, Cu53 can be dissolved in diethyl ether and spin coated to form uniform nanoclusters film on organolead halide perovskite. The cluster film can subsequently be converted into high‐quality CuI film via in situ iodination at room temperature. The as‐fabricated CuI film is an excellent hole‐transport layer for fabricating highly stable CuI‐based perovskite solar cells (PSCs) with 14.3 % of efficiency. An effective strategy is developed to synthesize high‐nuclearity Cu53 clusters that are surface‐capped by alkynyl and acetate ligands. These nanoclusters are unexpectedly soluble in ether, enabling the easy formation of high‐quality films. The cluster films are readily converted into high‐quality CuI thin films for applications as a hole transport layer in perovskite solar cells. [ABSTRACT FROM AUTHOR]

Abstract: A general method, using mixed ligands (here diphosphines and thiolates) is devised to turn an achiral metal cluster, Au13Cu2, into an enantiomeric pair by breaking (lowering) the overall molecular symmetry with the ligands. Using an achiral diphosphine, a racemic [Au13Cu2(DPPP)3(SPy)6]+ was prepared which crystallizes in centrosymmetric space groups. Using chiral diphosphines, enantioselective synthesis of an optically pure, enantiomeric pair of [Au13Cu2((2r,4r)/(2s,4s)‐BDPP)3(SPy)6]+ was achieved in one pot. Their circular dichroism (CD) spectra give perfect mirror images in the range of 250–500 nm with maximum anisotropy factors of 1.2×10−3. DFT calculations provided good correlations with the observed CD spectra of the enantiomers and, more importantly, revealed the origin of the chirality. Racemization studies show high stability (no racemization at 70 °C) of these chiral nanoclusters, which hold great promise in applications such as asymmetry catalysis. [ABSTRACT FROM AUTHOR]

We report herein the synthesis and structure of a 45-atom trigonal-prismatic Au–Ag bimetallic nanocluster, formulated as Au9Ag36(SPhCl2)27(PPh3)6, based on single-crystal X-ray crystallographic determination. The structure can be described as a core–shell structure with a tricapped trigonal prismatic (ttp1) Au9 core encaged in a larger (frequency-two) tricapped trigonal prismatic (ttp2) Ag30 shell. The cluster is terminated by six Ag(PPh3) moieties which, along with ttp2 and 27 thiolates, constitute the outer trigonal-prismatic (TP) shell. Each of the three nearly coplanar yet severely distorted “square” faces of TP contains 13 Ag atoms which are arranged in a way reminiscent of the (100) face of a face-centered cubic (fcc) structure. Of the 30 edges formed by these quasi-(100) faces of the TP, only 27 are bridged by the thiolate ligands; three are vacant, one on each “square” face. It is believed that these peculiar vacant ligand sites are caused by steric hindrance of the thiolate ligands in combination with the superatomic electronic shell closing of 1S21P61D10 rendering 9(ttp1) + 30(ttp2) + 6(TP) − 27(SR) = 18 jellium electrons. [ABSTRACT FROM AUTHOR]

An effective strategy is developed to synthesize high-nuclearity Cu clusters, [Cu 53 (RCOO) 10 (C≡CtBu) 20 Cl 2 H 18 ] + (Cu 53 ), which is the largest Cu I /Cu 0 cluster reported to date. Cu powder and Ph 2 SiH 2 are employed as the reducing agents in the synthesis. As revealed by single-crystal diffraction, Cu 53 is arranged as a four-concentric-shell Cu 3 @Cu 10 Cl 2 @Cu 20 @Cu 20 structure, possessing an atomic arrangement of concentric M 12 icosahedral and M 20 dodecahedral shells which popularly occurs in Au/Ag nanoclusters. Surprisingly, Cu 53 can be dissolved in diethyl ether and spin coated to form uniform nanoclusters film on organolead halide perovskite. The cluster film can subsequently be converted into high-quality CuI film via in situ iodination at room temperature. The as-fabricated CuI film is an excellent hole-transport layer for fabricating highly stable CuI-based perovskite solar cells (PSCs) with 14.3 % of efficiency., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A general method, using mixed ligands (here diphosphines and thiolates) is devised to turn an achiral metal cluster, Au 13 Cu 2 , into an enantiomeric pair by breaking (lowering) the overall molecular symmetry with the ligands. Using an achiral diphosphine, a racemic [Au 13 Cu 2 (DPPP) 3 (SPy) 6 ] + was prepared which crystallizes in centrosymmetric space groups. Using chiral diphosphines, enantioselective synthesis of an optically pure, enantiomeric pair of [Au 13 Cu 2 ((2r,4r)/(2s,4s)-BDPP) 3 (SPy) 6 ] + was achieved in one pot. Their circular dichroism (CD) spectra give perfect mirror images in the range of 250-500 nm with maximum anisotropy factors of 1.2×10 -3 . DFT calculations provided good correlations with the observed CD spectra of the enantiomers and, more importantly, revealed the origin of the chirality. Racemization studies show high stability (no racemization at 70 °C) of these chiral nanoclusters, which hold great promise in applications such as asymmetry catalysis., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

By using ethylene glycol and monocarboxylic acid as surface ligands, a series of cyclic Ti-oxo clusters (CTOC) with permanent microporosity are successfully synthesized. With a cyclic {Ti 32 O 16 } backbone made of eight connected Ti 4 tetrahedral cages that are arranged in a zigzag fashion, the clusters have a "donut" shape with an inner diameter of 8.3 Å, outer diameter of 26.9 Å and height of 10.4 Å. While both inner and outer walls of the "donut" clusters are modified by double-deprotonated ethylene glycolates, their upper and lower surfaces are bound by carboxylates and mono-deprotonated ethylene glycolates. The clusters are readily packed into one-dimensional tubes which are further arranged in two different modes into crystalline microporous solids with surface areas over 660 m 2  g -1 , depending on the surface carboxylates. The solid with olefin-bearing carboxylates exhibits a superior CO 2 adsorption capacity of 40 cm 3  g -1 at 273 K under 1 atm. Moreover, the mono-deprotonated ethylene glycolates on the clusters are demonstrated to be highly exchangeable by other alcohols, providing a nice platform for creating microporous solids or films with a wide variety of surface functionalities., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Understanding the nucleation and growth pathways of nanocrystallites allows precise control of the size and shape of functional crystalline nanomaterials of importance in nanoscience and nanotechnology. This paper provides a detailed analysis of the stereochemical and electronic requirements of three series of nanoclusters based on face-centered cubes (fcc) as the basic building blocks, namely, 1-, 2-, and 3-D assemblages of fcc to form superrods (n), supersquares (n 2 ), and supercubes (n 3 ). The generating functions for calculating the numbers (and arrangements) of surface and interior metal atoms, as well as the number and dispositions of the ligands, for these particular sequences of fcc metal clusters of the general formula [M m (SR) l (PR' 3 ) 8 ] q (where M = coinage metals; SR = thiolates (or group XI ligands), and PR' 3 = phosphines) are presented. An electron-counting scheme based on the jelliumatic shell nodel, a variant of the jellium model, predicts the electron requirements and hence the chemical compositions that are critical in the design and synthesis of the next generation of giant nanoclusters in the nanorealm. The ligand binding specificities, which are keys to effective surface ligand control of the size and shape of these nanoclusters, are defined. Finally, a connection is made with regard to the growth of fcc metals, n 3 , from fcc supercubes (n < 10) to fcc nanocrystallites/particles (10 < n < 10 2 ) and to fcc bulk phase (n > 10 2 ).

We report herein the synthesis and structure of a 45-atom trigonal-prismatic Au-Ag bimetallic nanocluster, formulated as Au 9 Ag 36 (SPhCl 2 ) 27 (PPh 3 ) 6 , based on single-crystal X-ray crystallographic determination. The structure can be described as a core-shell structure with a tricapped trigonal prismatic (ttp1) Au 9 core encaged in a larger (frequency-two) tricapped trigonal prismatic (ttp2) Ag 30 shell. The cluster is terminated by six Ag(PPh 3 ) moieties which, along with ttp2 and 27 thiolates, constitute the outer trigonal-prismatic (TP) shell. Each of the three nearly coplanar yet severely distorted "square" faces of TP contains 13 Ag atoms which are arranged in a way reminiscent of the (100) face of a face-centered cubic (fcc) structure. Of the 30 edges formed by these quasi-(100) faces of the TP, only 27 are bridged by the thiolate ligands; three are vacant, one on each "square" face. It is believed that these peculiar vacant ligand sites are caused by steric hindrance of the thiolate ligands in combination with the superatomic electronic shell closing of 1S 2 1P 6 1D 10 rendering 9(ttp1) + 30(ttp2) + 6(TP) - 27(SR) = 18 jellium electrons.

Demonstrated herein are the preparation and crystallographic characterization of the family of fcc silver nanoclusters from Nichol's cube to Rubik's cube and beyond via ligand-control (thiolates and phosphines in this case). The basic building block is our previously reported fcc cluster [Ag 14 (SPhF 2 ) 12 (PPh 3 ) 8 ] (1). The metal frameworks of [Ag 38 (SPhF 2 ) 26 (PR' 3 ) 8 ] (2 2 ) and [Ag 63 (SPhF 2 ) 36 (PR' 3 ) 8 ] + (2 3 ), where HSPhF 2 = 3,4-difluorothiophenol and R' = alkyl/aryl, are composed of 2 × 2 = 4 and 2 × 2 × 2 = 8 metal cubes of 1, respectively. All serial clusters share similar surface structural features. The thiolate ligands cap the six faces and the 12 edges of the cube (or half cube) while the phosphine ligands are terminally bonded to its eight corners. On the basis of the analysis of the crystal structures of 1, 2 2 , and 2 3 , we predict the next "cube of cubes" to be Ag 172 (SR) 72 (PR' 3 ) 8 ] (3 3 ), in the evolution of growth of this cluster sequence.

In this work, a facile ion-pairing strategy for asymmetric synthesis of optically active negatively charged chiral metal nanoparticles using chiral ammonium cations is demonstrated. A new thiolated chiral three-concentric-shell cluster, [Ag 28 Cu 12 (SR) 24 ] 4- , was first synthesized as a racemic mixture and characterized by single-crystal X-ray structure determination. Mass spectrometric measurements revealed relatively strong ion-pairing interactions between the anionic nanocluster and ammonium cations. Inspired by this observation, the as-prepared racemic mixture was separated into enantiomers by employing chiral quaternary ammonium salts as chiral resolution agents. Subsequently, direct asymmetric synthesis of optically active enantiomers of [Ag 28 Cu 12 (SR) 24 ] 4- was achieved by using appropriate chiral ammonium cations (such as N-benzylcinchoninium vs N-benzylcinchonidinium) in the cluster synthesis. These simple strategies, ion-pairing enantioseparation and direct asymmetric synthesis using chiral counterions, may be of general use in preparing chiral metal nanoparticles.

A green gold-cluster, Au30S(StBu)18, was successfully prepared in high yield and crystallographically characterized. Each cluster consists of an Au22 core capped by a mixed layer of staple Au-thiolate units, bridging thiolates and a μ3-S(2-).