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Chen S, Higaki T, Ma H, Zhu M, Jin R, Wang G. Inhomogeneous Quantized Single-Electron Charging and Electrochemical-Optical Insights on Transition-Sized Atomically Precise Gold Nanoclusters. ACS NANO 2020; 14:16781-16790. [PMID: 33196176 DOI: 10.1021/acsnano.0c04914] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Small differences in electronic structures, such as an emerging energy band gaps or the splitting of degenerated orbitals, are very challenging to resolve but important for nanomaterials properties. A signature electrochemical property called quantized double layer charging, i.e., "continuous" one-electron transfers (1e, ETs), in atomically precise Au133(TBBT)52, Au144(BM)60, and Au279(TBBT)84 is analyzed to reveal the nonmetallic to metallic transitions (whereas TBBT is 4-tert-butylbenzenethiol and BM is benzyl mercaptan; abbreviated as Au133, Au144, and Au279). Subhundred milli-eV energy differences are resolved among the "often-approximated uniform" peak spacings from multipairs of reversible redox peaks in voltammetric analysis, with single ETs as internal standards for calibration and under temperature variations. Cyclic and differential pulse voltammetry experiments reveal a 0.15 eV energy gap for Au133 and a 0.17 eV gap for Au144 at 298 K. Au279 is confirmed metallic, displaying a "bulk-continuum" charging response without an energy gap. The energy gaps and double layer capacitances of Au133 and Au144 increase as the temperature decreases. The temperature dependences of charging energies and HOMO-LUMO gaps of Au133 and Au144 are attributed to the counterion permeation and the steric hindrance of ligand, as well as their molecular compositions. With the subtle energy differences resolved, spectroelectrochemistry features of Au133 and Au144 are compared with ultrafast spectroscopy to demonstrate a generalizable analysis approach to correlate steady-state and transient energy diagram for the energy-in processes. Electrochemiluminescence (ECL), one of the energy-out processes after the charge transfer reactions, is reported for the three samples. The ECL intensity of Au279 is negligible, whereas the ECLs of Au133 and Au144 are relatively stronger and observable (but orders of magnitudes weaker than our recently reported bimetallic Au12Ag13). Results from these atomically precise nanoclusters also demonstrate that the combined voltammetric and spectroscopic analyses, together with temperature variations, are powerful tools to reveal subtle differences and gain insights otherwise inaccessible in other nanomaterials.
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Affiliation(s)
- Shuang Chen
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, People's Republic of China
- Key Laboratory of Structure and Functional Regulation of Hybrid Materials, Ministry of Education, Anhui University, Hefei, 230601, People's Republic of China
| | - Tatsuya Higaki
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Hedi Ma
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30302, United States
| | - Manzhou Zhu
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, People's Republic of China
- Key Laboratory of Structure and Functional Regulation of Hybrid Materials, Ministry of Education, Anhui University, Hefei, 230601, People's Republic of China
| | - Rongchao Jin
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Gangli Wang
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30302, United States
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Wang J, Chen J, Wei Q, Cheng SB. On the dual aromaticity and external field induced superhalogen modulation of the AuSc2 cluster: A computational study. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2020.137767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Li J, Huang HC, Wang J, Zhao Y, Chen J, Bu YX, Cheng SB. Polymeric tungsten carbide nanoclusters: structural evolution, ligand modulation, and assembled nanomaterials. NANOSCALE 2019; 11:19903-19911. [PMID: 31599909 DOI: 10.1039/c9nr05613k] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Seeking novel superatoms with tunable electronic and magnetic properties has attracted much interest due to their potential application in cluster assembly nanomaterials. By employing density functional theory (DFT) calculations, the recently observed superatomic WC cluster was adopted as the basic unit to construct larger polymeric clusters, namely (WC)n (n = 2-7), and their structural evolution was explored to understand the growth pattern of these superatomic clusters into nanoscale materials. An unusual odd-even pattern in structural evolution was disclosed, in which the (WC)2 unit is considered as the basic building block. Moreover, W4C4 is found to possess a cubic structure, based on which the CO and PH3 ligands were attached to examine their ligation effects on W4C4. Theoretical results show that the electronic properties of W4C4 can be dramatically altered during the ligation process. Intriguingly, the continuous attachment of CO and PH3 ligands strongly increases and decreases the electron affinities (EA) and ionization potentials (IP) of the ligated W4C4 clusters, respectively, leading to the formation of superhalogen and superalkali species with high magnetic moments. The observed ligand induced strategy highlighted here could serve as an effective way to tune the electronic and magnetic properties of clusters resulting in the formation of novel superatoms. Finally, studies on the geometrical and electronic structures of the W4C4 cluster solid unveil its special 3-D cubic honeycomb geometry and metallic properties with predominant contribution from the 5d of W, which may have potential applications in electro-catalysis.
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Affiliation(s)
- Jun Li
- Key Laboratory for Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
| | - Hai-Cai Huang
- Key Laboratory for Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
| | - Jing Wang
- Key Laboratory for Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
| | - Yang Zhao
- Key Laboratory for Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
| | - Jing Chen
- Key Laboratory for Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China. and Suzhou Institute of Shandong University, Suzhou, Jiangsu 215123, People's Republic of China
| | - Yu-Xiang Bu
- Key Laboratory for Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China. and School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, People's Republic of China
| | - Shi-Bo Cheng
- Key Laboratory for Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
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Whetten RL, Weissker HC, Pelayo JJ, Mullins SM, López-Lozano X, Garzón IL. Chiral-Icosahedral ( I) Symmetry in Ubiquitous Metallic Cluster Compounds (145A,60X): Structure and Bonding Principles. Acc Chem Res 2019; 52:34-43. [PMID: 30600992 DOI: 10.1021/acs.accounts.8b00481] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
There exists a special kind of perfection-in symmetry, simplicity, and stability-attainable for structures generated from precisely 60 ligands (all of a single type) that protect 145 metal-atom sites. The symmetry in question is icosahedral ( Ih), generally, and chiral icosahedral ( I) in particular. A 60-fold equivalence of the ligands is the smallest number to allow this kind of perfection. Known cluster compounds that approximate this structural ideal include palladium-carbonyls, Ih-Pd145(CO)60; gold-thiolates, I-Au144(SR)60; and gold-alkynyls, I-Au144(C2R)60. Many other variants are suspected. The Pd145 compound established the basic achiral structure-type. However, the Au144-thiolate archetype is prominent, historically in its abundance and ease of preparation and handling, in its proliferation in many laboratories and application areas, and ultimately in the intrinsic chirality of its geometrical structure and organization of its bonding network or connectivity. As discovered by mass spectrometry (the "30-k anomaly") in 1995, it appeared as a broad single peak, as solitary and symmetrical as Mount Fuji, centered near 30 kDa (∼150 Au atoms), provoking these thoughts: Surely this phenomenon requires a unique explanation. It appears to be the Buckminsterfullerene (carbon-60) of gold-cluster chemistry. Herein we provide an elementary account of the unexpected discovery, in which the Pd145-structure played a critical role, that led to the identification and prediction, in 2008, of a fascinating new molecular structure-type, evidently the first one of chiral icosahedral symmetry. Rigorous confirmation of this prediction occurred in early spring 2018, when two single-crystal X-ray crystallography reports were submitted, each one distinguishing both enantiomeric structures and noting profound chirality for the surface (ligand) layer. The emphasis here is on the structure and bonding principles and how these have been elucidated. Our aim has been to present this story in simplest terms, consistent with the radical simplicity of the structure itself. Because it combines intrinsic profound chirality, at several levels, with the highest possible symmetry-type (icosahedral), the structure may attract broader interest also from educators, especially if studied in tandem with the analysis of hollow (shell) metallic systems that exhibit the same chirality and symmetry. Because the shortest (stiffest) bonds follow the chiral 3-way weave pattern of the traditional South-Asian reed football, this cultural artifact may be used to introduce chiral-icosahedral symmetry in a pleasant and memorable way. One may also appreciate easily the bonding and excitations in I-symmetry metallic nanostructures via the golden fullerenes, that is, the proposed hollow Au60,72 spheres. Beyond any aesthetic or pedagogical value, we aim that our Account may provide a firm foundation upon which others may address open questions and the opportunities they present. This Account can scarcely hint at the prospects for further fundamental understanding of these compounds, as well as a widening sphere of applications (chemical, electronic, imaging). The compounds remain crucial to a wider field presently under intense development.
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Affiliation(s)
- Robert L. Whetten
- Department of Physics & Astronomy, University of Texas, San Antonio, Texas 78249, United States
| | - Hans-Christian Weissker
- Aix Marseille University and European Theoretical Spectroscopy Facility, CNRS, CINaM UMR 7325, 13288 Marseille, France
- European Theoretical Spectroscopy Facility
| | - J. Jesús Pelayo
- Escuela Superior de Apan, Universidad Autónoma del Estado de Hidalgo, Chimalpa Tlalayote, Apan, 43920 Hidalgo, México
| | - Sean M. Mullins
- Department of Physics & Astronomy, University of Texas, San Antonio, Texas 78249, United States
| | - Xochitl López-Lozano
- Department of Physics & Astronomy, University of Texas, San Antonio, Texas 78249, United States
| | - Ignacio L. Garzón
- Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal
20-364, 01000 CDMX, México
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Sinha-Roy R, García-González P, López Lozano X, Whetten RL, Weissker HC. Identifying Electronic Modes by Fourier Transform from δ-Kick Time-Evolution TDDFT Calculations. J Chem Theory Comput 2018; 14:6417-6426. [PMID: 30404453 DOI: 10.1021/acs.jctc.8b00750] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Time-dependent density-functional theory (TDDFT) is widely used for calculating electron excitations in clusters and large molecules. For optical excitations, TDDFT is customarily applied in two distinct approaches: transition-based linear-response TDDFT (LR-TDDFT) and the real-time formalism (RT-TDDFT). The former directly provides the energies and transition densities of the excitations, but it requires the calculation of a large number of empty electron states, which makes it cumbersome for large systems. By contrast, RT-TDDFT circumvents the evaluation of empty orbitals, which is especially advantageous when dealing with large systems. A drawback of the procedure is that information about the nature of individual spectral features is not automatically obtained, although it is of course contained in the time-dependent induced density. Fourier transform of the induced density has been used in some simple cases, but the method is, surprisingly, not widely used to complement the RT-TDDFT calculations; although the reliability of RT-TDDFT spectra is now widely accepted, a critical assessment for the corresponding transition densities and a demonstration of the technical feasibility of the Fourier-transform evaluation for general cases is still lacking. In the present work, we show that the transition densities of the optically allowed excitations can be efficiently extracted from a single δ-kick time-evolution calculation even in complex systems like noble metals. We assess the results by comparison with the corresponding LR-TDDFT ones and also with the induced densities arising from RT-TDDFT simulations of the excitation process.
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Affiliation(s)
- Rajarshi Sinha-Roy
- Aix-Marseille University , CNRS, CINaM , 13288 Marseille , France.,Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC) , Universidad Autónoma de Madrid , E-28049 Madrid , Spain.,European Theoretical Spectroscopy Facility (ETSF)
| | - Pablo García-González
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC) , Universidad Autónoma de Madrid , E-28049 Madrid , Spain.,European Theoretical Spectroscopy Facility (ETSF)
| | - Xóchitl López Lozano
- Department of Physics & Astronomy , The University of Texas at San Antonio , One UTSA Circle , San Antonio , Texas 78249-0697 , United States
| | - Robert L Whetten
- Department of Physics & Astronomy , The University of Texas at San Antonio , One UTSA Circle , San Antonio , Texas 78249-0697 , United States
| | - Hans-Christian Weissker
- Aix-Marseille University , CNRS, CINaM , 13288 Marseille , France.,European Theoretical Spectroscopy Facility (ETSF)
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Shen XT, Ma XL, Ni QL, Ma MX, Gui LC, Hou C, Hou RB, Wang XJ. [Ag 15(N-triphos) 4(Cl 4)](NO 3) 3: a stable Ag-P superatom with eight electrons (N-triphos = tris((diphenylphosphino)methyl)amine). NANOSCALE 2018; 10:515-519. [PMID: 29239443 DOI: 10.1039/c7nr07308a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A first and stable Ag-P superatom nanocluster [Ag15(N-triphos)4(Cl4)](NO3)3 (1) has been successfully synthesized and characterized. X-ray analysis shows that this Ag15 cluster has a hexacapped body-centered cubic (bcc) framework which is consolidated by four tripodal N-triphos ligands. The identity of 1 is confirmed by high resolution ESI-MS. Cluster 1 has an electronic and geometric shell closure structure with 8 free electrons, matching the stability idea of superatom theory for a nanocluster. DFT calculation of this Ag15 cluster reveals the superatom feature with a 1S21P6 configuration. The chelation of multidentate phosphines enhances the stability of this Ag15 cluster. The AgAg distances between the centered and the vertical Ag atoms of this bcc (Ag@Ag8) are in the range of 2.57-2.71 Å, and the distances between the face-capped and the vertical silver atoms are in the range of 2.84-2.92 Å, showing strong AgAg interactions within this cluster core. This superatom complex exhibits a relatively high thermal and photolytic stability.
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Affiliation(s)
- Xue-Tao Shen
- School of Chemistry and Pharmaceutical Sciences, Guangxi Key Laboratory of Low Carbon Energy Materials, Guangxi Normal University, Yu Cai Road 15, Qi Xin District, Guilin 541004, Guangxi, China.
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