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Landi A, Summa FF, Zanasi R, Monaco G. On the JAP Method for the Indirect Determination of Delocalized Currents from Experimental Chemical Shifts. Chemphyschem 2022; 23:e202200411. [PMID: 35811448 PMCID: PMC9796333 DOI: 10.1002/cphc.202200411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/02/2022] [Indexed: 01/01/2023]
Abstract
The JAP model (after Jirásek, Anderson, and Peeks) to retrieve global current strengths from experimental 1 H chemical shifts has been tested with DFT computations. Both global and local tropicities are correctly predicted in most cases and the quantitative agreement is overall fair. An extension of the model is found to give improvement in an exemplary critical case, where the global delocalized current is negligible and the current density map is dominated by local currents.
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Affiliation(s)
- Alessandro Landi
- Department of Chemistry and Biology “A. Zambelli”Università di SalernoVia G. Paolo II, 132Fisciano84084 SAItaly
| | - Francesco F. Summa
- Department of Chemistry and Biology “A. Zambelli”Università di SalernoVia G. Paolo II, 132Fisciano84084 SAItaly
| | - Riccardo Zanasi
- Department of Chemistry and Biology “A. Zambelli”Università di SalernoVia G. Paolo II, 132Fisciano84084 SAItaly
| | - Guglielmo Monaco
- Department of Chemistry and Biology “A. Zambelli”Università di SalernoVia G. Paolo II, 132Fisciano84084 SAItaly
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2
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Đorđević S, Radenković S. Electronic structure, stability, and aromaticity of M 2B 6 (M = Mg, Ca, Sr, and Ba): an interplay between spin pairing and electron delocalization. Phys Chem Chem Phys 2022; 24:5833-5841. [PMID: 35225998 DOI: 10.1039/d1cp04791d] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
It has been shown in previous studies that the Be2B6 complex exhibits a triplet ground state with double aromaticity. In this work, the stability, electronic structure, and aromaticity of the homologous series M2B6 (M = Mg, Ca, Sr and Ba) were examined and compared to those of Be2B6. At the CCSD(T)/def2-TZVP//B3LYP/def2-TZVP level of theory, the target molecules were found to be more stable in the singlet than in the triplet spin state. Magnetically induced current densities and multicentre delocalization index (MCI) were employed to assess the aromatic character of the studied complexes. Both employed methods agree that M2B6 (M = Mg, Ca, Sr and Ba) are π aromatic and σ nonaromatic in the singlet ground state, and double aromatic in the triplet state. It was demonstrated that the electron counting rules of aromaticity cannot be used to correctly predict the aromaticity and relative stability of the examined molecules in different spin states.
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Affiliation(s)
- Slađana Đorđević
- University of Kragujevac, Faculty of Science, P. O. Box 60, 34000 Kragujevac, Serbia.
| | - Slavko Radenković
- University of Kragujevac, Faculty of Science, P. O. Box 60, 34000 Kragujevac, Serbia.
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Radenković S, Đorđević S. Spatial and electronic structures of BeB8 and MgB8. How far the analogy goes? Chemphyschem 2022; 23:e202200070. [PMID: 35188320 DOI: 10.1002/cphc.202200070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/18/2022] [Indexed: 11/09/2022]
Abstract
Doping of boron clusters with Be and its heavier alkaline-earth congener, Mg usually leads to complexes of different geometry and electronic structure. In this work we showed that both neutral BeB 8 and MgB 8 exhibit a singlet ground state umbrella-like form. In addition, the stability, electronic structure, and aromaticity of the target molecules were compared. The magnetically induced current densities showed that BeB 8 and MgB 8 are double aromatic systems: π and σ electrons induce strong diatropic currents. The current densities induced in the studied complexes are of very similar intensity, but with a different spatial distribution. The found differences between the current density patterns in BeB 8 and MgB 8 arise from the very nature of the bonding interactions between the M atom and B 8 fragment, as demonstrated through the energy decomposition analysis (EDA).
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Affiliation(s)
- Slavko Radenković
- University of Kragujevac: Univerzitet u Kragujevcu, Department of Chemistry, 12 Radoja Domanovića, P.O. Box 60, 34000, Kragujevac, SERBIA
| | - Slađana Đorđević
- University of Kragujevac: Univerzitet u Kragujevcu, Department of Chemistry, SERBIA
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Clustering of Electron Deficient B‐ and Be‐Containing Analogues: In the Fight for Tetracoordination, Beryllium Takes the Lead. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Abyaz B, Mahdavifar Z, Schreckenbach G, Gao Y. Prediction of beryllium clusters (Be n; n = 3-25) from first principles. Phys Chem Chem Phys 2021; 23:19716-19728. [PMID: 34524334 DOI: 10.1039/d1cp02513a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Evolutionary searches using the USPEX method (Universal Structure Predictor: Evolutionary Xtallography) combined with density functional theory (DFT) calculations were performed to obtain the global minimum structures of beryllium (Ben, n = 3-25) clusters. The thermodynamic stability, optoelectronic and photocatalytic properties as well as the nature of bonding are considered for the most stable clusters. It is found that the cluster with n = 15 is the transition point at which the configurations change from 3D hollow cages to filled cage structures (with an interior atom appearing in the structure). All the ground state structures are energetically favorable with negative binding energies, suggesting good synthetic feasibility for these structures. The calculated relative stabilities and electronic structure show that the Be4, Be10 and, Be17 clusters are the most stable structures and can be considered as superatoms. The electron configurations of Be4, Be10 and Be17 clusters with 8, 20 and 34 electrons are identified as 1S2 1P6, 1S2 1P6 1D10 2S2, 1S2 1P6 1D10 2S2 1F14, respectively. Theoretical simulations determined that all the ground state structures exhibit excellent thermal stability, where the upper-limit temperature that the structures can tolerate is 900 K. During AIMD simulation of O2 adsorption onto the Be17 cluster an interesting phenomenon was happening in which the pristine Be17 cluster becomes a new stable Be17O16 cluster. Based on ELF (electron localization function) analysis, it can be concluded that the Be-Be bonds in the small clusters are primarily of van der Waals type, while for the larger clusters, the bonds are of metallic nature. The Ben clusters show very strong absorption in the UV and visible regions with absorption coefficients larger than 105 cm-1, which suggests a wide range of potential advanced optoelectronics applications. The Be17 cluster has a suitable band alignment in the visible-light excitation region which will produce enhanced photocatalytic activities (making it a promising material for water splitting).
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Affiliation(s)
- Behnaz Abyaz
- Department of Chemistry, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
| | - Zabiollah Mahdavifar
- Department of Chemistry, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
| | - Georg Schreckenbach
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada
| | - Yang Gao
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.,Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China
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6
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Radenković S, Đorđević S. Relating nucleus independent chemical shifts with integrated current density strengths. Phys Chem Chem Phys 2021; 23:11240-11250. [PMID: 33949527 DOI: 10.1039/d1cp00784j] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Indices based on the nucleus independent chemical shift (NICS) are the most frequently used in analysis of magnetic aromaticity. The magnetically induced current density, on the other hand, is a key concept in defining magnetic aromaticity. The integrated current strength (current strength susceptibility) was found to be a very useful tool in aromaticity studies. There is widely accepted notion that the properly chosen NICS-based index can provide information on the current density strength and direction in a molecule of interest. In this work, a detailed numerical testing of the relationship between the integrated bond current strength and the most employed NICS indices was performed for a set of 43 monocyclic aromatic molecules. Based on the statistical data analysis, the relationship between the bond current strength and its π and σ electron components, on one side, and the isotropic NICS (NICSiso and NICSπ,iso) and zz-component of the NICS tensor (NICSzz and NICSπ,zz), on the other side, was examined. It was found that between the NICSπ,zz(1) and π-electron bond current strenghts there is very good linear correlation. Quite surprisingly, it was revealed that the NICSiso(1) and NICSzz(1) are not correlated with the π electron bond current strengths. On the other hand, a reasonably good linear correlation was found between the NICSzz(1) and total bond current strengths.
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Affiliation(s)
- Slavko Radenković
- Faculty of Science, University of Kragujevac, P. O. Box 60, 34000 Kragujevac, Serbia.
| | - Slađana Đorđević
- Faculty of Science, University of Kragujevac, P. O. Box 60, 34000 Kragujevac, Serbia.
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Monaco G, Summa FF, Zanasi R. Program Package for the Calculation of Origin-Independent Electron Current Density and Derived Magnetic Properties in Molecular Systems. J Chem Inf Model 2020; 61:270-283. [PMID: 33347314 DOI: 10.1021/acs.jcim.0c01136] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present SYSMOIC, a program package for the calculation of the origin-independent current density induced at first order by an external magnetic field in planar and nonplanar molecular systems. Origin independence is obtained adopting the continuous transformation of the origin of the current density method, implemented at both density functional theory (DFT) and Hartree-Fock (HF) levels. Expansion coefficients for perturbed and unperturbed molecular orbitals, over basis sets containing up to m-type Gaussian functions, can be calculated by the package itself or obtained from a Gaussian calculation. A number of different functionalities presented so far in the literature that are connected to the induced current, such as current density maps for any orientation of the inducing magnetic field, net bond current strengths, stagnation graphs, magnetic shielding densities, vorticities, and anisotropies, are now made available all together in a single multiplatform package installation.
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Affiliation(s)
- Guglielmo Monaco
- Dipartimento di Chimica e Biologia "A. Zambelli", Università degli Studi di Salerno, via Giovanni Paolo II 132, Fisciano 84084 SA, Italy
| | - Francesco F Summa
- Dipartimento di Chimica e Biologia "A. Zambelli", Università degli Studi di Salerno, via Giovanni Paolo II 132, Fisciano 84084 SA, Italy
| | - Riccardo Zanasi
- Dipartimento di Chimica e Biologia "A. Zambelli", Università degli Studi di Salerno, via Giovanni Paolo II 132, Fisciano 84084 SA, Italy
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Theoretical investigation on anti-sandwich beryllium-boron clusters Be2B (m = 1–3): Fluxionality and multi-aromaticity. COMPUT THEOR CHEM 2020. [DOI: 10.1016/j.comptc.2020.112949] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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9
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Đorđević S, Radenković S. Singlet and triplet states of the sandwich-type Be 2B 6 and Be 2B 7+ clusters. A test for the electron counting rules of aromaticity. NEW J CHEM 2020. [DOI: 10.1039/d0nj04643d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The studied complexes exhibit double aromaticity in their triplet states in line with the predictions of Hückel and Baird's rules.
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Affiliation(s)
- Slađana Đorđević
- University of Kragujevac
- Faculty of Science
- 34000 Kragujevac
- Serbia
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Wang YJ, Miao CQ, Xie JJ, Wei YR, Ren GM. Be2B6 and Be2B7+: two double aromatic inverse sandwich complexes with spin-triplet ground state. NEW J CHEM 2019. [DOI: 10.1039/c9nj02819f] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Be2B6 and Be2B7+ clusters adopt interesting inverse sandwich structures with double σ/π aromaticity, and the former possesses the smallest monocyclic boron ring motif.
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Affiliation(s)
- Ying-Jin Wang
- Department of Chemistry
- Xinzhou Teachers University
- Xinzhou 034000
- China
| | - Chang-Qing Miao
- Department of Chemistry
- Xinzhou Teachers University
- Xinzhou 034000
- China
| | - Jing-Jing Xie
- Department of Chemistry
- Xinzhou Teachers University
- Xinzhou 034000
- China
| | - Ya-Ru Wei
- Department of Chemistry
- Xinzhou Teachers University
- Xinzhou 034000
- China
| | - Guang-Ming Ren
- Department of Chemistry
- Xinzhou Teachers University
- Xinzhou 034000
- China
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