Natural Population Analysis Charges Research Articles

The Quality of Embedding Charges Is Critical for Convergence of Many-Body Expansions When BSSE Is Absent.

There is conflicting evidence in the literature concerning the benefits of charge embedding on the convergence of many-body expansions (MBEs). Using a systematic series of water and ion-water clusters of varying size, this study indicates that the effects of charge embedding can be masked by basis set superposition error (BSSE). When BSSE is removed, this study demonstrates that charge embedding can significantly accelerate MBE convergence, where the electrostatically embedded two-body method, EE-MBE(2), can often yield accuracy close to the four-body method, MBE(4). Contrary to previous studies on smaller systems, this work shows that the performance of EE-MBE is highly sensitive to the charge model, with the best performance obtained when the natural population analysis (NPA) charge model is used and generated at the same level of theory used in the subsystem and supersystem calculations. It was demonstrated that the "3c" composite method, PBEh-3c, yields NPA atomic charges that are in excellent agreement with those obtained from supersystem density functional theory calculations. The linear-scaling X-Polarization method provides a more general approach to estimating these supersystem QM atomic charges, but its performance depends on how the fragments are defined.

5-(Pyridin-3-yl)-3,4-dihydro-2H-furan-1-ium (NNKFI): a computational study of its physico-chemical properties.

Recent work on the diazonium ion metabolite of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNKDI) suggests that 5-(pyridin-3-yl)-3,4-dihydro-2H-furan-1-ium (NNKFI) may form from NNKDI via an intramolecular reaction. NNKDI is an important carcinogen whose role as an alkylating agent has received significant attention. While there is some experimental evidence supporting NNKFI's production in vitro, it has not yet been directly observed. Little is known about NNKFI's structure and reactivity. We report the first in silico examination of this ion. Our study utilized Kohn-Sham density functional theory (B3LYP/6-311G**) and coupled cluster theory (CCSD/6-31G*) to produce energy-optimized structures, vibrational normal modes and molecular orbitals for NNKFI. To gain insight into the chemical properties of this species, we calculated electrostatic potential surfaces, natural population analysis charges and local Fukui indices. We report data and results for NNKFI's cis and trans conformers. Our work confirms C5 as the preferred site for nucleophilic attack in NNKFI. Stretching motions and predicted bond lengths near O1 are consistent with a somewhat weakened carbonyl structure in this ion. Partial charges, electrostatic potential surfaces and local Fukui indices reveal delocalization of cationic charge on the furanium moiety and notable carbocation character at C5.

Formation, Structure and Reactivity of a Beryllium(0) Complex with Mgδ+-Beδ- Bond Polarization.

Attempts to create a novel Mg-Be bond by reaction of [(DIPePBDI*)MgNa]2 with Be[N(SiMe3)2]2 failed; DIPePBDI*=HC[(tBu)C=N(DIPeP)]2, DIPeP=2,6-Et2C-phenyl. Even at elevated temperatures, no conversion was observed. This is likely caused by strong steric shielding of the Be center. A similar reaction with the more open Cp*BeCl gave in quantitative yield (DIPePBDI*)MgBeCp* (1). The crystal structure shows a Mg-Be bond of 2.469(4) Å. Homolytic cleavage of the Mg-Be bond requires ΔH=69.6 kcal mol-1 (cf. CpBe-BeCp 69.0 kcal mol-1 and (DIPPBDI)Mg-Mg(DIPPBDI) 55.8 kcal mol-1). Natural-Population-Analysis (NPA) shows fragment charges: (DIPePBDI*)Mg +0.27/BeCp* -0.27. The very low NPA charge on Be (+0.62) compared to Mg (+1.21) and the strongly upfield 9Be NMR signal at -23.7 ppm are in line with considerable electron density on Be and the formal oxidation state assignment of MgII-Be0. Despite this Mgδ+-Beδ- polarity, 1 is extremely thermally stable and unreactive towards H2, CO, N2, cyclohexene and carbodiimide. It reacted with benzophenone, azobenzene, phenyl acetylene, CO2 and CS2. Reaction with 1-adamantyl azide led to reductive coupling and formation of an N6-chain. The azide reagent also inserted in the Cp*-Be bond. The inertness of 1 is likely due to bulky ligands protecting the Mg-Be unit.

Atomically Precise Nanometer‐Sized Pt Catalysts with an Additional Photothermy Functionality

AbstractAtomically precise ~1‐nm Pt nanoparticles (nanoclusters, NCs) with ambient stability are important in fundamental research and exhibit diverse practical applications (catalysis, biomedicine, etc.). However, synthesizing such materials is challenging. Herein, by employing the mixture ligand protecting strategy, we successfully synthesized the largest organic‐ligand‐protected (~1‐nm) Pt23 NCs precisely characterized with mass spectrometry and single‐crystal X‐ray diffraction analyses. Interestingly, natural population analysis and Bader charge calculation indicate an alternate, varying charge ‐layer distribution in the sandwich‐like Pt23 NC kernel. Pt23 NCs can catalyze the oxygen reduction reaction under acidic conditions without requiring calcination and other treatments, and the resulting specific and mass activities without further treatment are sevenfold and eightfold higher than those observed for commercial Pt/C catalysts, respectively. Density functional theory and d‐band center calculations interpret the high activity. Furthermore, Pt23 NCs exhibit a photothermal conversion efficiency of 68.4 % under 532‐nm laser irradiation and can be used at least for six cycles, thus demonstrating great potential for practical applications.

Atomically Precise Nanometer-Sized Pt Catalysts with an Additional Photothermy Functionality.

Atomically precise ~1-nm Pt nanoparticles (nanoclusters, NCs) with ambient stability are important in fundamental research and exhibit diverse practical applications (catalysis, biomedicine, etc.). However, synthesizing such materials is challenging. Herein, by employing the mixture ligand protecting strategy, we successfully synthesized the largest organic-ligand-protected (~1-nm) Pt23 NCs precisely characterized with mass spectrometry and single-crystal X-ray diffraction analyses. Interestingly, natural population analysis and Bader charge calculation indicate an alternate, varying charge -layer distribution in the sandwich-like Pt23 NC kernel. Pt23 NCs can catalyze the oxygen reduction reaction under acidic conditions without requiring calcination and other treatments, and the resulting specific and mass activities without further treatment are sevenfold and eightfold higher than those observed for commercial Pt/C catalysts, respectively. Density functional theory and d-band center calculations interpret the high activity. Furthermore, Pt23 NCs exhibit a photothermal conversion efficiency of 68.4 % under 532-nm laser irradiation and can be used at least for six cycles, thus demonstrating great potential for practical applications.

Oxygen locations and electronic structures of oxygenated coinage-metal clusters

The structure features and stability of MnO (M = Cu, Ag and Au; n = 2–9) clusters are investigated using the genetic algorithm combined with the density functional theory (DFT). It is found that CunO and AgnO are more inclined to 3-dimension compact structures, while the transition of AunO from 2 to 3-dimensions occurs at n = 7, in which O atoms prefer to be located on the vertexes regardless of different sizes and configurations of metal Mn cores. Due to the relativistic effect, the stability of AunO is maximum, while the AgnO are less stable, and that of CunO is in between them. The molecular dynamics simulations show that the structures of M4O can maintain integrity with only slight disturbances of individual atoms at a temperature of 300 K. But only the Au4O is stable at 500K, and the Ag4O and Cu4O have severely structural deformation. In most cases, the density of states of larger-sized MnO can be regarded as the superposition of small clusters, and distributions of the curves are in good agreement on the whole. The molecular orbitals reveal that the HOMO/LUMO orbitals are mainly distributed around the M atoms. The natural population analysis charges show that the charge-transferring direction is from M to O atoms, where the charge of O atoms exhibits odd–even oscillation behaviors, with different intensity peaks at the same n.

External electric field driven conformation transition between lithium salts and electride-like molecules: intriguing NLO switches in Li@corannulene.

The external electric field has emerged as a powerful tool for building molecular switches with excellent properties. In this work, we investigate the impact of an external electric field on the transition between lithium salt and electride-like molecule conformations in Li@corannulene. Remarkably, the distance between the Li atom and the corannulene bottom displays a sharp increase under the influence of an external electric field strength of F-z = 110 × 10-4 a.u. As the external electric field strength increases, the Li atom brings about different directions of charge transfer (CT). The natural population analysis (NPA) charge and the molecular electrostatic potential (ESP) results show that the intermolecular CT occurs from the Li atom to the corannulene with the F-z ranging from 0 to 100 × 10-4 a.u. Interestingly, when the external electric field reaches F-z = 110 × 10-4 a.u., the CT is oriented from the corannulene to the Li atom. Moreover, electron localization function (ELF) basins are presented under an F-z of 110 × 10-4 a.u., which indicates that Li@corannulene exhibits electride-like (e-⋯[Li@corannulene]+) molecules and lithiation salt (Li+[corannulene]-) under an F-z of 0 to 100 × 10-4 a.u. Significantly, the differences in charge transfer also contribute to a significant improvement in hyperpolarizabilities (βtot) during the conformation transition from lithiation salt (Li+[corannulene]-) to electride-like (e-⋯[Li@corannulene]+) molecules. This study explores the potential of Li@corannulene as a promising second-order NLO material, and the external electric field provides an efficient strategy for designing and developing NLO switching devices.

Theoretical Quantification of the Lewis Acidity of N‐Heterocyclic Iodonium Salts

AbstractThe quantitative Lewis acidity of N‐heterocyclic iod(az)olium salts is helpful for their further application in organic chemistry. The acidity scales of different N‐Heterocyclic iodonium salts (NHISs) in acetonitrile are investigated using Density functional theory (DFT) studies. There are a total of 121N‐Heterocyclic iodonium salts that have been designed by combining N‐heterocyclic and iodonium salt structures in this research. Theoretical calculations systematically established the 31P NMR chemical shifts of NHISs, and the relative Lewis acidity scale was derived. The Lewis acidity trend is analyzed and explained by the natural population analysis (NPA) charges, molecular electrostatic potential, and the interaction between the iodonium center and the N‐heterocyclic substituents. This study is expected to provide a practical quantitative theoretical scale for the understanding and design of hypervalent iodine(III) reagents with versatile Lewis acidity.

Vibrational spectroscopic analysis of 2, 3:4,5-Bis-O-(1-methylethylidene)beta-D-fructopyranose Sulfamate(Topiramate) by density functional method

2,3:4,5-Bis-O-(1-methylethylidene)-beta-D- fructopyranose sulfamate otherwise called as Topiramate is a drug used for the treatment of alcohol dependence. Topiramate is a safe and consistently efficacious medication for treating alcohol dependence. The spectroscopic properties of Topiramate are investigated by Fourier Transform Infrared (FT-IR), Fourier Transform Raman (FT-Raman), Fourier Transform Nuclear magnetic Resonsnce(FT-NMR) andUltra Violet Visible (UV–visible) spectroscopic techniques. The FTIR, FT-Raman, FT-NMR and UV–visible spectra of Topiramate have been recorded and analyzed. Theoretical vibrational frequencies, geometric parameters, thermodynamic properties, Natural population analysis and Mulliken atomic charges of Topiramateare obtained by the Restricted Hartree–Fock (RHF) and density functional theory (DFT) using 6–31 + G(d,p) basis set. The calculated harmonic vibrational frequencies for Topiramate are compared with the experimental values of FTIR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analysed using natural bond orbital (NBO) analysis. The first-order hyperpolarizability (βtot) and other related properties such as dipole moment(µ), polarizability(αo)values of the investigated molecule are computed using HF and DFT/B3LYP with 6–31 + G(d,p) basis set. The calculated results also show that the Topiramate molecule may have microscopic nonlinear optical (NLO) behaviour.

Pharmacophore Oriented MP2 Characterization of Charge Distribution for Anti-SARS-CoV-2 Inhibitor Nirmatrelvir

Quantum mechanical second order Møller–Plesset (MP2) perturbation theory and density functional theory (DFT) Becke, 3-parameter, Lee-Yang-Parr (B3LYP) and Minnesota 2006 local functional (M06L) calculations were performed to optimize structure of nirmatrelvir and compute the Merz-Kollman electrostatic potential (MK ESP), natural population analysis (NPA), Hirshfeld, charge model 5 (CM5), and mulliken partial charges. The mulliken partial charge distribution of nirmatrelvir exhibits a poor correlation with the MK ESP charges in MP2, B3LYP, and M06L calculations respectively. The NPA, Hirshfeld, and CM5 partial charge scheme of nirmatrelvir indicate a reasonable correlation with MK ESP charge assignments in B3LYP and M06L calculations. The above correlations were not improved by the inclusion of implicit solvation model. The MK ESP and CM5 partial charges show a strong correlation between the results of MP2 and two DFT methods. The three optimized structures present a certain degree of differences from the crystal bioactive conformation of nirmatrelvir, suggesting the nirmatrelvir-enzyme complex is formed in the induced-fit model. The Reactivity of warhead electrophilic nitrile is justified by the relatively weaker strength of π bonds in the MP2 calculations. The nirmatrelvir hydrogen bond acceptors consistently show strong delocalization of lone pair electrons in three calculations, whereas hydrogen bond donors are found to have high polarization on the heavy nitrogen atoms in MP2 computations. This work helps to parametrize the force field of nirmatrelvir and improve accuracy of molecular docking and rational inhibitor design.

Iridium/Zinc-Co-Catalyzed Ring-Opening Reactions of Oxabicyclic Alkenes with Indole Nucleophiles: A Combined Experimental and Theoretical Study

An experimental and theoretical investigation on the iridium/zinc-co-catalyzed ring-opening reactions of oxabicyclic alkenes with indole nucleophiles is reported. The reaction affords trans-3-indolyl-1,2-dihydronaphthalen-1-ol products in good yield with no N-alkylated products observed. The C–C bond-forming reaction does not require prior functionalization and is entirely atom-economic. The mechanism and origins of selectivity in the iridium-catalyzed ring-opening reaction have been examined at the M06-D3/Def2TZVPP level of theory. Orbital analysis and natural population analysis charges demonstrate that the Cα site of the π-allyliridium intermediate is the most electrophilic site of attack. Distortion/interaction analysis reveals that the chemoselectivity likely originates from an earlier-stage transition state between Cα and C3, which requires less distortion energy compared to Cα–N1 during the rate-determining intermolecular nucleophilic attack. Moreover, conceptual density functional theory was used to conceptualize the preferential reactive sites of the nucleophiles probed. The C–C bond-forming step is speculated to proceed through a Friedel–Crafts-type reaction.

Trinuclear and Cyclometallated Organometallic Dinuclear Pt-Pyrazolato Complexes: A Combined Experimental and Theoretical Study

Two differently substituted pyrazole ligands have been investigated with regard to the topology of their Pt complexes: upon deprotonation, two mononuclear 1:2 PtII-pyrazole complexes—one of the sterically unhindered 4-Me-pzH and one of the bulky 3,5-tBu-pzH (pzH = pyrazole)—yield the corresponding 1:2 PtII-pyrazolato species; the former a triangular, trinuclear metallacycle (1), and the latter a dinuclear, half-lantern species (2) formed via the unprecedented cyclometallation of a butyl group. Stoichiometric oxidation of the colorless PtII2 complex produces the deep-blue, metal–metal bonded PtIII2 analog (3) with a rarely encountered unsymmetrical coordination across the Pt-Pt bond. All three complexes have been characterized by single crystal X-ray structure determination, 1H-NMR, IR, and UV-vis-NIR spectroscopic methods. The XPS spectra of the PtII2 and PtIII2 species are also reported. Density functional theory calculations were carried out to investigate the electronic structure, spectroscopic properties, and chemical bonding of the new complexes. The calculated natural population analysis charges and Wiberg bonding indices indicate a weak σ-interaction in the case of 2 and a formal Pt-Pt single bond in 3.

The change of hydrogen position on π-conjugated bridge to affect NLO property of D(–NH2)-π(DHTPs)-A(–NO2) system

The donor-π-conjugated bridge-acceptor (D-π-A) is a classical framework to design high-performance organic electro-optical materials. In this work, based on the π-conjugated dihydrotetraazapentacenes (DHTPs), four isomers (1–4) with D(–NH2)-π(DHTPs)-A(–NO2) framework are designed and characterized. The 2 and 3 originate from single-hydrogen migration of 1, and 4 derives from double-hydrogen migration of 1. Significantly, the change of hydrogen position on DHTPs bridge can affect their nonlinear optics (NLO) property. Compared with the first hyperpolarizability (βtot) (4.08 × 103a.u.) of 1, the 6.90 × 103-2.56 × 104 a.u. of 2–4 are enhanced. More interestingly, the 4 has largest βtot value of 2.56 × 104, which is approximately equal to the sum of 6.90 × 103 a.u. of 2 and 1.82 × 104 a.u. of 3. Furthermore, the change of hydrogen position on DHTPs brings some distinctive changes in their geometric structure, nucleus-independent chemical shifts (NICS) value, natural population analysis (NPA) charge, UV–vis absorption spectrum along with its other electronic property that might be beneficial to explore their structure–property relationships.

Atomic chemical environment of tungsten in coal: Implication for the evolution of the germanium coal deposits

The Wulantuga, Lincang, and similar germanium deposits are abnormally enriched in organically associated Ge and W. In this study, the Density Functional Theory (DFT) calculation is employed to investigate the structure and bonding nature of W in coal, which helps for a better knowledge of the mode of occurrence of organically bound metals and the evolution of the coal-hosted Ge deposits.Five model compounds (ethanol, phenol, catechol, acetic acid, and benzoic acid) that represent all hydroxyls in coal structure are used to simulate the formation of W-O complexes. According to the binding energies and Natural Population Analysis (NPA) charges, W is preferred to be bonded with O-exposed model compounds to form stable W-O complexes. The phenolic hydroxyls are easier to break OH bond, suggesting that the fragments of catechol and phenol are more reactive. The carbon rings in coal are capable of bonding W, but there is less chance for graphene to be the binding site.The W-O complex can be coordinately saturated if W connects with three (catechol, acetic acid, and benzoic acid) or four (phenol and ethanol) O-exposed molecules. Generally, due to stronger binding energies, W is likely to form more stable complexes with hydroxyls relative to Ge. It is noted that W is preferred to be bonded with both O in each molecule of acetic acid or benzoic acid, and the W-O complex can reach saturation with three molecules in a distorted octahedral structure at the center. In contrast, Ge is tended to be bonded with one O in each molecule, and the Ge-O complex can be saturated with four molecules in a tetrahedral structure.The deposit evolution includes two stages: (1) Formation. The peat/lignite possesses abundant hydroxyls capable of capturing Ge and W from hydrothermal solutions and meteoric waters. Germanium and W can be fixed in the coal structure by O-bridged complexes until coal rank reaching lignite/subbituminous coal. (2) Redistribution. Along with coal rank advance to bituminous coal/anthracite, oxygen as heteroatom is expelled out from coal structure, and the bonding sites for Ge and W disappear as O-containing groups (especially hydroxyls) vanish. Thus, Ge and W can be liberated from coal.

Intra-ring proton transfer effect on the Structure-NLO property relationships of phthalocyanine derivatives

Based on the phthalocyanine, four models (1–4) are designed to explore the intra-ring proton transfer effect on structure–property relationships. The results show that small differences in structure bring fascinating changes in nucleus-independent chemical shifts (NICS) values, anisotropy of the induced current density (AICD), natural population analysis (NPA) charge, electrostatic potential (ESP), UV–vis absorption spectrum as well as unit sphere representation (USR). Significantly, the largest static first hyperpolarizability βtot value (1.47 × 104) of 4 is approximately 15 times larger than that (8.98 × 102 au) of 1 due to the intra-ring proton transfer regulating conjugation degree of the conjugation section. Furthermore, the dynamic first hyperpolarizability βHRS at the wavelengths λ = 1907, 1460 nm is elaborated in detail. We hope that the present work may evoke the possibility to probe into a promising field for nonlinear optics (NLO) application.

Evodiamine and Rutaecarpine as Potential Anticancer Compounds: A Combined Computational Study.

Evodiamine (EVO) and rutaecarpine (RUT) are the main active compounds of the traditional Chinese medicinal herb Evodia rutaecarpa. Here, we fully optimized the molecular geometries of EVO and RUT at the B3LYP/6-311++G (d, p) level of density functional theory. The natural population analysis (NPA) charges, frontier molecular orbitals, molecular electrostatic potentials, and the chemical reactivity descriptors for EVO and RUT were also investigated. Furthermore, molecular docking, molecular dynamics simulations, and the analysis of the binding free energies of EVO and RUT were carried out against the anticancer target topoisomerase 1 (TOP1) to clarify their anticancer mechanisms. The docking results indicated that they could inhibit TOP1 by intercalating into the cleaved DNA-binding site to form a TOP1–DNA–ligand ternary complex, suggesting that they may be potential TOP1 inhibitors. Molecular dynamics (MD) simulations evaluated the binding stability of the TOP1–DNA–ligand ternary complex. The calculation of binding free energy showed that the binding ability of EVO with TOP1 was stronger than that of RUT. These results elucidated the structure–activity relationship and the antitumor mechanism of EVO and RUT at the molecular level. It is suggested that EVO and RUT may be potential compounds for the development of new anticancer drugs.

Redox induced electron transfer in lithium polysulfide – A DFT study

This study reports the existence of redox-induced electron transfer in lithium polysulfides (RIET). The presence of redox-induced electron transfer in lithium polysulfides is confirmed using a DFT study. The sulfur gets oxidized, and lithium gets reduced during the removal of an electron from lithium polysulfides. The condensed Fukui function from Natural Population Analysis (NPA) charge and electron density augment RIET. The higher number of sulfur contributes to the total nucleophilic character of lithium polysulfide and holds lithium tightly. The presence of an electric field enhances the nucleophilicity of sulfur atoms and, hence, the reactivity of lithium polysulfides.

Chromium Nitride Umpolung Tuned by the Locus of Oxidation.

Oxidation of a series of CrV nitride salen complexes (CrVNSalR) with different para-phenolate substituents (R = CF3, tBu, NMe2) was investigated to determine how the locus of oxidation (either metal or ligand) dictates reactivity at the nitride. Para-phenolate substituents were chosen to provide maximum variation in the electron-donating ability of the tetradentate ligand at a site remote from the metal coordination sphere. We show that one-electron oxidation affords CrVI nitrides ([CrVINSalR]+; R = CF3, tBu) and a localized CrV nitride phenoxyl radical for the more electron-donating NMe2 substituent ([CrVNSalNMe2]•+). The facile nitride homocoupling observed for the MnVI analogues was significantly attenuated for the CrVI complexes due to a smaller increase in nitride character in the M≡N π* orbitals for Cr relative to Mn. Upon oxidation, both the calculated nitride natural population analysis (NPA) charge and energy of molecular orbitals associated with the {Cr≡N} unit change to a lesser extent for the CrV ligand radical derivative ([CrVNSalNMe2]•+) in comparison to the CrVI derivatives ([CrVINSalR]+; R = CF3, tBu). As a result, [CrVNSalNMe2]•+ reacts with B(C6F5)3, thus exhibiting similar nucleophilic reactivity to the neutral CrV nitride derivatives. In contrast, the CrVI derivatives ([CrVINSalR]+; R = CF3, tBu) act as electrophiles, displaying facile reactivity with PPh3 and no reaction with B(C6F5)3. Thus, while oxidation to the ligand radical does not change the reactivity profile, metal-based oxidation to CrVI results in umpolung, a switch from nucleophilic to electrophilic reactivity at the terminal nitride.

Interaction of Cysteine with Li+ and LiF in the Presence of (H2O) n (n = 0-6) Clusters.

The interaction between cysteine with Li+ and LiF in the microcosmic water environment was investigated to elucidate how ions interact with amino acids and the cation–anion correlation effect involved. The structures of Cys·Li+(H2O)n and Cys·LiF(H2O)n (n = 0–6) were characterized using ab initio calculations. Our studies show that the water preferentially interacts with Li+/LiF. In Cys·Li+(H2O)0–6, Li+ interacts with amino nitrogen, carbonyl oxygen, and hydrophobic sulfur of Cys to form a tridentate mode, whereas in Cys·LiF(H2O)n, Li+ and F– work in cooperation and interact with carbonyl oxygen and hydroxyl hydrogen of Cys to form a bidentate type. The neutral and zwitterionic forms are essentially isoenergetic when the water number reaches three in the presence of Li+, whereas this occurs at four water molecules in the presence of LiF. Further research revealed that the interaction between Li+/LiF and Cys was mainly electrostatic, followed by dispersion, and the weakest interaction occurs at the transition from the neutral form to zwitterionic form. Natural population analysis charge analyses show that for Cys·Li+(H2O)n, the positive charge is mostly concentrated on Li+ except for the system containing three water molecules. For Cys·LiF(H2O)n, the positive charge is centered on the LiF unit in the range n = 0–6, and at n = 5, electron transfer from Cys to water occurs. Our study shows that the contribution of anions in zwitterionic state stabilization should be addressed more generally along with cations.

Plasma-Assisted Dinitrogen Activation via Dual Platinum Cluster Catalysis: A Strategy for Ammonia Synthesis under Mild Conditions

Plasma-Assisted Dinitrogen Activation via Dual Platinum Cluster Catalysis: A Strategy for Ammonia Synthesis under Mild Conditions