Nuclear Density Functional Theory Research Articles

Capturing Mercury-197m/g for Auger Electron Therapy and Cancer Theranostic with Sulfur-Containing Cyclen-Based Macrocycles.

The interest in mercury radioisotopes, 197mHg (t1/2 = 23.8 h) and 197gHg (t1/2 = 64.14 h), has recently been reignited by the dual diagnostic and therapeutic nature of their nuclear decays. These isotopes emit γ-rays suitable for single photon emission computed tomography imaging and Auger electrons which can be exploited for treating small and metastatic tumors. However, the clinical utilization of 197m/gHg radionuclides is obstructed by the lack of chelators capable of securely binding them to tumor-seeking vectors. This work aims to address this challenge by investigating a series of chemically tailored macrocyclic platforms with sulfur-containing side arms, namely, 1,4,7,10-tetrakis[2-(methylsulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane (DO4S), 1,4,7-tris[2-(methylsulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane (DO3S), and 1,7-bis[2-(methylsulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane-4,10-diacetic acid (DO2A2S). 1,4,7,10-Tetrazacyclododecane-1,4,7,10-tetracetic acid (DOTA), the widest explored chelator in nuclear medicine, and the nonfunctionalized backbone 1,4,7,10-tetrazacyclododecane (cyclen) were considered as well to shed light on the role of the sulfanyl arms in the metal coordination. To this purpose, a comprehensive experimental and theoretical study encompassing aqueous coordination chemistry investigations through potentiometry, nuclear magnetic resonance (NMR) spectroscopy, X-ray crystallography, and density functional theory (DFT) calculations, as well as concentration- and temperature-dependent [197m/gHg]Hg2+ radiolabeling and in vitro stability assays in human serum was conducted. The obtained results reveal that the investigated chelators rapidly complex Hg2+ in aqueous media, forming extremely thermodynamically stable 1:1 metal-to-ligand complexes with superior stabilities compared to those of DOTA or cyclen. These complexes exhibited 6- to 8-fold coordination environments, with donors statically bound to the metal center, as evidenced by the presence of 1H-199Hg spin-spin coupling via NMR. A similar octacoordinated environment was also found for DOTA in both solution and solid state, but in this case, multiple slowly exchanging conformers were detected at ambient temperature. The sulfur-rich ligands quantitatively incorporate cyclotron-produced [197m/gHg]Hg2+ under relatively mild reaction conditions (pH = 7 and T = 50 °C), with the resulting radioactive complexes exhibiting decent stability in human serum (up to 75% after 24 h). By developing viable chelators and understanding the impact of structural modifications, our research addresses the scarcity of suitable chelating agents for 197m/gHg, offering promise for its future in vivo application as a theranostic Auger-emitter radiometal.

Extended Fayans energy density functional: optimization and analysis

Abstract The Fayans energy density functional (EDF) has been very successful in describing global nuclear properties (binding energies, charge radii, and especially differences of radii) within nuclear density functional theory. In a recent study, supervised machine learning methods were used to calibrate the Fayans EDF. Building on this experience, in this work we explore the effect of adding isovector pairing terms, which are responsible for different proton and neutron pairing fields, by comparing a 13D model without the isovector pairing term against the extended 14D model. At the heart of the calibration is a carefully selected heterogeneous dataset of experimental observables representing ground-state properties of spherical even-even nuclei. To quantify the impact of the calibration dataset on model parameters and the importance of the new terms, we carry out advanced sensitivity and correlation analysis on both models. The extension to 14D improves the overall quality of the model by about 30%. The enhanced degrees of freedom of the 14D model reduce correlations between model parameters and enhance sensitivity.

Nuclear charge radii of germanium isotopes around N = 40

Collinear laser spectroscopy measurements were performed on 68−74Ge isotopes (Z=32) at ISOLDE-CERN, by probing the 4s24p2P13→4s24p5sP1o3 atomic transition (269 nm) of germanium. Nuclear charge radii are determined via the measured isotope shifts, revealing a larger local variation than the neighboring isotopic chains. Nuclear density functional theory with the Fayans functionals Fy(Δr,HFB) and Fy(IVP), and the SV-min Skyrme describes the experimental data for the differential charge radii δ〈r2〉 and charge radii Rc within the theoretical uncertainties. The observed large variation in the charge radii of germanium isotopes is better accounted for by theoretical models incorporating ground state quadrupole correlations. This suggests that the polarization effects due to pairing and deformation contribute to the observed large odd-even staggering in the charge radii of the Ge isotopic chain.

Ion Dynamics at the Intermediate Charging State of the Sodium Vanadium Fluorophosphate Cathode.

Na super ionic conductor (NASICON)-type polyanionic vanadium fluorophosphate Na3V2O2(PO4)2F (NVOPF) is a promising cathode material for high-energy sodium-ion batteries. The dynamic diffusion and exchange of sodium ions in the lattice of NVOPF are crucial for its electrochemical performance. However, standard characterizations are mostly focused on the as-synthesized material without cycling, which is different from the actual battery operation conditions. In this work, we investigated the hopping processes of sodium in NVOPF at the intermediate charging state with 23Na solid-state nuclear magnetic resonance (ssNMR) and density functional theory (DFT) calculations. Our experimental characterizations revealed six distinct sodium coordination sites in the intermediate structure and determined the exchange rates among these sites at variable temperatures. The theoretical calculations showed that these dynamic processes correspond to different ion transport pathways in the crystalline lattice. Our combined experimental and theoretical study uncovered the underlying mechanisms of the ion transport in cycled NVOPF and these understandings may help the optimization of cathode materials for sodium-ion batteries.

Pillarurilarenes: Glycoluril-Expanded Pillararenes.

Glycoluril-expanded pillararenes composed of glycoluril and dialkoxybenzene units, namely, pillarurilarenes (PURA), were synthesized through a fragment coupling macrocyclization strategy. Partial replacement of dialkoxybenzene with glycoluril endows PURA with polarized equatorial methine protons for derivatization or CH-anion binding. Crystal structures of pillar[2]uril[4]arene and pillar[1]uril[4]arene containing two glycoluril units and one glycoluril unit, respectively, indicated the inward orientation of the glycoluril unit, as also suggested by 1H nuclear magnetic resonance and density functional theory calculation. This work lays a good foundation for expanding pillararenes using non-aromatic rings.

Excess properties and intermolecular interactions of 2-methoxyethanol + ethylenediamine binary system: Density, viscosity, spectral analyses, computational chemistry, and CO2 absorption property

To examine the fundamental physicochemical properties as well as intermolecular interactions for the 2-methoxyethanol (EGME) (1) + ethylenediamine (EDA) (2) binary system, this work systemically measured the density (ρ) and viscosity (η) values of the binary system with various mole ratios at P = 100.5 kPa and T = (298.15–318.15) K with the growth gap of 5 K. The as-measured values of the pure substances were compared with literature data. Multiple semi-empirical formulas were used to fit ρ and η values, and the absolute average deviations (AAD%) were calculated. After that, the excess molar volume (VmE), partial molar volume (V¯), apparent molar volume (Vφ), viscosity deviation (Δη), excess activation of Gibbs free energy (ΔG∗E), and several thermodynamic properties of the binary system were systemically analyzed. According to analysis results, it has been proven that the interaction exists between EGME and EDA molecules. And then, excess properties were fitted to the Redlich-Kister equation using multi-parametric nonlinear regression analyses, and standard deviations (σ) were calculated. In addition, based on various characterization methods including Raman, ultraviolet (UV), and nuclear magnetic resonance hydrogen (1H NMR) spectral analyses and density functional theory (DFT) calculation results, it is demonstrated that there is intermolecular hydrogen bonds in EGME (1) + EDA (2) binary system as the form of –OH⋯NH2–, which was consistent with the existence forms of intermolecular hydrogen bonds in different alcohol-amine systems from references. Finally, CO2 absorption capacity by pure EDA, pure EGME, and the EGME (1) + EDA (2) binary system were severally determined.

Quantum simulation approach to implementing nuclear density functional theory via imaginary time evolution

Quantum simulation approach to implementing nuclear density functional theory via imaginary time evolution

Dual channel chemosensor for successive detection of environmentally toxic Pd2+ and CN− ions and its application to cancer cell imaging

BackgroundDetecting and neutralizing Pd2+ ions are a significant challenge due to their cytotoxicity, even at low concentrations. To address this issue, various chemosensors have been designed for advanced detection systems, offering simplicity and the potential to differentiate signals from different analytes. Nonetheless, these chemosensors often suffer from limited emission response and complex synthesis procedures. As a result, the tracking and quantification of residual palladium in biological systems and environments remain challenging tasks, with only a few chemosensing probes available for commercial use. ResultsIn this paper, a straightforward approach for the selective detection of Pd2+ ions is proposed, which involves the design, synthesis, and utilization of a propargylated naphthalene-derived probe (E)-N'-((2-(prop-2-yn-1-yloxy)naphthalen-1-yl)methylene)benzohydrazide (NHP). The NHP probe exhibits sensitive dual-channel colorimetry and fluorescence Pd2+ detection over other tested metal ions. The detection process is performed through a catalytic depropargylation reaction, followed by an excited state intramolecular proton transfer (ESIPT) process, the detection limit is as low as 11.58 × 10−7 M under mild conditions. Interestingly, the resultant chemodosimeter adduct (E)-N'-((2-hydroxynaphthalen-1-yl)methylene)benzohydrazide (NHH) was employed for the consecutive detection of CN− ions, exhibiting an impressive detection limit of 31.79 × 10−8 M. Validation of both detection processes was achieved through 1H nuclear magnetic resonance and density functional theory calculations. For real-time applications of the NHP and NHH probes, smartphone-assisted detection, and intracellular detection of Pd2+ and CN− ions within HeLa cells were studied. SignificanceThis research presents a novel naphthalene derivative for visually detecting environmentally toxic Pd2+ and CN− ions. The synthesized probe selectively binds to Pd2+, forming a chemodosimeter. It successfully detects CN− ions through colorimetry and fluorimetry, offering a low detection limit and quick response. Notably, it's the first naphthalene-based small molecule to serve as a dual probe for toxic analytes - palladium and cyanide. Moreover, it effectively detects Pd2+ and CN− intracellularly in cancer cells.

Synthesis, anticancer, anti‐inflammatory, antimicrobial activities, molecular docking, and Density functional theory studies of nanometal (IV) glycoconjugates

Oxovanadium (IV) and diphenyltin (IV) complexes were synthesized on the nanoscale based on the Schiff base (H2L) derived from salicylaldehyde and d‐glucosamine. The complexes were formed with a molar ratio of 1:1 and 1:2 (metal: dligand) relative to oxovanadium (IV) and diphenyltin (IV), respectively. Fourier‐transform infrared spectroscopy, 1H and 13C nuclear magnetic resonance, mass fragmentations, electronic transitions, thermogravimetric analysis, and density functional theory were employed to validate the structure of synthesized compounds. The results demonstrated that the ligand (H2L) was successfully attached to oxovanadium (IV) and diphenyltin (IV) as di‐anionic and mono‐anionic ligands, respectively. The size of the complexes was investigated using the transmission scanning microscope. The work presents a prospective concept for the drug design of the targeted anticancer through the glucose moiety. All compounds revealed remarkable anticancer activities against the colorectal (HCT‐116) cell line, recording IC50 values 4.94, 21.73, and 62.5 μg/ml for VO (II)(L), free H2L, and Sn (ph)2(HL)2, respectively. The IC50 value of VO (II)(L) complex was increased after the quercetin inhibitor. Therefore, the sugar‐conjugated compound can be recognized by the glucose recognition binding site of GLUT and their cell‐killing effect depends highly on the GLUT inhibitor, quercetin. The potential GLUT transportability of the compounds was investigated through a molecular docking study. The anti‐migration activity was investigated for VO (II)(L) complex. The free ligand observed the best antimicrobial results. The antibacterial stimulation was investigated and represented different interaction types with the selected ribosyl transferase enzyme.

Density, viscosity, excess properties, and intermolecular interaction of propylene glycol methyl ether + 1,2-propylenediamine binary system

In this work, the systematic measurements of physicochemical properties, viz., density (ρ) and viscosity (η) values of propylene glycol methyl ether (PGME) + 1,2-propylenediamine (1,2-PDA) binary system, including pure substances, over the entire mole fraction range at the temperatures of T/K = (298.15 to 318.15) under atmospheric pressure of P = 100.5 kPa. The fundamental data were used to calculate several excess properties, including excess molar volume (VmE), viscosity deviation (Δη), and excess activation Gibbs free energy (ΔG∗E). Meanwhile, the work further investigated the values of thermal expansion coefficient (αp), partial molar volume (V¯) and apparent molar volume (Vφ), thereby offering a comprehensive understanding on non-ideal behavior of the binary system. Furthermore, the variations in ρ values with various molar ratios and temperatures were evaluated through Jouyban-Acree model and nonlinear least squares method. Simultaneously, Grunberg-Nissan model, Eyring-Margules model, Heric model, and McAllister model, were used to fit the dependence of η values on the molar ratio. Arrhenius equation was employed to fit the temperature dependency of η values. In addition, Redlich-Kister (R-K) equation was utilized to fit the VmE, Δη, and ΔG∗E values of binary system. Based on spectral analyses of Raman, ultra-violet (UV), and 1H Nuclear Magnetic Resonance (NMR) and density functional theory (DFT) calculation, the intermolecular hydrogen bond (IHB) of PGME with 1,2-PDA was discussed in depth.

Diphosphine-Protected IrAu12 Superatom with Open Site(s): Synthesis and Programmed Stepwise Assembly.

One or two phenylacetylide (PA) ligand(s) were successfully removed from the IrAu12 superatomic core of [IrAu12(dppe)5(PA)2]+ (dppe=1,2-bis(diphenylphosphino)ethane) by reaction with controlled amounts of tetrafluoroboric acid. Optical and nuclear magnetic resonance spectroscopies and density functional theory calculations revealed the formation of open Au site(s) on the IrAu12 core of [IrAu12(dppe)5(PA)1]2+ and [IrAu12(dppe)5]3+ with the remaining structure intact. Isocyanide was efficiently trapped at the open electrophilic site on [IrAu12(dppe)5(PA)1]2+, whereas a dimer or trimer of the IrAu12 superatoms was formed using diisocyanide as a linker. These results open the door to designed assembly of chemically modified metal superatoms.

Diphosphine‐Protected IrAu12 Superatom with Open Site(s): Synthesis and Programmed Stepwise Assembly

AbstractOne or two phenylacetylide (PA) ligand(s) were successfully removed from the IrAu12 superatomic core of [IrAu12(dppe)5(PA)2]+ (dppe=1,2‐bis(diphenylphosphino)ethane) by reaction with controlled amounts of tetrafluoroboric acid. Optical and nuclear magnetic resonance spectroscopies and density functional theory calculations revealed the formation of open Au site(s) on the IrAu12 core of [IrAu12(dppe)5(PA)1]2+ and [IrAu12(dppe)5]3+ with the remaining structure intact. Isocyanide was efficiently trapped at the open electrophilic site on [IrAu12(dppe)5(PA)1]2+, whereas a dimer or trimer of the IrAu12 superatoms was formed using diisocyanide as a linker. These results open the door to designed assembly of chemically modified metal superatoms.

In-situ adsorption and detoxification of chemical warfare agent simulants by biocompatible Zr-MOFs immobilized ionic liquids composites: Mechanisms, degradation pathways and DFT calculations

Detoxicating materials of chemical warfare agents (CWAs) and their simulants play a critical role in reducing pollution contamination and environmental renovation. In this work, we present a simple strategy to prepare a core–shell structure Fe3O4/UiO-66-NH2/ILs@mSiO2 using hydrogen bonding association and electrostatic forces. We performed disinfection studies on dimethyl 4-nitrophenyl phosphate (DMNP) and 2-chloroethyl ethyl sulfide (2-CEES). The synergistic effects of catalytic activations for CWAs, which reduce the electron transport distance and lower the reaction energy barrier, lead to an increase in hydrolysis and Fenton-like reactions efficiency. Eliminationing tests of DMNP and 2-CEES showed that the half-lives of the degradation reactions were 128.36 and 1.12 min, respectively, and the degradation efficiency did not decrease significantly after 4 cycles. This new type of structure could be magnetically separated within 60 s to facilitate material recovery and reuse. Moreover, the presence of a mesoporous silica shell made the catalyst particles to become biocompatible and environmentally friendly. The degradation pathways of the intermediates were revealed based on nuclear magnetic resonance spectroscopy (NMR), gaschromatography-mass spectrometry (GC–MS) and density functional theory (DFT) calculations. The effective combination of catalysts provided a facile strategy for developing multi-effect synergistic catalysts for the elimination of CWAs and other pollutants.

The Role of Attractive Non-Covalent Interactions in Peptide Macrocyclization.

The efficiency of macrocyclization reactions relies on the appropriate conformational preorganization of a linear precursor, ensuring that reactive ends are in spatial proximity prior to ring closure. Traditional peptide cyclization approaches that reduce the extent of terminal ion pairing often disfavor cyclization-conducive conformations and can lead to undesired cyclodimerization or oligomerization side reactions, particularly when they are performed without high dilution. To address this challenge, synthetic strategies that leverage attractive noncovalent interactions, such as zwitterionic attraction between chain termini during macrocyclization, offer a potential solution by reducing the entropic penalty associated with linear peptides adopting precyclization conformations. In this study, we investigate the role of (N-isocyanoimino)triphenylphosphorane (Pinc) in facilitating the cyclization of linear peptides into conformationally rigid macrocycles. The observed moderate diastereoselectivity is consistent with the preferential Si-facial addition of Pinc, where the isocyanide adds to the E-iminium ion on the same face as the l-proline amide group. The resulting peptide chain reveals that the activated phosphonium ylide of Pinc brings the reactive ends close together, promoting cyclization by enclosing the carboxylate within the interior of the pentapeptide and preventing the formation of byproducts. For shorter peptides with modified peptide backbones, the cyclization mechanism and outcome are redirected, as nucleophilic motifs such as thiazole and imidazole can covalently trap nitrilium intermediates. The isolation of the intermediate in the unproductive macrocyclization pathway, along with nuclear magnetic resonance and density functional theory studies, provides insights into heterocycle-dependent selectivity. The Pinc-driven macrocyclization process has generated diverse collections of cyclic molecules, and our models offer a comprehensive understanding of observed trends, facilitating the development of other heterocycle-forming macrocyclization reactions.

The Synergy between Nuclear Magnetic Resonance and Density Functional Theory Calculations.

This paper deals with the synergy between Nuclear Magnetic Resonance (NMR) spectroscopic investigations and DFT calculations, mainly of NMR parameters. Both the liquid and the solid states are discussed here. This text is a mix of published results supplemented with new findings. This paper deals with examples in which useful results could not have been obtained without combining NMR measurements and DFT calculations. Examples of such cases are tautomeric systems in which NMR data are calculated for the tautomers; hydrogen-bonded systems in which better XH bond lengths can be determined; cage compounds for which assignment cannot be made based on NMR data alone; revison of already published structures; ionic compounds for which reference data are not available; assignment of solid-state spectra and crystal forms; and the creation of libraries for biological molecules. In addition to these literature cases, a revision of a cage structure and substituent effects on pyrroles is also discussed.

An NMR crystallographic characterisation of solid (+)-usnic acid.

We use a combination of one- and two-dimensional solid-state nuclear magnetic resonance (NMR) spectroscopy and density functional theory (DFT) calculations to obtain a full assignment of the 1H and 13C signals for solid (+)-usnic acid, which contains two molecules in the asymmetric unit. By combining through-space 1H-1H correlation data with computation it is possible to assign signals not just to the same molecules (relative assignment) but to assign the signals to specific crystallographic molecules (absolute assignment). Variable-temperature measurements reveal that there is some variation in many of the 13C chemical shifts with temperature, likely arising from varying populations of different tautomeric forms of the molecule. The NMR spectrum of crystalline (+)-usnic acid is then compared with that of ground Usnea dasopoga lichen (the source material of the usnic acid). The abundance of usnic acid is so great in the lichen that this natural product can be observed directly in the NMR spectrum without further purification. This natural sample of usnic acid appears to have the same crystalline form as that in the pure commercial sample.

Direct Electroreduction of Carbonate to Formate

A cause of losses in energy and carbon conversion efficiencies during the electrochemical CO2 reduction reaction (eCO2RR) can be attributed to the formation of carbonates (CO3 2–), which is generally considered to be an electrochemically-inert species. Herein, we employ in-situ electrochemical Raman spectroscopy, liquid chromatography, nuclear magnetic resonance spectroscopy, 13C isotope-labelling and density functional theory (DFT) simulations to understand the role of carbonate species formed on copper catalysts during eCO2RR, and its ability to reduce to formate. Direct carbonate-to-formate conversion was confirmed by the the direct reduction of CuCO3, and by pulse reduction of N2-saturated K2CO3 electrolyte on Cu,. DFT simulations elucidated the nature of the active sites generating the Cu-CO3 2– species and revealed the mechanism for the pulse-enabled carbonate reduction to formate. Combining both experimental and computational results, we proposed that a dynamic carbonate intermediate was constantly formed on Cu during eCO2RR, that further evolves to formate between –0.4 to –1.2 VRHE on Cu. Control systems using Pb, Ag and Au electrodes were also studied.

Electrolyte Mixtures and Organic Cathode Materials for Rechargeable Aluminum Batteries

Rechargeable aluminum (Al) metal batteries are an emerging energy storage technology ideal for use at a global scale: Al metal is energy dense, low cost, inherently safe, earth abundant, and highly recyclable. Despite such great promise, their technological progress has been hindered by the few electrolytes able to reversibly electrodeposit Al metal at room temperature, coupled with the limited number of positive electrode materials that are compatible with them. In this context, recent progress will be discussed in the development of electrolyte mixtures and organic cathode materials for rechargeable aluminum batteries. Chloroaluminate ionic liquid electrolytes and ionic liquid analogues prepared using mixtures of organic cations and/or neutral solvent species will be presented, which exhibit improved electrochemical properties for aluminum electrodeposition and in aluminum-graphite batteries, over temperatures ranging from ambient conditions down to -60 °C. Different organic structures will also be presented as organic cathode materials for aluminum batteries, where the effects of molecular structure on bulk energy storage properties will be discussed. Molecular-scale understanding of their ionic and electronic charge storage mechanisms will be elucidated through a combination of solid-state nuclear magnetic resonance (NMR) spectroscopy and density functional theory (DFT) calculations. Lastly, by using different electrolytes in combination with an organic cathode, it will be shown that electrolyte speciation can affect the local environments of charge-compensating ions in cycled organic electrodes. Overall, the results and analyses are aimed at developing next-generation rechargeable aluminum metal batteries for diverse energy storage applications.

Insight into the Chemical Stability of N-Heterocyclic Ammonium Groups for Anion-Exchange Polyelectrolytes

The chemical stability of cationic groups, not only related to alkaline degradation but also to electrochemical degradation at high potentials, is the key factor that limits the durability of anion exchange membranes (AEMs) and anion exchange ionomers (AEIs) [1]. In recent years, quaternary ammonium (QA) groups represented by N-heterocyclic ammonium (NHA) groups display excellent ionic conductivity and superior alkaline stability, which makes NHA groups promising candidates to be applied in AEMs and AEIs [2]. However, electrochemical degradation of NHA groups has been neglected in previous research, even though the electrochemical oxidation of phenyl QAs was found in the ionomer at the oxygen evolution potentials [3]. In short, the mechanism by which effect of substituents affects the durability of NHAs cations, including alkaline stability and electrochemical stability, is unclear yet, and NHA groups must be attached to the polymer backbones by substituents to achieve their applications.In this work, the chemical stability of NHA is comprehensively studied. To investigate the relationship between alkaline durability and structure, we report a systematic study on the alkaline stability of 24 representative NHA groups at different hydration numbers (λ). The electronic effect of substituents on NHA groups and degradation mechanisms of NHA groups are systematically investigated by 1H nuclear magnetic resonance (1H NMR) and density functional theory (DFT) calculations, showing that the NHA groups with electron-donating substituents exhibit outstanding alkaline stability and linking NHA groups with the polymer backbone via γ-position could be a rational design for highly alkaline stable AEMs and AEIs. Furthermore, a constant voltage is applied to the QAs electrolyte solution to measure the electrochemical stability by simulating the real operating environment of and AEM water electrolyzers. Compared to structural changes before and after voltage application, NHA exhibits worse stability than alkyl QAs, involving the radical degradation and electrochemical degradation. These results above give us a clearer picture while designing the polymer used for electrochemical devices, which is that a careful balance needs to be established between alkaline and electrochemical durability, especially under the high potential and harsh alkaline environment.

Predicting 51V nuclear magnetic resonance observables in molecular crystals.

Solid-state nuclear magnetic resonance (NMR) spectroscopy and quantum chemical density functional theory (DFT) calculations are widely used to characterize vanadium centers in biological and pharmaceutically relevant compounds. Several techniques have been recently developed to improve the accuracy of predicted NMR parameters obtained from DFT. Fragment-based and planewave-corrected methods employing hybrid density functionals are particularly effective tools for solid-state applications. A recent benchmark study involving molecular crystal compounds found that fragment-based NMR calculations using hybrid density functionals improve the accuracy of predicted 51V chemical shieldings by 20% relative to traditional planewave methods. This work extends the previous study, including a careful analysis of 51V chemical shift anisotropy, electric field gradient calculations, and a more extensive test set. The accuracy of planewave-corrected techniques and recently developed fragment-based methods using electrostatic embedding based on the polarized continuum model (PCM) are found to be highly competitive with previous methods. Planewave-corrected methods achieve a 34% improvement in the errors of predicted 51V chemical shieldings relative to planewave. Additionally, planewave-corrected and fragment-based calculations were performed using PCM embedding, improving the accuracy of predicted 51V chemical shielding (CS) tensor principal values by 30% and values by 15% relative to traditional planewave methods. The performance of these methods is further examined using a redox-active oxovandium complex and a common 51V NMR reference compound.