Single Dimer Research Articles

First-principles study of electronic and magnetic properties of Fe atoms on Cu2N/Cu(100)

Abstract First-principles calculations were conducted to investigate the structural, electronic, and magnetic properties of single Fe atoms and Fe dimers on Cu2N/Cu(100). Upon adsorption of an Fe atom onto Cu2N/Cu(100), robust Fe–N bonds form, resulting in the incorporation of both single Fe atoms and Fe dimers within the surface Cu2N layer. The partial occupancy of Fe-3d orbitals lead to large spin moments on the Fe atoms. Interestingly, both single Fe atoms and Fe dimers exhibit in-plane magnetic anisotropy, with the magnetic anisotropy energy (MAE) of an Fe dimer exceeding twice that of a single Fe atom. This magnetic anisotropy can be attributed to the predominant contribution of the component along the x direction of the spin–orbital coupling Hamiltonian. Additionally, the formation of Fe–Cu dimers may further boost the magnetic anisotropy, as the energy levels of the Fe-3d orbitals are remarkably influenced by the presence of Cu atoms. Our study manifests the significance of uncovering the origin of magnetic anisotropy in engineering the magnetic properties of magnetic nanostructures.

Nature of CuxCe1-xO2 solid solution catalysts

Identifying the local environments of active sites of CuxCe1-xO2 solid solution for low-temperature CO oxidation remains significant challenges. In this study, we coupled density functional theory and microkinetic modeling to thoroughly investigate local structures of CuxCe1-xO2 solid solution catalysts, as well as its catalytic performance for low-temperature CO oxidation. Combined with the infrared spectra simulations, we propose that the substitution of Cu3 or Cu4 clusters for one Ce atom accounts for the experimentally observed vibrational peaks of the adsorbed CO, rather than the Cu single atom or dimer. Cu single-atom and Cun clusters (n = 2–4) doped into CeO2 all exhibit an excellent stability against ripening and a promising catalytic activity for low-temperature CO oxidation. This research for the first time elucidates the nature of CuxCe1-xO2 solid solution catalysts and paves the way for the rational design of Cu/CeO2 catalysts for CO oxidation.

Ir noble metal atoms/clusters on graphene support: Insights from aberration corrected-STEM and density functional theory

The interactions of Iridium (Ir) noble metal atoms/clusters (Ir NMAs/NMCs) with graphene are investigated due to their remarkable catalytic performance, resulting from the use of 100 % metal atoms compared to nanoparticle counterparts. Using scanning transmission electron microscopy (STEM), various forms of Ir dispersed on graphene were observed, including single atoms, dimers, and trimers clusters. The STEM data further revealed inter-atomic distances of 2.83 Å and 2.96 Å for dimers and trimers which were 20 % and 17 % larger than the numbers found through density functional theory (DFT) calculations. The DFT calculations further showed that the Dirac-cone of graphene at Ir NMAs/NMCs locations changes to metallic form due to the emergence of energy states at the Fermi level. This effect results in non-zero effective masses of charge carriers but enhances their density of states (DOS) by 2-fold which is believed to increase the energy absorption efficiency of graphene in the infra-red range of radiation.

Synthesis and Dynamic Behaviors of 5,7,8,10-Tetraphenyl-1,14-dianilinotripyrrins

Abstract5,7,8,10-Tetraphenyl-1,14-di(arylamino)tripyrrins have been synthesized via 5,7,8,10-tetraphenyltripyrrane. The structures and dynamic equilibrium between single helical monomer and double helical dimer were analyzed by 1H NMR spectra and X-ray diffraction analysis. Their dimerization association constants in CDCl3 are larger than those of previously reported dianilinotripyrrin derivatives. In DMSO, they exhibited luminescence around 700 nm as a consequence of restricted rotational relaxation by the phenyl groups installed at the 7,8-positions.

A structural and dynamic visualization of the interaction between MAP7 and microtubules

Microtubules (MTs) are key components of the eukaryotic cytoskeleton and are essential for intracellular organization, organelle trafficking and mitosis. MT tasks depend on binding and interactions with MT-associated proteins (MAPs). MT-associated protein 7 (MAP7) has the unusual ability of both MT binding and activating kinesin-1-mediated cargo transport along MTs. Additionally, the protein is reported to stabilize MTs with its 112 amino-acid long MT-binding domain (MTBD). Here we investigate the structural basis of the interaction of MAP7 MTBD with the MT lattice. Using a combination of solid and solution-state nuclear magnetic resonance (NMR) spectroscopy with electron microscopy, fluorescence anisotropy and isothermal titration calorimetry, we shed light on the binding mode of MAP7 to MTs at an atomic level. Our results show that a combination of interactions between MAP7 and MT lattice extending beyond a single tubulin dimer and including tubulin C-terminal tails contribute to formation of the MAP7-MT complex.

High Electric Field Enhancement Induced by Modal Coupling for a Plasmonic Dimer Array on a Metallic Film

A giant electric field on a subwavelength scale is highly beneficial for boosting the light–matter interaction. In this paper, we investigated a hybrid structure consisting of a hemispheric dimer array and a gold film and realized resonant mode coupling of the surface lattice resonance (SLR) and surface plasmon polariton (SPP). Mode coupling is demonstrated by observing anti-crossing in reflection spectra, which corresponds to Rabi splitting. Although the resonance coupling does not enter the strong coupling regime, an improved quality factor (Q~350) and stronger electric field enhancement in the gap region of the dimer (i.e., hot spot) in our hybrid structure are obtained compared to those of the single dimer or dimer array only. Remarkably, the magnitude of electric field enhancement over 500 can be accessible. Such high field enhancement makes our hybridized structure a versatile platform for the realization of ultra-sensitive biosensing, low-threshold nanolasing, low-power nonlinear optical devices, etc.

Electromagnetic enhancement spectra of one-dimensional plasmonic hotspots along silver nanowire dimer derived via surface-enhanced fluorescence.

We developed a spectroscopic method for directly obtaining the spectra of electromagnetic (EM) enhancement of plasmonic hotspots (HSs). The method was applied to one-dimensional (1D) HSs generated between silver nanowire (NW) dimers. The EM enhancement spectra were derived by dividing the spectra of surface-enhanced fluorescence (SEF) from single NW dimers with SEF obtained from large nanoparticle aggregates, where aggregate-by-aggregate variations in the SEF spectra were averaged out. Some NW dimers were found to exhibit EM enhancement spectra that deviated from the plasmon resonance Rayleigh scattering spectra, indicating that their EM enhancement was not generated by superradiant plasmons. These experimental results were examined by numerical calculation based on the EM mechanism by varying the morphology of NW dimers. The calculations reproduced the spectral deviations as the NW diameter dependence of EM enhancement. Phase analysis of the enhanced EM near-fields along the 1D HSs revealed that the dipole-quadrupole coupled plasmon, which is a subradiant mode, mainly generates EM enhancement for dimers with NW diameters larger than ∼80nm, which was consistent with scanning electron microscopic measurements.

Charge State of Au Atoms on an Oxidized Rutile TiO2(110) Surface by AFM/KPFM at 78 K.

The charge state of noble metal atoms on a semiconductor surface is an important factor in surface catalysis. In this study, Au atoms were deposited on the rutile TiO2(110) surface to characterize its charge properties using atomic force microscopy with Kelvin probe force microscopy at 78 K. Au single atoms, dimers, and trimers at different sites on the surface were investigated. Positively charged Au atoms were verified at oxygen sites, while negatively charged Au atoms were found near oxygen vacancy sites. Furthermore, the charge states of small Au nanoclusters were clarified. Understanding the charge states of Au atoms is significant for identifying their efficient catalytic effects in surface catalysis.

Characterization of Chiral Near Field Within Nanogaps Using Surface‐Enhanced Raman Scattering

AbstractChiral nanogap antennas, which exhibit specific chiroptical responses, hold exceptional potential in various chiral applications, including polarization converters, asymmetric catalysis, label‐free chiral recognition, and chiral sensing. However, characterizing the chiral optical fields within nanogaps presents considerable challenges owing to their complex light field responses and spatial dimensions. In this study, the strong modulation of helicity‐resolved surface‐enhanced Raman spectroscopy (SERS) signals in graphene by chiral plasmonic antennas, offering a promising approach to characterize chiral near fields within nanogaps is demonstrated. The SERS of achiral monolayer graphene is performed within plasmonic nanogap antennas, including single gold nanorods (GNRs) and GNR dimers on gold microflakes. The Raman scattering intensity of graphene within these nanogap antennas is enhanced approximately sixfold. Furthermore, the degree of cross‐circularly polarized Raman intensity reaches up to ≈45%, indicating a robust chiral optical field. Moreover, under opposite circularly polarized light excitation, the SERS of graphene reveals varying emission intensities attributed to the modulation arising from the chiral antennas in both the excitation and emission processes of Raman scattering. Furthermore, the degree of chirality depends on the antenna configuration and the excitation laser wavelength.

The Effect of Nanoparticle Composition on the Surface-Enhanced Raman Scattering Performance of Plasmonic DNA Origami Nanoantennas.

A versatile generation of plasmonic nanoparticle dimers for surface-enhanced Raman scattering (SERS) is presented by combining a DNA origami nanofork and spherical and nonspherical Au or Ag nanoparticles. Combining different nanoparticle species with a DNA origami nanofork to form DNA origami nanoantennas (DONAs), the plasmonic nanoparticle dimers can be optimized for a specific excitation wavelength in SERS. The preparation of such nanoparticle dimers is robust enough to enable the characterization of SERS intensities and SERS enhancement factors of dye-modified DONAs on a single dimer level by measuring in total several thousands of dimers from five different dimer designs, each functionalized with three different Raman reporter molecules and measured at four different excitation wavelengths. Based on these data, SERS enhancement factor (EF) distributions have been determined for each dimer design and excitation wavelengths. The structures and measurement conditions with the highest EFs are suitable for single-molecule SERS (SM-SERS), which is realized by placing single dye molecules into hot spots. We demonstrate that the probability of placing single molecules in a strongly enhancing hot spot for SM-SERS can be increased by using anisotropic nanoparticles with several sharp edges, such as nanoflowers. Combining a Ag nanoparticle with a Au particle in one dimer structure allows for a broadband excitation covering almost the whole visible range. The most versatile plasmonic dimer structure for SERS combines a spherical Ag nanoparticle with a Au nanoflower. Employing the discontinuous Galerkin time domain method, we numerically investigate the bare, symmetric dimers with respect to spectral and near-field properties, showing that, indeed, the nanoflowers induce multiple hot spots located at the edges which surpass the intensity of the spherical dimers, indicating the possibility for SM-SERS. The presented DONA structures and SERS data provide a robust basis for applying such designs as versatile SERS tags and as substrates for SM-SERS measurements.

Enhanced Uptake of Anticancer C6-Pep Dimer in a Model Membrane Caused by Differential pKa in Acidic Microenvironment.

Acidic tumor microenvironment (TME) presents a challenge for the action of antitumor drugs by acting as an additional barrier for the passive crossing of the cell membrane by chemotherapic agents playing a critical role in the proliferation of tumor cells. Anticancer lipopeptide C6-Pep dimer containing the leucine zipper motif shows an increased uptake into the model tumor membrane in TME, and application of external heat might lead to the uncoiling of the zipper, which could result in cell lysis. This work investigated the cause of this increased uptake of C6-Pep dimer into the bilayer model in TME. Accurate protonation states of all the titratable residues of the C6-Pep dimer in TME were determined using constant pH molecular dynamics. In TME, except for two terminal Glu5 residues, all other Glu residues in the C6-Pep dimer were permanently protonated. The remaining Glu5 residues had differential pKa values, leading to the construction of four possible dimers with different fixed protonation states, and molecular dynamics was used to study their interaction with the anionic bilayer. Except for the dimer at a physiological pH, the other dimers were positively charged and could readily adsorb on the membrane surface. The free energy of insertion of these dimers in the bilayer was lower for single and double protonated Glu5-containing dimers than for the others. After the insertion of the lipopeptides into the membrane, thinning of the bilayer in the vicinity of dimers and an increase in area per lipid of the bilayer were observed for all systems, indicating destabilization of the bilayer due to this intercalation. This study shows that the anticancer lipopeptide C6-Pep utilizes the TME around a tumor cell for insertion into the membrane.

Intermolecular and Electrode-Molecule Bonding in a Single Dimer Junction of Naphthalenethiol as Revealed by Surface-Enhanced Raman Scattering Combined with Transport Measurements.

Electron transport through noncovalent interaction is of fundamental and practical importance in nanomaterials and nanodevices. Recent single-molecule studies employing single-molecule junctions have revealed unique electron transport properties through noncovalent interactions, especially those through a π-π interaction. However, the relationship between the junction structure and electron transport remains elusive due to the insufficient knowledge of geometric structures. In this article, we employ surface-enhanced Raman scattering (SERS) synchronized with current-voltage (I-V) measurements to characterize the junction structure, together with the transport properties, of a single dimer and monomer junction of naphthalenethiol, the former of which was formed by the intermolecular π-π interaction. The correlation analysis of the vibrational energy and electrical conductance enables identifying the intermolecular and molecule-electrode interactions in these molecular junctions and, consequently, addressing the transport properties exclusively associated with the π-π interaction. In addition, the analysis achieved discrimination of the interaction between the NT molecule and the Au electrode of the junction, i.e., Au-π interactions through-π coupling and though-space coupling. The power density spectra support the noncovalent character at the interfaces in the molecular junctions. These results demonstrate that the simultaneous SERS and I-V technique provides a unique means for the structural and electrical investigation of noncovalent interactions.

UPLC-QTOF-MS/MS assisted UPLC-TQ-MS/MS strategy to comparatively investigate the rat pharmacokinetics of N-acetyldopamine oligomers derived from Cicadae Periostracum

Cicadae Periostracum (CP), the slough molted from the nymph of Cryptotympana pustulata, is a widely used medicinal material in traditional Chinese medicine (TCM). N-acetyldopamine oligomers (NAOs), the homologues of acetyldopamine, including N-acetyldopamine dimers/trimers/tetramers/pentamers (NADs/NATrs/NATes/NAPs), side-chain isomer of dimers/trimers (SCIDs/SCITrs), are major bioactive ingredients of CP. However, owing to commercially unavailable reference substances of all NAOs, simultaneous quantification of these NAOs in biological samples is difficult, and thus their pharmacokinetics are still unknown. In this study, a comprehensive strategy for simultaneous quantification/semi-quantification of NAOs in plasma with single N-acetyldopamine dimer A (NAD-A) as reference substance was established and comparatively investigated their pharmacokinetics after oral administration of pure NAD-A and two types of CP extracts, i.e., post-molting-washed slough (CP-WAT) and pre-molting-washed slough (CP-WBT). A UPLC-QTOF-MS/MS assisted UPLC-TQ-MS/MS strategy was developed to quantify NAOs in rat plasma. NAOs in CP extract were qualitatively characterized by UPLC-QTOF-MS/MS, then the quasi-molecular ions and characteristic fragment ions of the identified NAOs by UPLC-QTOF-MS/MS were transferred to UPLC-TQ-MS/MS as parent-daughter ion pairs for MRM mode quantification of the NAOs, and the method was validated with single NAD-A for quantifying NAD-A and semi-quantifying other NAOs in plasma. The established method was applied to compare the pharmacokinetics of NAOs after oral administration of NAD-A and the extracts of CP-WBT/CP-WAT respectively. Six quasi-molecular ions and characteristic fragment ion m/z 192.1 were characterized by UPLC-QTOF-MS/MS and transferred to be the parent-daughter ion pairs for UPLC-TQ-MS/MS analysis of six kinds of NAOs. For the pharmacokinetics, NAD-A showed double peaks absorption character when administered with single compound, but with higher relative bioavailability when administered with CP extracts with the similar dosage. Compared with CP-WAT, NAOs in CP-WBT reached the maximum plasma concentration in much shorter time.

Manipulating hydrogen bond dissociation rates and mechanisms in water dimer through vibrational strong coupling

The vibrational strong coupling (VSC) between molecular vibrations and cavity photon modes has recently emerged as a promising tool for influencing chemical reactivities. Despite numerous experimental and theoretical efforts, the underlying mechanism of VSC effects remains elusive. In this study, we combine state-of-art quantum cavity vibrational self-consistent field/configuration interaction theory (cav-VSCF/VCI), quasi-classical trajectory method, along with the quantum-chemical CCSD(T)-level machine learning potential, to simulate the hydrogen bond dissociation dynamics of water dimer under VSC. We observe that manipulating the light-matter coupling strength and cavity frequencies can either inhibit or accelerate the dissociation rate. Furthermore, we discover that the cavity surprisingly modifies the vibrational dissociation channels, with a pathway involving both water fragments in their ground vibrational states becoming the major channel, which is a minor one when the water dimer is outside the cavity. We elucidate the mechanisms behind these effects by investigating the critical role of the optical cavity in modifying the intramolecular and intermolecular coupling patterns. While our work focuses on single water dimer system, it provides direct and statistically significant evidence of VSC effects on molecular reaction dynamics.

Narrow resonance line-widths and high figure of merits via composite nanopillar dimer array sensors

The Ag/Si/SiO2 composite nanopillar dimer array sensor is put forward to form a surface lattice resonance (SLR) with strong intensity and narrow resonance line-width. In the Ag/Si/SiO2 composite nanopillar dimer array, Ag nanopillar dimers sit on Si nanopillar dimers, and Si nanopillar dimers sit on SiO2 nanopillar dimers, which sit on a quartz substrate. Simulated results demonstrate that the line-width can be as narrow as 2.1 nm. This is mainly attributed to the coupling between the combination of single Ag nanopillar dimers' local surface plasmon quadrupole (Q) resonance and Si nanopillar dimers' Mie resonance with the array's diffraction waves. However, for the Ag/Si/SiO2 composite nanopillar array (without dimers), the SLR intensity is too weak for the sensing applications. Compared to the Ag/Si/SiO2 composite nanopillar array, the superiority of the Ag/Si/SiO2 composite nanopillar dimer array is that the near-field coupling in the dimer can further improve Ag nanopillar dimers' Q resonance and Si nanopillar dimers' Mie resonance. Therefore, SLR intensity can be significantly enhanced with only a slight increase in line-width, thus the sensing detection range is wider. The array's period, the height and diameter of Ag/Si/SiO2 nanopillars have notable effects on the SLR. Benefiting from the narrow line-width, the figure of merit (FOM) can reach a value of 226. This work is important to improve the optical sensor based on SLRs.

Abstract 2487: Metastasis: Cancer cells that have turned on a Yamanaka-like pluripotency program

Abstract Purpose: To develop therapeutics to treat metastasis of solid tumor cancers. To overcome obstacles to developing anti-metastasis treatments by: 1) developing an animal model that reproducibly mimics cancer metastasis and does so within a reasonable timeframe; and 2) figuring out the basic science that drives metastasis. Experimental: We discovered that all pluripotent human stem cells express a MUC1 cleavage product called MUC1* (muk 1 star). All MUC1 cleavage stops with the onset of differentiation and MUC1 goes back to its quiescent state. Over 75% of solid tumor cancers also express MUC1*. Overexpression of MUC1*, as well as enzymes that cleave MUC1 to MUC1* are predictors of poor prognosis. NME1 is a ligand of MUC1* that is secreted by both embryonic stem cells and cancer cells. As a dimer, NME1 dimerizes the MUC1* extra cellular domain to activate the MAP kinase growth pathway. In an embryo, the more stem cells there are, the more NME1 is secreted and it goes from the active dimer to an inactive hexamer (doesn’t bind MUC1*). The paradox was, “How do stem cells limit self-replication, but cancer cells do not?” Answer: A primitive growth factor, NME7AB, looks like a single chain dimer of NME1, so is always active, is expressed in the earliest, naïve stem cells and in metastatic cancer cells. Unpublished Results: Growing cancer cells in recombinant NME7AB for 10 days transforms them into metastatic cells: 1) become non-adherent; 2) enter dormancy; 3) upregulate metastatic markers by 200-fold; 4) form sub-cu tumors in mice from as few as 50 cells; iv injection leads to total metastasis in 10 days; 5) the percent of injected tumor cells that were first grown in NME7AB determines the growth of the entire tumor. We developed a monoclonal antibody that blocks interaction of NME7AB and MUC1*. This antibody reverses established metastasis of breast cancers in animals. NME7AB should be turned off early in embryogenesis, but is aberrantly re-activated in metastatic cancers. Yamanaka factors OCT4, SOX2 and NANOG bind to the promoters of NME7, MUC1 and MMP16, an enzyme that cleaves MUC1 to MUC1* and exposes the cryptic binding site for NME7AB. Conclusions: Primitive growth factor, NME7AB, drives metastasis of solid tumor cancers. Antibody that disrupts NME7AB-MUC1* interaction reverses metastasis in animals. Citation Format: Cynthia C. Bamdad, Benoit J. Smagghe, Mark G. Carter, Trevor J. Grant, Laura M. Reale, Michael J. Nash, Danica M. Walkley, Jac-Leen S. Nash, Kevin R. Yi, Andrew K. Stewart. Metastasis: Cancer cells that have turned on a Yamanaka-like pluripotency program [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2487.

Meddling with Metal Sensors: Fur-Family Proteins as Signaling Hubs.

The ferric uptake regulator (Fur) protein is the founding member of the FUR superfamily of metalloregulatory proteins that control metal homeostasis in bacteria. FUR proteins regulate metal homeostasis in response to the binding of iron (Fur), zinc (Zur), manganese (Mur), or nickel (Nur). FUR family proteins are generally dimers in solution, but the DNA-bound complex can involve a single dimer, a dimer-of-dimers, or an extended array of bound protein. Elevated FUR levels due to changes in cell physiology increase DNA occupancy and may also kinetically facilitate protein dissociation. Interactions between FUR proteins and other regulators are commonplace, often including cooperative and competitive DNA-binding interactions within the regulatory region. Further, there are many emerging examples of allosteric regulators that interact directly with FUR family proteins. Here, we focus on newly uncovered examples of allosteric regulation by diverse Fur antagonists (Escherichia coli YdiV/SlyD, Salmonella enterica EIIANtr, Vibrio parahaemolyticus FcrX, Acinetobacter baumannii BlsA, Bacillus subtilis YlaN, and Pseudomonas aeruginosa PacT) as well as one Zur antagonist (Mycobacterium bovis CmtR). Small molecules and metal complexes may also serve as regulatory ligands, with examples including heme binding to Bradyrhizobium japonicum Irr and 2-oxoglutarate binding to Anabaena FurA. How these protein-protein and protein-ligand interactions act in conjunction with regulatory metal ions to facilitate signal integration is an active area of investigation.

Contribution of Subradiant Plasmon Resonance to Electromagnetic Enhancement in Resonant Raman with Fluorescence Examined by Single Silver Nanoparticle Dimers

The spectral relationships between surface enhanced resonant Raman scattering (SERRS) and plasmon resonance observed in far field scattering cross are investigated using single silver nanoparticle dimers with focusing on the lowest energy (superradiant) plasmon resonance. We find that these relationships can be classified into two types. The first is SERRS spectral envelopes with spectral shapes similar to those of plasmon resonance spectra. The second is SERRS envelopes exhibiting higher energy shifts from the plasmon resonance spectra. These results are examined as an effect of degree of morphological asymmetry in dimers based on an electromagnetic (EM) mechanism. The analysis of the first and second types reveals that dipole-dipole and dipole-quadrupole coupled plasmon resonance (subradiant Fano resonance) respectively determine the EM enhancement. This mechanism is commonly important for the development of plasmonic nanostructures for various surface enhanced spectroscopies.

Exploring the dimer-dimer association of the ebolavirus matrix protein VP40 at the human plasma membrane.

Ebolavirus (EBOV) infections cause the deadly Ebola Virus Disease (EVD) which has a high fatality rate in both human and non-human primates. The EBOV genome codes for only seven proteins that can change structures and have multiple functions during the viral assembly. The matrix protein VP40 is the primary component that makes up the cylindrical structure of the Ebola virus. In addition to its other functions during the viral life cycle, it forms the virion's viral matrix layer below the lipid envelope. Once the VP40 dimers are trafficked to the plasma membrane (PM), they assemble into linear filaments which further associate to form the viral matrix. The end-to-end association of the dimers via their C-terminal interfaces is a crucial step during the formation of the matrix filaments. A crystal structure of the CTD-CTD assembly is available and it provides insight into the nature of the interfacial interactions. In this study, we investigated the lipid interactions of the dimer-dimer filament at the inner leaflet of the PM. We used all-atom molecular dynamics simulations of the dimer-dimer structure of the VP40 associated with the PM and identified the major amino acid residues involved in the lipid interactions. We also compared the differences in the lipid contacts of VP40 of a single dimer versus the lipid contacts with the dimer-dimer conformation.

Accurate Prediction of Electric Fields of Nanoparticles With Deep Learning Methods

Three different deep learning models were designed in this paper, to predict the electric fields of single nanoparticles, dimers, and nanoparticle arrays. For single nanoparticles, the prediction error was 4.4%. For dimers with strong couplings, a sample self-normalization method was proposed, and the error was reduced by an order of magnitude compared with traditional methods. For nanoparticle arrays, the error was reduced from 28.8% to 5.6% compared with previous work. Numerical tests proved the validity of the proposed deep learning models, which have potential applications in the design of nanostructures.