Neighboring Layers Research Articles

Giant Effects of Interlayer Interaction on Valence-Band Splitting in Transition Metal Dichalcogenides

Understanding the origin of valence band maxima (VBM) splitting in transition metal dichalcogenides (TMDs) is important because it governs the unique spin and valley physics in monolayer and multilayer TMDs. In this work, we present our systematic study of VBM splitting ($\Delta$) in atomically thin MoS$_2$ and WS$_2$ by employing photocurrent spectroscopy as we change the temperature and the layer numbers. We found that VBM splitting in monolayer MoS$_2$ and WS$_2$ depends strongly on temperature, which contradicts the theory that spin-orbit coupling solely determines the VBM splitting in monolayer TMDs. We also found that the rate of change of VBM splitting with respect to temperature ($m=\frac{\partial\Delta}{\partial T}$) is the highest for monolayer (-0.14 meV/K for MoS$_2$) and the rate decreases as the layer number increases ($m ~ 0$ meV/K for 5 layers MoS$_2$). We performed density functional theory (DFT) and the GW with Bethe-Salpeter Equation (GW-BSE) calculations to determine the electronic band structure and optical absorption for a bilayer MoS$_2$ with different interlayer separations. Our simulations agree with the experimental observations and demonstrate that the temperature dependence of VBM splitting in atomically thin monolayer and multilayer TMDs originates from the changes in the interlayer coupling strength between the neighboring layers. By studying two different types of TMDs and many different layer thicknesses, we also demonstrate that VBM splitting also depends on the layer numbers and type of transition metals. Our study will help understand the role spin-orbit coupling and interlayer interaction play in determining the VBM splitting in quantum materials and develop next-generation devices based on spin-orbit interactions.

Sediment sorting and bedding dynamics of tidal flat wetlands: Modeling the signature of storms

Field studies suggest that storms can considerably affect the morphology, sedimentology and bedding structure of tidal flat wetlands because of their high-energy, while numerical modeling studies unravelling the underlying mechanisms remain rare. With a tidal flat of the Changjiang Delta, China as a reference site, this study explores the role of storms on sediment sorting and bedding behaviors using a biomorphodynamic model that couples hydrodynamics, sediment transport, marsh dynamics and morphological change. Model results indicate that storms can leave clear signatures on tidal flats in both horizontal and vertical sedimentary features, in agreement with field observations. The high bed shear stress induced by storms can initiate the motion of relatively coarse sediment which can be brought shoreward during the flood and settle on the upper tidal flats (or saltmarshes), altering the typically observed cross-shore “landward fining” phenomenon. The storm-entrained coarse sediment on the higher flat is usually hard to be brought offshore during calm weather, and hence leaving an evident sand-dominated layer (SDL) within neighboring mud-dominated layers (MDL). Storms can also destroy tidal rhythmites formed under calm weather. With the increase in storm intensity and duration, the thickness and the sand fraction of the SDL increase accordingly. The SDL thickness generated by a weaker storm during the spring tide is larger than that of a stronger storm during the neap tide. Storm chronology also plays an important role. In particular, the impact of two overlapping or temporally close storms is larger than the sum of the two individual storms. Overall, this study results in a more in-depth mechanistic understanding of storm impacts on tidal flat biomorphodynamics, providing a scientific facet to make sustainable management strategies for coastal wetlands.

In preprints: buckling under pressure during gastrulation.

In preprints: buckling under pressure during gastrulation.

Recent review on electron transport layers in perovskite solar cells

Organic-inorganic perovskite solar cells demonstrate immense potential for future photovoltaic application due to their remarkable efficiency advancements competitively low-cost. To unlock the full capability of perovskite, developments to the neighbouring layers play immense roles in the ultimate performance of a perovskite solar device. Here, a brief review comprising of the advancements and roles of electron transport layers (ETLs) is discussed. In addition, the effects of ETL on the charge transport, hysteresis, and stability of perovskite solar devices, along with high−performing examples, are also explored.

Asymmetrical magnetic domain wall motion in symmetrical heavy metal/ferromagnet multilayers

In a heavy metal (HM)/ferromagnet (FM)/HM multilayer with a symmetrical sandwich structure, the absence of an interfacial Dzyaloshinskii-Moriya interaction (iDMI) is generally expected. A zero iDMI constant is usually verified by the motion of a magnetic domain wall (DW) with a velocity that is symmetrical to the longitudinal magnetic field (symmetrical DW motion). However, asymmetrical DW motion was still experimentally observed in a symmetrical HM/FM/HM multilayer, and its mechanism is unclear. In this letter, we theoretically prove that even in a perfectly symmetrical HM/FM/HM multilayer with a zero total iDMI constant, asymmetrical DW motion is still possible owing to the exchange coupling between the neighboring FM atomic layers in the FM medium. This work paves a way to unraveling unique DW motion in HM/FM multilayers from a deep perspective of the subtle magnetic interactions within a FM medium.

Investigations in the tape-to-tape contact resistance and contact composition in superconducting CORC® wires

Conductor on Round Core (CORC®) wires and cables, constructed from multiple layers of helically wound REBa2Cu3O7−δ tapes, are a promising cable technology for high field magnet applications. An important feature of high-temperature superconductor cables is the ability to share current between conductors, allowing current to bypass drops in I c and minimizing the risk of hot spot formation, which could lead to potential burnout in the superconductor. In contrast to stacked-tape cables, which have continuous contact between tapes, in CORC® the transfer points occur at discrete tape crossovers. The tape-to-tape contact resistance, R c, plays a critical role in the current sharing capabilities and current distribution in cables. For the work reported here, special CORC® wires were manufactured using different winding parameters to investigate variations in R c. Variations comprised inclusion of a lubricant, different lubricant conductivity, inclusion of pre-tinning, and heating briefly to melt the solder. Cables were first tested as straight lengths, followed by bending to a 10 cm diameter. In straight cables R c values ranged from 1 to over 1000 μΩ cm2, depending on cabling parameters, with the highest values being found for cables made by the present ‘standard’ process. Bending the cables to a 10 cm diameter decreased R c by a factor 2–5. Tinning with PbSn decreased R c by three orders of magnitude compared to standard CORC® wires, and heat treating wires with tinned conductor resulted in only a small further decrease in R c. Based on the measured R c at an electric field of 1 μV cm−1 the resulting current transfer length between layers can range from a few millimeters to a tens of centimeters. Examination of contacts with a laser confocal microscope showed plastic deformation of the copper at the edges of the contact overlap area, apparently caused by thicker plating at tape edges digging into the copper of neighboring layers. These images reveal that only a fraction of the total contact surface may actually be touching when there is nothing to compensate for height differential. Images of the PbSn coated tapes indicated that application of solder produces a much more uniform contact surface and higher contact area. Furthermore, imaging of CORC® cross-sections confirmed that in the non-tinned cables there are many regions where tapes are not in contact, while in contrast the PbSn cable shows significantly more contact between the tapes. These different imaging techniques reveal that tape surface morphology is a significant parameter in determining R c.

Atomic Intercalation Induced Spin-Flip Transition in Bilayer CrI3.

The recent discovery of 2D magnets has induced various intriguing phenomena due to the modulated spin polarization by other degrees of freedoms such as phonons, interlayer stacking, and doping. The mechanism of the modulated spin-polarization, however, is not clear. In this work, we demonstrate theoretically and computationally that interlayer magnetic coupling of the CrI3 bilayer can be well controlled by intercalation and carrier doping. Interlayer atomic intercalation and carrier doping have been proven to induce an antiferromagnetic (AFM) to ferromagnetic (FM) phase transition in the spin-polarization of the CrI3 bilayer. Our results revealed that the AFM to FM transition induced by atom intercalation was a result of enhanced superexchange interaction between Cr atoms of neighboring layers. FM coupling induced by O intercalation mainly originates from the improved superexchange interaction mediated by Cr 3d-O 2p coupling. FM coupling induced by Li intercalation was found to be much stronger than that by O intercalation, which was attributed to the much stronger superexchange by electron doping than by hole doping. This comprehensive spin exchange mechanism was further confirmed by our results of the carrier doping effect on the interlayer magnetic coupling. Our work provides a deep understanding of the underlying spin exchange mechanism in 2D magnetic materials.

A series of coordination polymers constructed by 2-phenylsuccinic acid and flexible bis(imidazole) ligands: Syntheses, structures, and photoluminescent properties

Eight coordination polymers (CPs), namely, [Co(μ-phsuc)(μ-obix)]n(1), {[Co2(μ-phsuc)2(μ-pbix)1.5]⋅2H2O}n(2), [Zn(μ-phsuc)(μ-obix)]n(3), {[Zn(μ-phsuc)(μ-mbix)]⋅H2O}n(4), {[Zn(μ-phsuc)(μ-pbix)]⋅H2O}n(5), {[Zn(μ-phsuc)(μ-pbix)]⋅1.5H2O⋅CH3OH}n(6), [Cd(μ-phsuc)(μ-obix)]n(7) and [Cd(μ3-phsuc)(μ-pbix)0.5]n(8) (phsucH2 = 2-phenylsuccinic acid, obix = 1,2-bis((imidazol-1-yl)methyl)benzene, mbix = 1,3-bis((imidazol-1-yl)methyl)benzene, pbix = 1,4-bis((imidazol-1-yl)methyl)benzene), were solvothermally synthesized and characterized by IR spectroscopy, elemental analysis, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), and thermal analyses. The structural analyses revealed that the compounds were 2D coordination polymers, in which metal ions were in tetrahedral coordination geometries in 1-6 and in octahedral coordination geometries in 2, 7 and 8. Compounds 1, 3, 4, 5, 7 and 8 displayed 4-connected 2D wave sheets with the point symbol of {44.62}. Compound 2 was rare example exhibiting a 2D polyrotaxane structure. Compound 6 showed a two-fold interpenetrated 2D structure with hcb topology (the point symbol of {63}). In the compounds, the neighboring 2D layers were further assembled by π⋅⋅⋅π stacking and weak C–H⋅⋅⋅π interactions into the 3D supramolecular framework. The effects of the bis(imidazole) linkers and metals ions on the framework assemblies have been discussed. In addition, thermal and photoluminescent and optical properties of the compounds were investigated.

Elucidating structure and dynamics of crystalline α-zirconium phosphates intercalated with water and methanol by multinuclear solid-state MAS NMR: A comprehensive NMR approach.

Solid-state NMR experiments on 2 H, 31 P, 13 C, and 1 H nuclei, including 31 P T1 , 1 H T1 , and 1 H T1ρ measurements, as well as on the kinetics of proton-phosphorus cross-polarization have been performed to characterize the crystalline and amorphous α-zirconium phosphates, which were intercalated with D2 O and/or CD3 OD. The 13 C{1 H} CP MAS NMR experiment performed for compound 1-CD3 OD (Zr (HPO4 )2. 0.2CD3 OD) with carbon cross-polarization via protons of phosphate groups has provided a prove that the methanol was intercalated into the interlayer spaces of this compound. The variable-temperature 2 H solid-echo MAS NMR spectra of intercalated compounds demonstrated that the methanol molecules, in contrast to the mobile water, were immobile, keeping, however, free CD3 rotations around the C3 -axis. It has been demonstrated that the intercalated species, D2 O and CD3 OD, do not affect the high-frequency motions of the phosphate groups. By utilizing local structural models that satisfy the constraints of the experimental data, it has been suggested that the immobile methanol molecules are located in the cavity between two neighboring layers of the zirconium phosphates. Thus, the present work illustrates the reliable criteria in a comprehensive NMR approach to structural and dynamic studies of such systems.

Optoelectrical analysis of TCO+Silicon oxide double layers at the front and rear side of silicon heterojunction solar cells

Silicon Heterojunction has become a promising technology to substitute passivated emitter and rear contact (PERC) solar cells in pursuance of lower levelized cost of electricity through high efficiency devices. While high open circuit voltages and fill factors are reached, current loss related to the front and rear contacts, such as the transparent conductive oxide (TCO) layers is still a limiting factor to come closer to the efficiency limit of silicon based solar cells. Furthermore, reducing indium consumption for the TCO has become mandatory to push silicon heterojunction technology towards a terawatt scale production due to material scarcity and costs. To address these issues dielectric layers, such as silicon dioxide or nitride cappings are implemented to reduce TCO thicknesses both diminishing parasitic absorption and material consumption. However, reducing the TCO thickness comes in cost of resistive losses. Furthermore, the TCO properties do vary with thickness and neighboring layer configuration altering the optimization frame of the device. In this paper we present a detailed analysis to quantify the optoelectrical losses trade-off associated to the TCO thickness reduction in such layer stacks. Through the analysis we show and explain why experimental bifacial cells with 20 nm front and rear TCO perform at a similar level to reference cells with 75 nm under front and rear illumination reaching efficiency close to 24% at 92% bifaciality. We present as well a simple interconnection method via screen printing metallization to implement a thin TCO/silicon dioxide/silver reflector enhancing current density from 39.6 to 40.4 mA/cm 2 without compromising resistive losses resulting in a 0.2% absolute solar cell efficiency increase from a bifacial design (23.5–23.7%). Finally, following this approach we present a certified champion cell with an efficiency of 24.6%. • Analysis of TCO variations on electron and hole contact for Si heterojunction solar cells by simulations and experiments. • Both sides 20 nm TCO + SiO 2 layer stack SHJ solar cells with 23.9% efficiency. • Champion solar cell with rear 20 nm TCO + SiO 2 layer stack and silver rear reflector with 24.6% efficiency.

Microstructures and mechanical properties of functionally graded TiCN–TaC ceramics prepared by a novel layer processing strategy

Functionally graded TiCN–TaC ceramics (FGTTCs) were fabricated using a novel layer processing method based on a vacuum hot-press sintering technology. Microstructural investigations revealed a visibly layered structure for the FGTTCs with relatively flat boundaries between the neighboring layers; additionally, the layer thickness was facilely controlled. With an increase in the sintering temperature, the hardness and flexural strength of the surface and middle layers of the FGTTCs initially increased, and then decreased. The fracture toughness of the surface layer did not undergo significant changes after sintering at various temperatures, except at 1500 °C. The FGTTC sintered at 1350 °C contained uniform fine grains and simultaneously exhibited transgranular and intergranular fracture modes. Further, it presented excellent comprehensive mechanical properties, i.e., surface layer hardness = 20.28 ± 0.18 GPa, flexural strength = 1553.76 ± 22 MPa, surface layer fracture toughness = 7.29 ± 0.24 MPa m1/2. Under the same sintering conditions, our FGTTCs presented superior mechanical properties against homogeneous TiCN–TaC ceramics (HTTCs), achieving a considerably higher flexural strength (1553.76 ± 22 vs 953.35 ± 24 MPa).

Role of layer thickness and dislocation distribution in confined layer slip in nanolaminated Nb

Confined layer slip (CLS) is considered as the primary mechanism for plastic deformation in nanolaminates. It depicts the confined motion of a single dislocation between two parallel interfaces nanometers apart. Using atomistic simulations, we investigate the effects of interface spacing, or equivalently individual layer thickness, and dislocation distribution on the CLS of an edge dislocation in nanolaminated Nb with coherent twin boundaries and Nb nanofilm. We show that CLS motion transitions from smooth glide to staggered glide as the nanolayer thickness increases, while the line bows out, as theoretically pictured. For the same nanolayer thicknesses L, dislocation CLS in the nanofilm is smooth and the CLS resistance is 47% to 79% lower. For both the nanolaminate and film, the nanolayer size L effect on CLS resistance is found to follow the expected ln(L)/L scaling with an additional constant that depends on the interface/dislocation interaction but is independent of L. When like-signed dislocation glide concurrently on the same glide plane in the adjacent layers, the dislocations move with almost no bow-out, and the CLS resistance is substantially reduced, even below that of the thin film bounded by two free surfaces. With an increase in the glide plane separation between like-signed dislocations in the neighboring layers, a higher flow stress is obtained. However, when the dislocations are oppositely signed, CLS motion is jerky and the stress fluctuates and overall increases three fold.

Band structure of free Sb layers and spin-orbit splitting of surface bands

As follows from performed DFT calculations, a semimetal state of the bulk Sb crystal results from a spontaneous coupling of neighboring layers. The related decrease of DOS in vicinity of Fermi level, in turn, may be considered as the driving force of the coupling and formation of the characteristic bilayer structure of Sb crystal. The same mechanism of structural transformations is pertinent also to Sb films, built from several hexagonal monolayers. In particular, the coupling leads to semimetallic properties of films built from even number of Sb(111) monolayers, while the films with an odd number of monolayers are strongly metallic, with a high density of states at Fermi level. This feature can be used to control the surface electronic structure by deposition of the proper number of Sb monolayers onto appropriate substrate. Hydrogen monolayer on one face of the Sb(111) film leads to the spin-orbit splitting of the bands.

Constructing proton exchange membranes with high and stable proton conductivity at subzero temperature through vacuum assisted flocculation technique

The application of proton exchange membranes in low temperature proton exchange membrane fuel cells requires the quick and stable proton conduction at subzero temperature. In this research, we constructed the multilayered membranes through the alternate deposition of poly(vinyl alcohol) (PVA), Kevlar nanofibers and carbon nanotube oxides (OCNTs) through the vacuum assisted flocculation (VAF) technique. The intermolecular hydrogen bonds resulted in the preparation of (PVA/Kevlar/OCNTs)3 membranes with layered structure. Phosphoric acid (PA) molecules entered the gaps between the neighboring layers accompanying with the phase separation. The prepared membranes exhibited the high and stable proton conductivity at subzero temperature, such as 2.04 × 10-2 S/cm at −30 °C and 1.52 × 10-1 S/cm at 30 °C. The proton conductivity gradually changed to 5.52 × 10-2 S/cm and 1.84 × 10-1 S/cm even after the ten-cycles process of −30 °C–30 °C. In addition, the value can retain 1.42 × 10-2 S/cm at −30 °C in a 1900 h non-stop test. The evaporation and liquefaction of water molecules could affect proton conductivity besides PA dominating the proton conduction behavior during heating/cooling processes. Furthermore, the balance on low temperature proton conduction and mechanical strength makes the multilayered (PVA/Kevlar/OCNTs)3/PA membranes as a promising PEM candidate at subzero temperature.

The influence of orbital moments in anomalous Hall effect in Co/Ni multilayers with perpendicular magnetic anisotropy

We focus on the anomalous Hall effects (AHEs) of Co/Ni multilayers with perpendicular magnetic anisotropy (PMA) by using Ta, Nb, and Cu as the buffer and top layer. An un-conventional AHE behavior was found in which the AH resistance exhibits two anti-symmetric peaks in the presence of a magnetic field. Moreover, Co/Ni multilayers with a Ta neighboring layer show reverse AH resistance compared to the Nb and Cu neighboring layers, except Ta bottom and Cu capping layers. The former can be explained by considering the influence of the external magnetic field on the interfacial spin orbit interaction due to spontaneous symmetry breaking at the ferromagnetic (FM)/FM layer interface. Furthermore, the reverse Co/Ni AHE with a Ta adjacent layer can be interpreted as the leakage spin current of proximity effects from Ta due to its larger spin–orbit coupling, and finally, taking the shunting action of the Cu layer into account, the Co/Ni AHE with Ta and Cu adjacent layers can also be explained. Our results provide a clear physics picture of the AHE in a two-dimensional nano-scaling FM/FM interface with PMA; in particular, this work shows that the non-magnetic adjacent layer with large spin–orbit coupling will play an important role in the understanding of AHE in two-dimensional FM multilayers.

Clearing-based multimodal multi-objective evolutionary optimization with layer-to-layer strategy

Equivalent Pareto sets and local Pareto sets in decision space are involved in multimodal multi-objective optimization problems (MMOPs). While popular multimodal multi-objective evolutionary algorithms (MMEAs) devote greater attention to locating equivalent Pareto sets in decision space, resulting in the fact that local Pareto sets are overlooked. To tackle this issue, a clearing-based evolutionary algorithm with layer-to-layer evolution strategy (CEA-LES) is therefore proposed in this paper. A clearing-based niching technique is used in CEA-LES to remove inferior local Pareto optimal solutions, in which the clearing radius dynamically changes with the number of nearest neighbors of each individual. To develop equivalent global Pareto sets and local Pareto sets, a layer-to-layer evolutionary strategy is proposed based on Pareto ranking. Each layer performs mutation selection and reproduction operations with the aid of its closest neighbor layer to produce offspring. Particularly, the whole evolutionary operation is divided into two stages, and the first stage is to select parents using the roulette method and the second stage is using the tournament method. An environmental selection strategy is suggested to maintain diverse solutions and balance the distribution of solutions. The proposed algorithm is performed on CEC 2020 MMOPs benchmark with local Pareto set and Polygon-based MMOPs and is compared with some state-of-the-art MMEAs. Experimental results demonstrate that the proposed algorithm obtains superior performance in comparison to its competing algorithms, and is capable of locating equivalent global Pareto sets and local Pareto sets, simultaneously.

Observation of Spin‐Induced Ferroelectricity in a Layered van der Waals Antiferromagnet CuCrP2S6

AbstractCuCrP2S6, a van der Waals magnet having stacked layers of 2D honeycomb lattice made of CuS3 triangles and CrS6 octahedra, exhibits an A‐type antiferromagnetic order with the Néel temperature (TN) = 32 K. Upon in‐plane magnetic field (H) being applied below TN, H‐induced modulation of the c*‐axis electric polarization (ΔPc*) is found at fields lower than the saturation field µ0HS = 6.1 T, at which a forced ferromagnetic alignment sets in. Based on the symmetry analyses and dependence of ΔPc* on H and the azimuthal angle of applied H direction, a microscopic origin of the magnetoelectric (ME) coupling is attributed to the spin‐direction‐dependent p–d hybridization that is allowed due to the presence of off‐centered Cr3+ octahedra. A comparative study on CuCrP2Se6, however, finds no H‐induced P modulation due to cancellation of P between neighboring layers with the doubling of a crystallographic unit cell at TN. As the p–d hybridization mechanism allows generation of P in a single Cr atom–ligand pair, the results imply that large ME coupling should exist even in a single layer limit of CuCrP2S6.

Comparative Study on the Uniform Energy Deposition Achievable via Optimized Plasmonic Nanoresonator Distributions

Plasmonic nanoresonators of core–shell composition and nanorod shape were optimized to tune their absorption cross-section maximum to the central wavelength of a short laser pulse. The number density distribution of randomly located nanoresonators along a laser pulse-length scaled target was numerically optimized to maximize the absorptance with the criterion of minimal absorption difference between neighboring layers illuminated by two counter-propagating laser pulses. Wide Gaussian number density distribution of core–shell nanoparticles and nanorods enabled to improve the absorptance with low standard deviation; however, the energy deposited until the overlap of the two laser pulses exhibited a considerable standard deviation. Successive adjustment resulted in narrower Gaussian number density distributions that made it possible to ensure almost uniform distribution of the deposited energy integrated until the maximal overlap of the two laser pulses. While for core–shell nanoparticles the standard deviation of absorptance could be preserved, for the nanorods it was compromised. Considering the larger and polarization independent absorption cross-section as well as the simultaneously achievable smaller standard deviation of absorptance and deposited energy distribution, the core–shell nanoparticles outperform the nanorods both in optimized and adjusted nanoresonator distributions. Exception is the standard deviation of deposited energy distribution considered for the complete layers that is smaller in the adjusted nanorod distribution. Optimization of both nanoresonator distributions has potential applications, where efficient and uniform energy deposition is crucial, including biomedical applications, phase transitions, and even fusion.

Magnetic properties of the layered heavy-fermion antiferromagnet CePdGa6

We report the magnetic properties of the layered heavy fermion antiferromagnet CePdGa$_{6}$, and their evolution upon tuning with the application of magnetic field and pressure. CePdGa$_{6}$ orders antiferromagnetically below $T\rm_{N}$ = 5.2 K, where there is evidence for heavy fermion behavior from an enhanced Sommerfeld coefficient. Our results are best explained by a magnetic ground state of ferromagnetically coupled layers of Ce $4f$-moments orientated along the $c$-axis, with antiferromagnetic coupling between layers. At low temperatures we observe two metamagnetic transitions for fields applied along the $c$-axis corresponding to spin-flip transitions, where the lower transition is to a different magnetic phase with a magnetization one-third of the saturated value. From our analysis of the magnetic susceptibility, we propose a CEF level scheme which accounts for the Ising anisotropy at low temperatures, and we find that the evolution of the magnetic ground state can be explained considering both antiferromagnetic exchange between nearest neighbor and next nearest neighbor layers, indicating the influence of long-range interactions. Meanwhile we find little change of $T\rm_{N}$ upon applying hydrostatic pressures up to 2.2 GPa, suggesting that significantly higher pressures are required to examine for possible quantum critical behaviors.

The crystal structure of mineral magadiite, Na2Si14O28(OH)2∙8H2O

Abstract Magadiite from Lake Magadi was structurally analyzed based on X-ray powder diffraction data. The idealized chemical composition of magadiite is Na16[Si112O224(OH)16]∙64H2O per unit cell. The XRD powder diffraction pattern was indexed in orthorhombic symmetry with lattice parameters a0 = 10.5035(9) Å, b0 = 10.0262(9) Å, and c0 = 61.9608(46) Å. The crystal structure was solved from a synthetic magadiite sample in a complex process using 3D electron diffraction combined with model building as presented in an additional paper. A Rietveld refinement of this structure model performed on a magadiite mineral sample in space group F2dd (No. 43) converged to residual values of RBragg = 0.031 and RF = 0.026 confirming the structure model. Physico-chemical characterization using solid-state NMR spectroscopy, SEM, TG-DTA, and DRIFT spectroscopy further confirmed the structure. The structure of magadiite contains two enantiomorphic silicate layers of, so far, unknown topology. The dense layers exhibit no porosity or micro-channels and have a thickness of 11.5 Å (disregarding the van der Waals radii of the terminal O atoms) and possess a silicon Q4 to Q3 ratio of 2.5. 16 out of 32 terminal silanol groups are protonated, and the remaining groups compensate for the charge of the hydrated sodium cations. Bands of edge-sharing [Na(H2O)6/1.5] octahedra are intercalated between the silicate layers extending along (110) and (110). The water molecules are hydrogen bonded to terminal silanol groups with O···O distances of 2.54–2.91 Å. The structure of magadiite is slightly disordered, typical for hydrous layer silicates (HLS), which possess only weak interactions between neighboring layers. In this respect, the result of the structure refinement represents a somewhat idealized structure. Nevertheless, the natural magadiite possesses a higher degree of structural order than any synthetic magadiite sample. The structure analysis also revealed the presence of strong intra-layer hydrogen bonds between the terminal O atoms (silanol/siloxy groups), confirmed by 1H MAS NMR and DRIFT spectroscopy. The surface zone of the silicate layers, as well as the interlayer region containing the [Na(H2O)6/1.5] octahedra, are closely related to the structure of Na-RUB-18.