Water-in-oil microemulsion method preparation and capacitance performance study of Li4Mn5O12

Spinel Li₄Mn₅O₁₂ nanoparticles are successfully prepared by water-in-oil microemulsion method and characterized by X-ray diffraction and scanning electron microscopy. The Li₄Mn₅O₁₂ nanoparticles have sphere-like morphology with particle size less than 50 nm. The Li₄Mn₅O₁₂ and activated carbon (AC) were used as electrodes of Li₄Mn₅O₁₂/AC supercapacitor, respectively. The electrochemical capacitance performance of the supercapacitor was investigated by cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy. The results showed that the single electrode was able to deliver specific capacitance 252 F g^?1 within potential range 0–1.4 V at a scan rate of 5 mV s^?1 in 1 mol L^?1 Li₂SO₄ solution, and it also showed high coulombic efficiency close to 100%. This material exhibited a good cycling performance.     

A new tavorite LiTiPO<Subscript>4</Subscript>F electrode material for aqueous rechargeable lithium ion battery

Herein, we demonstrate a safe, inexpensive, and stable cycle-life aqueous rechargeable Li-ion battery system using tavorite LiTiPO₄F as anode and Li[Li_0.2Co_0.3Mn_0.5]O₂ as cathode in aqueous electrolyte using 2 M Li₂SO₄. These materials have been synthesized via a simple and an efficient method called RAPET (reaction under autogenic pressure at elevated temperature) method, and for the first time, we have evaluated the electrochemical properties of LiTiPO₄F in aqueous electrolyte. Structural and morphological features have been characterized using X-ray diffraction and scanning electron microscopy techniques, and the electrochemical studies have been investigated by using cyclic voltammetry, galvanostatic charge/discharge studies, electrochemical impedance spectroscopic technique, potentiostatic intermittent titration techniques, and galvanostatic intermittent titration techniques. In galvanostatic charge/discharge studies, the capacity, cycle life, and columbic efficiency of LiTiPO₄F have been tested in combination with Li [Li_0.2Co_0.3Mn_0.5]O₂ cathode. In particular, LiTiPO₄F shows capacity of 82 mA h g^?1, the capacity retention was maintained 90 % even after the 45th cycle.     

Sn-doped Li<Subscript>1.2</Subscript>Mn<Subscript>0.54</Subscript>Ni<Subscript>0.13</Subscript>Co<Subscript>0.13</Subscript>O<Subscript>2</Subscript> cathode materials for lithium-ion batteries with enhanced electrochemical performance

Sn-doped Li-rich layered oxides of Li_1.2Mn_0.54-x Ni_0.13Co_0.13Sn _x O₂ have been synthesized via a sol-gel method, and their microstructure and electrochemical performance have been studied. The addition of Sn⁴⁺ ions has no distinct influence on the crystal structure of the materials. After doped with an appropriate amount of Sn⁴⁺, the electrochemical performance of Li_1.2Mn_0.54-x Ni_0.13Co_0.13Sn _x O₂ cathode materials is significantly enhanced. The optimal electrochemical performance is obtained at x = 0.01. The Li_1.2Mn_0.53Ni_0.13Co_0.13Sn_0.01O₂ electrode delivers a high initial discharge capacity of 268.9 mAh g^?1 with an initial coulombic efficiency of 76.5% and a reversible capacity of 199.8 mAh g^?1 at 0.1 C with capacity retention of 75.2% after 100 cycles. In addition, the Li_1.2Mn_0.53Ni_0.13Co_0.13Sn_0.01O₂ electrode exhibits the superior rate capability with discharge capacities of 239.8, 198.6, 164.4, 133.4, and 88.8 mAh g^?1 at 0.2, 0.5, 1, 2, and 5 C, respectively, which are much higher than those of Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ (196.2, 153.5, 117.5, 92.7, and 43.8 mAh g^?1 at 0.2, 0.5, 1, 2, and 5 C, respectively). The substitution of Sn⁴⁺ for Mn⁴⁺ enlarges the Li⁺ diffusion channels due to its larger ionic radius compared to Mn⁴⁺ and enhances the structural stability of Li-rich oxides, leading to the improved electrochemical performance in the Sn-doped Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ cathode materials.     

Synthesis of single-crystal magnesium-doped spinel lithium manganate and its applications for lithium-ion batteries

Single-crystal magnesium-doped spinel lithium manganate cathode materials are prepared by the hydrothermal method followed by the heat treatment. XRD patterns reveal that Mg²⁺ions have already diffused into the Li_1.088Mn_1.912O₄ crystal structure and not affect the Fd3m space group. SEM images demonstrate that the magnesium-doped spinel lithium manganates show uniform polyhedral single crystals with 2–4 μm. Electrochemical performance demonstrates that the optimized composition of Li_1.088Mg_0.070Mn_1.842O₄ electrode exhibits the best electrochemical properties. It delivers 92.0 mAh g^?1 at 8C rates and corresponds to 90.8% capacity retention (vs. 1C), far higher than those of the pristine electrode (70.4 mAh g^?1 and 69.2%). In addition, the Li_1.088Mg_0.070Mn_1.842O₄ electrode also shows 95.5% capacity retention after 100 cycles at 1C, while the pristine electrode only shows 91.0% capacity retention. The excellent electrochemical performances of Li_1.088Mg_0.070Mn_1.842O₄ electrode are ascribed to the suppressed polarization, more stable crystal structure, and better kinetic characteristics.     

Preparation and electrochemical performance of nano-structured Li<Subscript>2</Subscript>Mn<Subscript>4</Subscript>O<Subscript>9</Subscript> for supercapacitor

Nano-structured spinel Li₂Mn₄O₉ powder was prepared via a combustion method with hydrated lithium acetate (LiAc·2H₂O), manganese acetate (MnAc₂·4H₂O), and oxalic acid (C₂H₂O₄·2H₂O) as raw materials, followed by calcination of the precursor at 300 °C. The sample was characterized by X-ray diffraction, scanning electron microscope, and energy-dispersive X-ray spectroscopy techniques. Electrochemical performance of the nano-Li₂Mn₄O₉ material was studied using cyclic voltammetry, ac impedance, and galvanostatic charge/discharge methods in 2 mol L⁻¹ LiNO₃ aqueous electrolyte. The results indicated that the nano-Li₂Mn₄O₉ material exhibited excellent electrochemical performance in terms of specific capacity, cycle life, and charge/discharge stability, as evidenced by the charge/discharge results. For example, specific capacitance of the single Li₂Mn₄O₉ electrode reached 407 F g⁻¹ at the scan rates of 5 mV s⁻¹. The capacitor, which is composed of activated carbon negative electrode and Li₂Mn₄O₉ positive electrode, also exhibits an excellent cycling performance in potential range of 0–1.6 V and keeps over 98% of the maximum capacitance even after 4,000 cycles.     

Improvement of electrochemical performance for Li-rich spherical Li1.3[Ni0.35Mn0.65]O2+x modified by Al2O3

The Li-rich Li_1.3[Ni_0.35Mn_0.65]O_2+x microspheres are firstly prepared and subsequently transferred into the Al₂O₃-coated Li-rich Li_1.3[Ni_0.35Mn_0.65]O_2+x microspheres by a simple deposition method. The as-prepared samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge/discharge tests. The results reveal that the Al₂O₃-coated Li-rich Li_1.3[Ni_0.35Mn_0.65]O_2+x sample has a typical α-NaFeO₂ layered structure with the existence of Li₂MnO₃-type integrated component, and the Al₂O₃ layer is uniformly coated on the surface of the spherical Li-rich Li_1.3[Ni_0.35Mn_0.65]O_2+x particles with a thickness of about 4 nm. Importantly, the Al₂O₃-coated Li-rich sample exhibits obviously improved electrochemical performance compared with the pristine one, especially the 2 wt.% Al₂O₃-coated sample shows the best electrochemical properties, which delivers an initial discharge capacity of 228 mAh g^?1 at a rate of 0.1 C in the voltage of 2.0–4.6 V, and the first coulombic efficiency is up to 90 %. Furthermore, the 2 wt.% Al₂O₃-coated sample represents excellent cycling stability with capacity retention of 90.9 % at 0.33 C after 100 cycles, much higher than that of the pristine one (62.2 %). Particularly, herein, the typical inferior rate capability of Li-rich layered cathode is apparently improved, and the 2 wt.% Al₂O₃-coated sample also shows a high rate capability, which can deliver a capacity of 101 mAh g^?1 even at 10 C. Besides, the thin Al₂O₃ layer can reduce the charge transfer resistance and stabilize the surface structure of active material during cycling, which is responsible for the improvement of electrochemical performance of the Li-rich Li_1.3[Ni_0.35Mn_0.65]O_2+x .     

Development of a new in situ cell for the X–ray Absorption Fine Structure analysis of the electrochemical reaction in a rechargeable battery and its application to the Lithium Battery Material,Li1+yMn2−yO4

An electrochemical cell was developed for the in situ transmission X–ray Absorption Fine Structure measurements of the charge/discharge process of the cathode materials of lithium secondary batteries, from which Li can be electrochemically deintercalated or intercalated. The dynamical structural behavior of Mn in Li(Mn_1.93Li_0.07)O₄, and Li(Mn_1.85Li_0.15)O₄ as a function of both excess Li content and the Li deintercalation was revealed using the in situ cell. The analysis disclosed the coexistence of two MnO₆–coordination polyhedra with different Mn–O distances for the Mn³⁺ and Mn⁴⁺ ions at the 16d site of the spinel structure. Because the charge–discharge process accompanies the oxidation–reduction of the Mn ions, this size difference causes an unfavorable lattice distortion for the electrode materials which can cause a loss of cell capacity after cyclic use of the cell. A partial substitution of Li for Mn will diminish this effect and will be favorable for the battery material.     

Impedance study on the correlation between phase transition and electrochemical degradation of Si-based materials

In order to explain the relationship between physical change and electrochemical degradation of Co–Co₃O₄ coated Si, impedance spectroscopy on Co–Co₃O₄ coated Si was conducted at various states during charge or discharge. Nyquist plots during Li⁺ insertion (charge) showed a unique behavior that below 70 mV vs. Li/Li⁺, the more Li⁺’s were inserted into the electrode, the larger its comprehensive resistance was getting. During Li⁺ extraction (discharge), electrode resistance was decreased after going through 0.43 V vs Li/Li⁺. When these data were fitted with the ordinary equivalent circuit which is composed of electrolyte resistance, charge transfer resistance and contact resistance, there was an abrupt augmentation of charge transfer resistance below 70 mV vs. Li/Li⁺ during charge, whereas there was its drastic diminishment between 0.2 and 0.5 V vs. Li/Li⁺ during discharge. Because these potential regions are each related to amorphous Li_xSi-to-Li₁₅Si₄ transition and vice versa, it could be shown that the formation and decomposition of Li₁₅Si₄ is responsible for the electrochemical degradation of Co–Co₃O₄ coated Si.     

Vinyl-functionalized imidazolium ionic liquids as new electrolyte additives for high-voltage Li-ion batteries

Four functionalized ionic liquids based on imidazolium cations with vinyl or alllyl group and TFSI^? anion were synthesized as electrolyte additives for high-voltage Li-ion battery to stabilize carbonate-based electrolytes on the surface of 5 V class cathode materials. The electrochemical behaviors and surface morphology of LiNi_0.5Mn_1.5O₄ cathode had been investigated by cyclic voltammetry, charge–discharge test, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM), respectively. Cycle life and rate performance of the Li/LiNi_0.5Mn_1.5O₄ cells containing 1.2 M LiPF₆ in ethylene carbonate/ethyl methyl carbonate can be improved by adding 1-allyl-3-vinyl imidazolium bis(trifluoromethanesulphonyl)imide ([AVIm][TFSI]). The addition of 3 wt.% [AVIm][TFSI] results in high discharge capacity of above 130 mAh g^?1. Surface analysis of the cathode material (XPS and SEM) suggested that a stable and compact polymer film was formed on the LiNi_0.5Mn_1.5O₄ cathode by electroinitiated polymerization of imidazolium cation with vinyl and allyl group.     

Influence of preparation method on structure, morphology, and electrochemical performance of spherical Li[Ni0.5Mn0.3Co0.2]O2

Spherical Li[Ni_0.5Mn_0.3Co_0.2]O₂ was prepared by both the continuous hydroxide co-precipitation method and continuous carbonate co-precipitation method under different calcined temperatures. The physical properties and electrochemical behaviors of Li[Ni_0.5Mn_0.3Co_0.2]O₂ prepared by two methods were characterized by X-ray diffraction, scanning electron microscope, and electrochemical measurements. It has been found that different preparation methods will result in the differences in the morphology (shape, particle size, and tap density), structure stability, and the electrochemical characteristics (shape of initial charge/discharge curve, cycle stability, and rate capability) of the final product Li[Ni_0.5Mn_0.3Co_0.2]O₂. The physical and electrochemical properties of the spherical Li[Ni_0.5Mn_0.3Co_0.2]O₂ prepared by continuous hydroxide co-precipitation is apparently superior to the one prepared by continuous carbonate co-precipitation method. The optimal sample prepared by continuous hydroxide co-precipitation at 820 °C exhibits a hexagonally ordered layer structure, high special discharge capacity, good capacity retention, and excellent rate capability. It delivers high initial discharge capacity of 175.2 mAh g^?1 at 0.2 C rate between 3.0 and 4.3 V, and the capacity retention of 98.8 % can be maintained after 50 cycles. While the voltage range is broadened up to 2.5 and 4.6 V vs. Li⁺/Li, the special discharge capacities at 0.2 C, 0.5 C, 1 C, 2 C, 5 C, and 10 C rates are as high as 214.3, 205.0, 198.3, 183.3, 160.1 and 135.2 mAh g^?1, respectively.     

Improved molten salt synthesis and structure evolution upon cycling of 0.5Li2MnO3·0.5LiCoO2 in lithium-ion batteries

The Li-rich cathode material Li_1.2Co_0.4Mn_0.4O₂(=0.5Li₂MnO₃·0.5LiCoO₂) was prepared by an improved molten salt method. The effects of sintering temperature and time on the physical and electrochemical properties of Li_1.2Co_0.4Mn_0.4O₂ were investigated. With increasing sintering temperature, excellent crystallinity and a stable structure are obtained, which lead to excellent electrochemical properties. However, the sample sintered at 900 °C has poor performance because its large powder diameter prolongs the transportation length of Li⁺ ions. Higher specific surface areas are obtained when samples are sintered at 850 °C for a shorter time, which leads to more activity and excellent charge/discharge capacity. The evolution of a derivative peak at about 3.0 V in the differential capacity (dQ/dV) curves is observed along with the formation of a spinel-like phase, which is verified by analysis using a high-resolution transmission electron microscope. Therefore, it is a simple and quick method to characterize the structure evolution upon cycling of Li-rich cathode materials by means of analysis of the derivative peak.     

Synthesis and characterization of LiNi1/3Co1/3Mn1/3O2 cathode material for rechargeable lithium batteries by polyacrylic acid-assisted sol–gel method

Nanocrystalline LiNi_1/3Co_1/3Mn_1/3O₂ cathode materials are synthesized by sol–gel method using polyacrylic acid as a chelating agent. The effects of the calcination temperature and calcination time on the structure, morphology, and electrochemical performances of the LiNi_1/3Co_1/3Mn_1/3O₂ electrode materials are investigated by X-ray diffraction, scanning electron microscopy and charge–discharge cycling test, respectively. All experiments show that the microscopic structural features and the morphology properties are deeply related with the electrochemical performance. The results show that the nanocrystalline LiNi_1/3Co_1/3Mn_1/3O₂ with a particle size of 80 nm sintered at 700 °C for 2 h presents good α-NaFeO₂ layer structure and the best electrochemical performance. When it is discharged between 4.4 and 2.8 V at 20 mAg^?1, the initial specific capacity of the LiNi_1/3Co_1/3Mn_1/3O₂ obtained at 700 °C for 2 h is 169.2 mAhg^?1. The investigated electrode materials retain 151 mAhg^?1 after 30 cycles when cycled at 20 mAg^?1.     

Li4Ti5O12/(Cu+C)复合材料的制备及电化学性能

以Li₄Ti₅O₁₂,Cu(CH₃COO)₂·H₂O和C₆H₁₂O₆为前驱体,化学沉积与热分解结合合成锂离子电池负极材料Li₄Ti₅O₁₂/(Cu+C)。采用X-射线衍射(XRD)、扫描电子显微镜(SEM)、恒流充放电、循环伏安和电化学阻抗方法表征样品的结构、形貌和电化学性能。结果表明,Li₄Ti₅O₁₂表面包覆的Cu与C提高了Li₄Ti₅O₁₂电极材料的导电率,其循环性能和倍率性能得到有效地改善。在0.5C、1C和3C倍率下,经过50次充放电循环,放电比容量分别为168.2、160、140.6 mAh·g^-1,其容量保持率分别为88.7%、84.4%、71.2%。电化学阻抗测试表明,表面包覆的Cu与C使其电荷转移阻抗大幅度减少。     

Improved electrochemical performance of sol–gel method prepared Na4Mn9O18 in aqueous hybrid Na-ion supercapacitor

The rod-like Na₄Mn₉O₁₈ material was prepared by sol–gel method and compared with a similar material produced by solid-state method. Their electrochemical properties were examined in aqueous sodium-ion electrolyte cells. The resulting Na₄Mn₉O₁₈ materials were characterized by SEM, TGA, and XRD techniques. The analysis shows that the rod-like Na₄Mn₉O₁₈ has a small particle diameter ranging from 0.2 to 1 μm. The electrochemical performance was characterized by cyclic voltammetry and galvanostatic charge–discharge test in aqueous Na-ion cells with active carbon (AC) as counter electrode. The Na₄Mn₉O₁₈ materials prepared at 800 °C show a high specific capacity of about 200 F g^?1 at a current density of 200 mA g^?1. The Na₄Mn₉O₁₈/Na₂SO₄/AC Na-ion hybrid supercapacitor exhibits excellent cycle performance through 4,000 cycles with 84 % capacity remaining at 500 mA g^?1 charge–discharge current density (an 18 C rate).     

High-capacity Li(Ni0.5Co0.2Mn0.3)O2 lithium-ion battery cathode synthesized using a green chelating agent

Quasi-spherical (Ni_0.5Co_0.2Mn_0.3)(OH)₂ precursor is prepared via a continuous hydroxide co-precipitation method using sodium lactate as the green chelating agent. A layered structure Li(Ni_0.5Co_0.2Mn_0.3)O₂ is synthesized by calcining the mixture of as-prepared precursor and Li₂CO₃ in air. X-ray photoelectron spectroscopy (XPS) indicates that Ni, Co, and Mn exist in the oxidation states of +2/+3, +3 and +4, respectively. The influence of calcination temperature on the structural, morphological, electrochemical properties of Li(Ni_0.5Co_0.2Mn_0.3)O₂ oxides are investigated in detail. As a result, the sample calcined at 850 °C shows excellent electrochemical performance, which could be ascribed to its good crystal structure, low cation disorder, appropriate crystallinity. This sample delivers an initial discharge capacity of 192.6 mA h g^?1 with a coulombic efficiency of 89.5 % at a current density of 20 mA g^?1, and exhibits good rate capability and stable cyclability. Finally, the electrochemical performance of the sodium lactate-derived sample is briefly compared with those of the oxalic acid-derived and ammonia-derived oxide.     

P2‐NaCo0.5Mn0.5O2 as a Positive Electrode Material for Sodium‐Ion Batteries

As a promising positive electrode material for sodium‐ion batteries (SIBs), layered sodium oxides have attracted considerable attention in recent years. In this work, stoichiometric P2‐phase NaCo_0.5Mn_0.5O₂ was prepared through the conventional solid‐state reaction, and its structural and physical properties were studied in terms of XRD, XPS, and magnetic susceptibility. Furthermore, the P2‐NaCo_0.5Mn_0.5O₂ electrode delivered a discharge capacity of 124.3 mA h g^?1 and almost 100 % initial coulombic efficiency over the potential window of 1.5–4.15 V. It also showed good cycle stability, with a reversible capacity and capacity retention reaching approximately 85 mA h g^?1 and 99 %, respectively, at the 5 C rate after 100 cycles. Additionally, cyclic voltammetry and ex situ XRD were employed to explain the electrochemical behavior at the different electrochemical stages. Owing to the applicable performances, P2‐NaCo_0.5Mn_0.5O₂ can be considered as a potential positive electrode material for SIBs.     

Effect of Al2O3 -coating on the electrochemical performances of Li3V2(PO4)3/C cathode material

The effect of Al₂O₃ -coating on Li₃V₂(PO₄)₃/C cathode material for lithium-ion batteries has been investigated. The crystalline structure and morphology of the synthesized powders have been characterized by XRD, SEM, and HRTEM, and their electrochemical performances are evaluated by CV, EIS, and galvanostatic charge/discharge tests. It is found that Al₂O₃ -coating modification stabilizes the structure of the cathode material, decreases the polarization of electrode and suppresses the rise of the surface film resistance. Electrochemical tests indicate that cycling performance and rate capability of Al₂O₃-coated Li₃V₂(PO₄)₃/C are enhanced, especially at high rates. The Al₂O₃-coated material delivers discharge capacity of 123.03 mAh g^?1 at 4 C rate, and the capacity retention of 94.15 % is obtained after 5 cycles. The results indicate that Al₂O₃ -coating should be an effective way to improve the comprehensive properties of the cathode materials for lithium-ion batteries.     

The electrochemical properties of Fe- and Ni-cosubstituted Li2MnO3 via combustion method

The Co-free Li_1.20Mn_0.54Ni _x Fe _y O₂ (x/y?=?0.5, 1.0, 2.0) materials were synthesized by combustion method. The effects of the preparation condition on the structure, morphology, and electrochemical performance were investigated by X-ray diffractometry, scanning electron microscopy, charge–discharge tests, and cyclic voltammetry (CV). The results indicate that the structure and electrochemical characteristics are sensitive to the preparation condition when a large amount of Fe is included. A pure layered α-NaFeO₂ structure with R-3m space group and the discharge capacities of over 200 mAh g^?1 were observed in some as-prepared cathode materials. Particularly, the Li_1.2Mn_0.54Ni_0.13Fe_0.13O₂ prepared by mixing an excess amount of lithium and by firing at 600 °C exhibits a second discharge capacity of 264 mAh g^?1 in the voltage range of 1.5–4.8 V under current density of 30 mA g^?1 at 30 °C and discharge capacity of 223 mAh g^?1 at 2.0–4.8 V. Nevertheless, an unpleasant capacity fading was observed and is primarily ascribed to transformation from a rock-layered structure into a spinel one according to CV testing.     

Lithium‐Rich Layered Oxide Li1.18Ni0.15Co0.15Mn0.52O2 as the Cathode Material for Hybrid Sodium‐Ion Batteries

Li‐rich layered oxide Li_1.18Ni_0.15Co_0.15Mn_0.52O₂ (LNCM) is, for the first time, examined as the positive electrode for hybrid sodium‐ion battery and its Na⁺ storage properties are comprehensively studied in terms of galvanostatic charge–discharge curves, cyclic voltammetry and rate capability. LNCM in the proposed sodium‐ion battery demonstrates good rate capability whose discharge capacity reaches about 90 mA h g^?1 at 10 C rate and excellent cycle stability with specific capacity of about 105 mA h g^?1 for 200 cycles at 5 C rate. Moreover, ex situ ICP‐OES suggests interesting mixed‐ions migration processes: In the initial two cycles, only Li⁺ can intercalate into the LNCM cathode, whereas both Li⁺ and Na⁺ work together as the electrochemical cycles increase. Also the structural evolution of LNCM is examined in terms of ex situ XRD pattern at the end of various charge–discharge scans. The strong insight obtained from this study could be beneficial to the design of new layered cathode materials for future rechargeable sodium‐ion batteries.     

Die Kristallstruktur von Mn15Si26

Zusammenfassung Neben dem bereits bekannten Mangansilicid Mn₁₁Si₁₉ (MnSi_1,727) werden folgende neue Verbindungen des Typs Mn _n Si_2n–m nachgewiesen: Mn₂₆Si₄₅ (MnSi_1,730), Mn₁₅Si₂₆ (MnSi_1,733) und Mn₂₇Si₄₇ (MnSi_1,741). Die Kristallstruktur von Mn₁₅Si₂₆ wird mit Hilfe von Fourier-und Differenz-Fourier-Synthesen bestimmt. Die Gitterparameter für die tetragonale Elementarzelle betragena=5,525 undc=65,55 Å.

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Besides the manganese silicide Mn₁₁Si₁₉ (MnSi_1.727) already reported, the following compounds of the general formula Mn _n Si_2n–m have been observed: Mn₂₆Si₄₅ (MnSi_1.730), Mn₁₅Si₂₆ (MnSi_1.733), and Mn₂₇Si₄₇ (MnSi_1.741). The crystal structure of Mn₁₅Si₂₆ has been determined by means of Fourier-and Fourier-difference-synthesis. The lattice parameters for the tetragonal unit cell have been found to be:a=5.525 andc=65.55 Å.