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Electrical transport properties of the R 3 Ag 4 Sn 4 (R = Gd, Tb, Dy, Ho) intermetallics crystallized in the orthorhombic Gd 3 Cu 4 Ge 4 structure type (space group Immm ) were studied in the temperature interval 11-300 K. Measurements of the temperature dependencies of electrical resistivity ( r ( T )) showed that all the studied compounds are characterized by metallic type of conductivity. The slope change of the resistivity at low temperature part of r ( T ) dependencies for Gd 3 Ag 4 Sn 4 , Tb 3 Ag 4 Sn 4 and Dy 3 Ag 4 Sn 4 compounds is connected with their magnetic ordering. Change of the resistivity caused by magnetic ordering was not observed for the Ho 3 Ag 4 Sn 4 compound in the studied temperature interval. Relation between magnetic and electric properties of the investigated R 3 Ag 4 Sn 4 compounds was analyzed.

A new type of chalcogenide semiconductors possessing different laser operated optoelectronic features is studied for the AgGaGeS4–AgGaGe3Se8 crystalline system give a rare opportunity to form continuous solid solution series based on the substrate compounds. This one allow to perform efficient operation by their optical and electronic features using an external laser light due to presence of huge number of intrinsic defects and high electron-phonon anharmonicities [1] . With accordance to previously reported method were prepared specimens of high quality and homogenous in centimeter range (confirmed by SEM and EPMA) AgGaGeS4 and AgGaGe3Se8 single crystals and the series of intermediate solid solution, in particular AgGaGe1.8S2.4Se3.2, AgGaGe2S2Se4 and AgGaGe2.2S1.6Se4.8. The investigated Ag-Ga-Ge-(S,Se) crystals and solid solutions posses high non-linear optical efficiencies as well as high birefringence that make them efficient for coherent laser frequency conversion in the near-infrared spectral range. So they may be promising for the coherent laser frequency convertors. To expand the possibilities of applications as pressure sensors, optical triggers, modulators or radiation detectors and for better understanding of relation between composition-structure-properties for these materials we perform the complex investigation of temperature dependences of the transparency, photoconductivity, rise and decreasing photocurrent relaxation for determination parameters of localized states and temperature dependent, photoinduced piezoelectric properties.

The electrochemical hydrogenation of Mg-based solid solution phase with Mg76Li12Al12 composition was studied by various electrochemical methods. The Mg76Li12Al12Hx (0

The interaction of components in the Dy-Sm-Ge system at 873 K was investigated by means of x-ray phase and structural analyses, microstructural analysis and energy dispersive x-ray spectroscopy. The existence of the continuous solid solutions between the isostructural binary germanides of the Dy1−xSmxGe (CrB-type), Dy5-xSmxGe4 (Sm5Ge4-type) and Dy5-xSmxGe3 (Mn5Si3-type) were established. The limited solid solutions based on the binary germanides of the SmGe2 (α-ThSi2-type), DyGe2 (TbGe2-type) and Dy11Ge10 (Ho11Ge10-type) are formed. The solubility of Dy in SmGe2 is 15 at.%, Sm in DyGe2 and Dy11Ge10 − 10 at.%, Sm. Two ternary SmxDy1−xGe1.5 (x = 0.15-0.50) and Sm2Dy2Ge7 compounds were found. SmxDy1−xGe1.5 crystallizes in AlB2 structure type. The crystal structure of the new ternary compound of the Sm2Dy2Ge7 (ordered superstructure to Nd4Ge7-type, Pearson symbol oS44, space group C2221, a = 0.5942(1), b = 1.3823(4), c = 1.1801(3) nm, V = 0.9694 nm3) was investigated by means of x-ray single crystal diffraction. The germanium atoms form 3D anionic network the existence of which was confirmed by electronic structure calculations.

In this study, attention was directed at the interactions between Li-doped ZnO systems and rye cereal. The interaction of cereal grains and straws with the transition metal ions is of biochemical importance primarily due to the presence of those complexes in biological systems. Metal/cereal chemistry plays a crucial role in the cross-linking of various biomolecules, and formed systems seem to be promising for various applications, such as material for the production of carbonizate and gaseous substances, which allows for the preparation of second generation biofuels. In the study of cereal/metal complexes, thermogravimetric measurements were performed in order to explain the influence of ZnO and Li2xZn1−xO oxides on the thermal decomposition of rye grains in relation to their application for biofuel production. The possibility of generation of volatile products and carbonizate was considered. The characterization of carbonizate and volatile products was made. The catalytic properties of Li2xZn1−xO phases in the decomposition of cereal grains were confirmed through thermal analysis. The thermal degradation of rye grains was catalyzed by Li-doped ZnO systems. Superior degradation to volatile products depended upon both the botanical origin of the cereal and the catalyzing system.

Magnesium alloys are the basis for the creation of light and ultra-light alloys. They have attracted attention as potential materials for the accumulation and storage of hydrogen, as well as electrode materials in metal-hydride and magnesium-ion batteries. The search for new metal hydrides has involved magnesium alloys with rare-earth transition metals and doped byp- ors-elements. The synthesis and characterization of a new quaternary carbide, namely dimagnesium lithium aluminium carbide, Mg1.52Li0.24Al0.24C0.86, belonging to the family of hexagonal close-packed (hcp) structures, are reported. The title compound crystallizes with hexagonal symmetry (space groupP\overline{6}m2), where two sites with \overline{6}m2 symmetry and one site with 3m. symmetry are occupied by an Mg/Li statistical mixture (in Wyckoff position 1a), an Mg/Al statistical mixture (in position 1d) and C atoms (2i). The cuboctahedral coordination is typical for Mg/Li and Mg/Al, and the C atom is enclosed in an octahedron. Electronic structure calculations were used for elucidation of the ability of lithium or aluminium to substitute magnesium, and evaluation of the nature of the bonding between atoms. The presence of carbon in the carbide phase improves the corrosion resistance of the Mg1.52Li0.24Al0.24C0.86alloy compared to the ternary Mg1.52Li0.24Al0.24alloy and Mg.

Phase equilibria in the Li–B–C ternary system have been investigated by X-ray powder diffraction, scanning electron microscopy, electron probe microanalysis and differential scanning calorimetry. The isothermal section of the phase diagram has been constructed over the whole concentration range at 400 °C. The Li–B–C system is characterized by the formation of six ternary compounds: τ1 – LiBC3, τ2 – LiB2C2, τ3 – LiBC, τ4 – Li2B2C, τ5 – LiB6C and τ6 – LiB13C2. The formation of the new ternary compound LiB2C2 (own structure type, space group P63/mmc, a = 2.5930(3) A, c = 22.680(1) A) and binary BC3 (space group Pm2, a = 2.4588(4) A, c = 6.770(2) A) has been revealed. The crystal structures are discussed in the light of the underlying graphene and heterographene networks.

The maximally disordered (MD) phases with the general formula Y5−xPrxSb3−yMy (M = Sn, Pb) are formed with partial substitution of Y by Pr and Sb by Sn or Pb in the binary Y5Sb3 compound. During the electrochemical lithiation and sodiation, the formation of Y5-xPrxSb3-yMyLiz and Y5−xPrxSb3−yMyNaz maximally disordered–high entropy intermetallic phases (MD-HEIP), as the result of insertion of Li/Na into octahedral voids, were observed. Carbon nanotubes (CNT) are an effective additive to improve the cycle stability of the Y5−xPrxSb3−yMy (M = Sn, Pb) anodes for lithium-ion (LIBs) and sodium-ion batteries (SIBs). Modification of Y5−xPrxSb3−ySny alloys by carbon nanotubes allowed us to significantly increase the discharge capacity of both types of batteries, which reaches 280 mAh · g−1 (for LIBs) and 160 mAh · g−1 (for SIBs), respectively. For Y5−xPrxSb3−yPby alloys in which antimony is replaced by lead, these capacities are slightly smaller and are 270 mAh · g−1 (for LIBs) and 155 mAh · g−1 (for SIBs), respectively. Results show that structure disordering and CNT additives could increase the electrode capacities up to 30% for LIBs and up to 25% for SIBs.

The equiatomic rare earth iridium indides REIrIn (RE=La, Pr, Nd, Er–Yb) were synthesized by reaction of the elements in induction or muffle furnaces and were characterized through X-ray powder patterns. The structures of LaIr0.86In1.14, PrIr0.89In1.11, NdIr0.94In1.06, ErIrIn (all ZrNiAl type, P6̅2m), and YbIrIn (TiNiSi type, Pnma) were refined from single crystal X-ray diffractometer data. Refinements of the occupancy parameters revealed small degrees of solid solutions with indium substitution on the iridium sites. Chemical bonding analyses and electronic structure calculations indicate the dominance of metallic bonding in addition to partial ionic interactions between the cations and polyanions, as well as covalent contributions between the indium and iridium atoms.

The isothermal sections of the Nd–Mg–Co phase diagram at 300 and 500 °C have been constructed on the basis of X-ray diffraction (XRD), Wavelength Dispersive Spectrometry (WDS) and Electron Probe Micro Analyzer (EPMA) analysis. The existence of two ternary compounds Nd 4 Mg 3 Co 2 (own structure type) and Nd 4 MgCo (Gd 4 RhIn type) was confirmed. The latter has homogeneity range defined as Nd 4- x Mg 1+ x Co with 0 ≤ x ≤ 0.2 at 300 °С and 0 ≤ x ≤ 0.3 at 500 °С. Four new ternary compounds were identified in this work: Nd 23- x Mg 4+ x Co 7 (Pr 23 Mg 4 Ir 7 type; −1.5 ≤ x ≤ 0.1 at 300 °С and −0.6 ≤ x ≤ 0.3 at 500 °С); NdMg 2 Co 9 (YIn 2 Ni 9 type), ∼Nd 77 Mg 14 Co 9 (cubic) and ∼Nd 56 Mg 6 Co 38 (unknown crystal structure). Two binary compounds, NdCo 2 and NdCo 3 , were found to dissolve significant amount of Mg with the formation of substitutional solid solutions Nd 1- x Mg x Co 2 (MgCu 2 type; x ≤ 0.1 at 300 °С and x ≤ 0.15 at 500 °C) and Nd 1- x Mg x Co 3 (PuNi 3 type; x ≤ 0.33 at 300 °С and x ≤ 0.5 at 500 °C), respectively. The Nd 4 Mg 3 Co 2 , Nd 4- x Mg 1+ x Co, Nd 23- x Mg 4+ x Co 7 and Nd 1- x Mg x Co 2 compounds irreversibly absorb hydrogen at room temperature and pressure 1–10 bar to form crystalline or amorphous hydrides with hydrogen content 1.6–2.1 wt. %. Hydrogen thermal desorption from these hydrides in vacuum results in their disproportionation with formation of binary NdH 2 hydride. The Nd 1- x Mg x Co 3 (0 ≤ x ≤ 0.5) alloys reversibly absorb up to 1.3 wt. % of hydrogen. NdMg 2 Co 9 compound has small hydrogenation capacity, absorbing only 0.5 wt. % at room temperature and hydrogen pressure 185 bar.

Alloys from the ternary Li–Al–Sn system have been investigated with respect to possible applications as negative electrode materials in Li-ion batteries. This led to the discovery of a new ternary compound, a superstructure of the Li13Sn5binary compound. The ternary stannide, Li9Al4Sn5(nonalithium tetraaluminium pentastannide; trigonal,P\overline{3}m1,hP18), crystallizes as a new structure type, which is an ordered variant of the binary Li13Sn5structure type. One Li and one Sn site have \overline{3}m. symmetry, and all other atoms occupy sites of 3m. symmetry. The polyhedra around all types of atoms are rhombic dodecahedra. The electronic structure was calculated by the tight-binding linear muffin-tin orbital atomic spheres approximation method. The electron concentration is higher around the Sn and Al atoms, which form an [Al4Sn5]m−polyanion.

For the first time phase equilibria and phase diagram of the AgGaS 2 –SiS 2 system were successfully explored by differential thermal and X-ray phase analysis methods. Crystal structure of low-temperature (LT) modification of Ag 2 Ga 2 SiS 6 (LТ- Ag 2 Ga 2 SiS 6 ) was studied by X-ray powder method and it belongs to tetragonal space group I-42d, with unit cell parameters a=5.7164(4) A, c=9.8023(7) A, V=320.32(7) A 3 . Additional details regarding the crystal structure exploration are available at the web page Fachinformationszentrum Karlsruhe. X-ray photoelectron core-level and valence-band spectra were measured for pristine LТ- Ag 2 Ga 2 SiS 6 crystal surface. In addition, the X-ray photoelectron valence-band spectrum of LТ-Ag 2 Ga 2 SiS 6 was matched on a common energy scale with the X-ray emission S Kβ 1,3 and Ga Kβ 2 bands, which give information on the energy distribution of the S 3p and Ga 4p states, respectively. The presented X-ray spectroscopy results indicate that the valence S p and Ga p atomic states contribute mainly to the upper and central parts of the valence band of LТ-Ag 2 Ga 2 SiS 6 , respectively, with a less significant contribution also to other valence-band regions. Band gap energy was estimated by measuring the quantum energy in the spectral range of the fundamental absorption. We have found that energy gap Eg is equal to 2.35 eV at 300 K. LT-Ag 2 Ga 2 SiS 6 is a photosensitive material and reveals two spectral maxima on the curve of spectral photoconductivity spectra at λ max1 =590 nm and λ max2 =860 nm. Additionally, linear electro-optical effect of LT-Ag 2 Ga 2 SiS 6 for the wavelengths of a cw He-Ne laser at 1150 nm was explored.

Reaction of 3-aryl-2-chloropropanal with 1-arylsulfonylpropan-2-ones in aqueous ammonia and alcohol under the conditions of Hantzsch pyrrole synthesis led to the selective formation of the products of interrupted Feist-Benary reaction, 2-(R-benzyl)-4-arylsulfonyl-5-methyl-2,3-dihydrofuran-3-ols.

The crystal structure of the high-temperature modification of the compound Li

The synthesis, structural characterization, and chemical bonding peculiarities of new intermetallic compounds from Y–Mg–Ni ternary system are reported herein. The crystal structures of these compounds were determined by single-crystal and X-ray powder diffraction analysis. Three ternary compounds were studied: Y2Mg11Ni2 [own structure type, monoclinic, Pearson Symbol mS30, Space Group C2/m, a=18.969(4), b=3.6582(7), c=11.845(2) Å, β=125.07(3)°], Y4Mg3Ni2 [Ru4Al3B2 structure type, tetragonal, P4/mmm, tP18, a=10.8668(2), c=3.59781(12) Å] and YMgNi [MoAlB structure type, orthorhombic, Cmcm, a=3.6713(4), b=17.708(3), c=3.9583(5) Å]. New compositions of Y1− x Mg x Ni4 and Y5− x Mg24+ x solid solutions were detected: YMg0.86(1)Ni4.14(1) [SnMgCu4 structure type, cubic, F4̅3m, cF24, a=7.0747(6) Å] and Y4.28(1)Mg24.72(1) [Ti5Re24 structure type, cubic, I4̅3m, cI58, a=11.2655(11) Å]. The crystal structure peculiarities of these compounds are discussed. A particular attention has been given to Y2Mg11Ni2 and its relations with other Mg-containing compounds. Crystallographic analysis together with linear muffin-tin orbital band structure calculations reveals the presence of [Y2Ni4@Mg20] and [Y4Ni2@Mg18] clusters in Y2Mg11Ni2 phase. For Y4Mg3Ni2 the formation of the Ni–Mg nets was observed, while the Y atoms form a monolayer.

The bromination of multi-walled carbon nanotubes (MWCNT) was performed with vapor bromine in a closed vessel, and they were subjected to intensive stirring with a magnetic stirrer for up to 14 days. The efficiency of bromination was compared depending upon duration. The structure and surface of the crude and purified products were characterized by detailed physicochemical analyses, such as SEM/EDS, TEM, XRD, TGA, Raman, and XPS spectroscopies. The studies confirmed the presence of bromine covalently bound with nanotubes as well as the formation of inclusion MWCNT–Br2 complexes. It was confirmed that Br2 molecules are absorbed on the surface of nanotubes (forming the CNT-Br2 complex), while they can dissociate close to dangling bonds at CNT defect sites with the formation of covalent C−Br bonds. Thus, any covalent attachment of bromine to the graphitic surface achieved around room temperature is likely related to the defects in the MWCNTs. The best results, i.e., the highest amount of attached Br2, were obtained for brominated nanotubes brominated for 10 days, with the content of covalently bound bromine being 0.68 at% (by XPS).

The structure of hydrogen sublattice of the Mg2NiH0.3 phase has been studied by computational methods to overcome some ambiguities of the experimental method. Seven types of possible hydrogen sites (marked as X1 to X7) were found. Models with occupation of X1 or X2+X3 sites were found in the literature. Further analysis of geometry and electronic density of the Mg2Ni compound revealed three additional types of voids X4-X6. Models having from 1 to 3 hydrogen atoms per unit cell were tested. The optimization of some of the models with occupied X2 and X5 sites led to shift of hydrogen atoms into the new type of voids X7. It was revealed that two the most energetically favorable ordered models have two types of tetrahedral sites occupied by hydrogen: X3 (H@Mg3Ni) and X7(H@Mg2Ni2). It was suggested that the real structure was a superposition of these models with either two X3 or both X3+X7 voids occupied. The developed structure is close to and has the advantage over one of the models mentioned in the literature, since the trigonal X2 site presented in the literature model is split here into two adjacent tetrahedral X7 sites.

The electrochemical hydrogenation, structure and thermal stability of LaNi4·6Zn0.4-xLix (x ≤ 0.2) intermetallic compounds have been investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) with WDS/EDX, differential scanning calorimetry (DSC) and electrochemical techniques: potentiodynamic polarization, charge/discharge, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS). The synthesized LaNi4·6Zn0.4-xLix intermetallics are solid solutions on the basis LaNi5 compound with hexagonal CaCu5 structure type. Precise structural studies by single crystal methods revealed that with the increase of lithium content in the phase, the hexagonal unit cell is transformed into a new orthorhombic structure (Cmmm, a = 5.0068 (10), b = 8.6719 (17) A, c = 3.9952 (8) A). The LaNi4·6Zn0.4-xLix intermetallics effectively passivate in 6 M KOH over a wide potential range. The presence of lithium in the solid solution phase improves corrosion resistance of LaNi4·6Zn0.4-xLix intermetallics compared to the reference compound (LaNi5). The electrochemical measurements show that LaNi4·6Zn0.4-xLix intermetallic compounds absorb hydrogen, and the highest effectiveness of hydrogen absorption shows LaNi4·6Zn0·2Li0.2 compound with orthorhombic structure. The DSC/TG results indicate greater thermal stability of compounds doped by Zn (LaNi4·6Zn0.4) and Zn/Li (LaNi4·6Zn0·2Li0.2) in compare to LaNi5.

This paper concentrates on electrochemical properties of groups of multi-walled carbon nanotubes (MWCNT) functionalized with substituents containing a stereogenic heteroatom bonded covalently to the surface of the carbon nanotube. This system was tested in Swagelok-type cells. The cells comprised a system (functionalized CNT with salts containing S and P atoms) with a working electrode, microfiber separators soaked with electrolyte solution, and a lithium foil counter/reference (commercial LiCoO2) electrode. The electrolyte solution was 1 M LiPF6 in propylene carbonate. Using standard techniques (cyclic voltammetry/chronopotentiometry), galvanostatic cycling was performed on the cells at room temperature with a CH Instruments Model 600E potentiostat/galvanostat electrochemical measurements. Methods of functionalization CNT were compared in terms of the electrochemical properties of the studied systems. In all systems, the process of charge/discharge was observed.

The synthesis, isothermal section at 450 °C of the Li-Ge-H system in the concentration region from 40 at.% Li to 70 at.% Li and structural characterizations of the observed phases are reported. The hydrogenation and structural properties of the LiGeHx (0 < x < 0.25) phase were studied by volumetric analysis and X-ray diffraction. The absorption of hydrogen by LiGe binary compound produce the ternary hydride phase LiGeHx (0 < x < 0.25), thus the volume tetragonal unit cell increases on 1.8 A3. The LiGeHx solid solution is formed by means of the insertion of hydrogen atoms into tetrahedral voids of parent LiGe structure. The extension of homogeneity range of LiGeHx (0 < x < 0.25) phase and its crystal structure were more precisely refined using X-ray diffraction data. Electronic structure calculations reveal an increased occupation of electronic states at the Fermi level for LiGeHx in comparison to LiGe.

Binary and multicomponent intermetallic compounds based on lithium andp-elements of Groups III–V of the Periodic Table are useful as modern electrode materials in lithium-ion batteries. However, the interactions between the components in the Li–Ge–B ternary system have not been reported. The structure of tetralithium digermanium boride, Li4Ge2B, exhibits a new structure type, in the noncentrosymmetric space groupR3m, in which all the Li, Ge and B atoms occupy sites with 3msymmetry. The title structure is closely related to the Mo2B5and Li5Sn2structure types, which crystallize in the centrosymmetric space groupR\overline{3}m. All the atoms in the title structure are coordinated by rhombic dodecahedra (coordination number = 14), similar to the atoms in related structures. According to electronic structure calculations using the tight-binding–linear muffin-tin orbital–atomic spheres approximation (TB–LMTO–ASA) method, strong covalent Ge—Ge and Ge—B interactions were established.

The lithiation and magnesiation of binary R5Sn3 (R = Y and Gd) phases has been studied by XRD, SEM, EPMA and electrochemical methods. The formation of R5Sn3Lix and R5Sn3Mgx ternary hexagonal phases as the results of insertion of Li/Mg into octahedral voids were observed during the first stage of electrochemical lithiation and magnesiation respectively. During the second stage of the electrochemical lithiation and magnesiation is the decomposition of the hexagonal phase into new phases and substitution of tin atoms by Li/Mg are observed.

Phase diagrams of the AgGaSe2–SiSe2 system were explored by differential thermal analysis (DTA) and X-ray diffraction (XRD) analysis methods for the first time. It was demonstrated that the investigated system forms quaternary compounds of compositions Ag2Ga2SiSe6 and AgGaSiSe4. Ag2Ga2SiSe6 melts at 1042 K and exists in two polymorphous modifications. The crystal structure of the low-temperature modification was determined by the single crystal method (space group I2d (122) and lattice parameters a = 5.9021(1) A, b = 5.9021(1) A, and c = 10.4112(10) A). Additional details (CIF file) regarding the crystal structure investigations are available at the Fachinformationszentrum Karlsruhe. The band gap (Eg) of the Ag2Ga2SiSe6 system was estimated from the fundamental absorption edge and we showed that it decreases with increasing temperature (100–300 K) from 2.13 eV to 1.97 eV. The compound is photosensitive and its spectral dependence on the photoconductivity has two maxima: at λmax1 = 640 nm and λmax2 = 900 nm. For the pristine Ag2Ga2SiSe6 crystal surface, X-ray photoelectron core-level and valence-band spectra were obtained. The X-ray photoelectron valence-band spectrum of Ag2Ga2SiSe6 was compared on a common energy scale with the X-ray emission Se Kβ2 and Ga Kβ2 bands, representing peculiarities of the energy distribution of the Se 4p and Ga 4p states, respectively. The comparison revealed that the principal contributions of the valence Se p and Ga p states occur in the upper and central parts of the valence band, respectively, with significant contributions to other valence band regions. The illumination by the bicolour coherent pulses of the Er:glass nanosecond lasers at different angles led to the formation of the gratings, which are sensitive to the irradiation time.

A new concept to prepare Maximally Disordered – High Entropy Intermetallic Phases (MD-HEIP) with the general formula of Gd1-xLaxSn2-ySbyMz (M = Li, Na, Mg) based on two mechanisms of substitution and insertion is proposed. As a result of the substitution of Gd by La and Sn by Sb in the binary GdSn2 compound, a maximally disordered (MD) phase of Gd1-xLaxSn2-ySby was formed. The formation of Gd1-xLaxSn2-ySbyLiz and Gd1-xLaxSn2-ySbyMgz HD-HEIP phases as the result of additionally inserting Li/Mg into tetragonal antiprismatic voids is observed during the electrochemical lithiation and magnesiation, respectively. The Gd1-xLaxSn2-ySbyNaz phase was formed by partial substitution of Sn atoms by Na atoms. The Gd1-xLaxSn2-ySby and Gd1-xLaxSn2-ySbyMz phases have been studied by XRD, SEM, EPMA, Sn Mossbauer spectroscopy, 7Li NMR, electrochemical techniques, magnetization and heat capacity measurements. The electrochemical studies of cyclic characteristics show that the MD-HEIP electrodes are rapidly activated (5–6 cycles) and continue to work steadily, almost without losing capacity. The MD phases of Gd1-xLaxSn2-ySby and Gd1-xLaxSn2-ySbyNaz show very similar behaviour of physical properties. Both MD phases of Gd1-xLaxSn2-ySby and Gd1-xLaxSn2-ySbyNaz have a comparably strong mean field antiferromagnetic coupling (θ around −41 K) and show typical Currie-Weiss paramagnetic behaviour of localized Gd magnetic moments down to ∼20 K. Both MD – HEIP Gd1-xLaxSn2-ySbyMz (M = Li and Mg) samples show a lowered antiferromagnetic mean field coupling (θ around −13 K) compared to MD phases.

The new quaternary aluminide Li

The isothermal section of the Sm–Cu–Mg system at 670 K was studied in the 0–50 at.% Mg concentration range. The phase analysis was carried out by scanning electron microscopy (SEM), electron probe microanalysis (EPMA), wavelength dispersive spectrometry (WDS) and X-ray powder diffraction (XRPD) techniques. The X-ray single crystal and powder analysis were used for structure investigations. Of the nine ternary phases (τ 1 –τ 9 ) which were found to exist in this section are seven new phases, τ 1 – Sm 60.1 Cu 26.4 Mg 13.5 , τ 3 – Sm 22.5 Cu 74.3 Mg 3.2 , τ 4 – SmCu 4 Mg, τ 5 – SmCuMg, τ 6 –SmCuMg 2 , τ 7 – Sm 81.2 Cu 10.3 Mg 8.5 and τ 8 – Sm 4 Cu 10 Mg 3 , and two known phases, τ 2 – Sm 2 Cu 2 Mg and τ 9 – SmCu 9 Mg 2 . As the result of our investigation the crystal structures of τ 2 , τ 4 , τ 5 , τ 6 and τ 8 phases have been established. Moreover, it has been found that the solubility of Mg and Cu in Sm–Cu and Sm–Mg binary phases, respectively, is insignificant, and that the maximum solubility takes place in the case of Cu 2 Mg phase, which dissolves up to 5 at.% Sm.

The isothermal section of the Tb–Mg–Co phase diagram at 500 °C has been built on the basis of XRD analysis of forty samples prepared by powder metallurgy. The existence of two ternary compounds Tb4Mg3Co2 and Tb4MgCo was confirmed. The formation of two solid solutions, Tb1−xMgxCo3 (0≤x≤0.4) and Tb1-−xMgxCo2 (0≤x≤0.6), was found for the first time. It is shown that Tb5Mg24 also dissolves a small amount of Co. Other binary compounds do not dissolve the third component. The Tb4MgCo and TbMgCo4 compounds form hydrides (12.7 and 5.3 at.H/f.u. capacity, respectively) that retain the original structure of metallic matrices. Upon thermal desorption the Tb4MgCoH12.7 hydride was stable up to 300 °C and disproportionated at higher temperature. Two other hydrides, Tb4Mg3Co2H∼4 and Tb2MgCo9H12, are unstable in air and decompose into the initial compounds.

The phase diagram of the Li-Bi binary system was amended by x-ray analysis and differential scanning calorimetry. The formation of the binary compound Li2Bi was confirmed and its structure determined by x-ray single crystal diffraction. The Li2Bi compound crystallizes with the Mg2Ga structure type (space group P-62c, hP18, a = 8.0712(4) A, c = 6.8352(3) A). The analysis of the interatomic distances together with electronic structure calculations using the tight-binding linear muffin-tin orbital atomic spheres approximations (TB-LMTO-ASA) indicate the dominance of a metallic type of bonding, although there is a weak partially ionic bonding, caused by charge transfer from Li to Bi.

A series of five LaNi4.6Zn0.4−xSnx alloys (x = 0–0.4) has been investigated in view of their electrochemical hydrogen capacity and exchange current density of H2O/H2 system. The hydrogenation parameters are similar to those of LaNi5 parent compound when part of nickel is substituted either with Zn or with Sn. Simultaneous presence of Zn and Sn reveals its synergistic outcome and is prone to evident improvement of alloy hydrogenation properties.

The chromium-substituted LiCr x Ni1−x O2 oxides were prepared from lithium hydroxide monohydrate (LiOH·H2O), NiO, and Cr2O3. The structure of Li1.5Cr0.5NiO3 phase has been investigated by means of X-ray single crystal and powder diffraction (space group P-3m1, a = 2.9256(1), c = 7.1539(2) A). The relations between Li1.5Cr0.5NiO3 structure, rhombohedral LiNiO2, and NiO are described by a group-subgroup scheme on the basis of Barnighausen formalism. Electronic structures were calculated applying the TB-LMTO-ASA 4.7 program. The maximum of electron localization function (ELF) was obtained around the oxygen atoms. Features of the crystal structure of the trigonal Li1.5Cr0.5NiO3 phase cause lower electrode capacity compared to rhombohedral LiNiO2.

The Zr5Sn3 intermetallic compound has been studied as a possible anode material for lithium- and magnesium-ion batteries. The Zr5Sn3Li x electrodes provide a reversible specific capacity of 160–140 mAh g−1, whereas Zr5Sn3Mg x electrodes yield a slightly lower capacity of 110–95 mAh g−1. The lithiation and magnesiation of Zr5Sn3 were investigated by means of X-ray, scanning electron microscopy, microprobe analyses, and electrochemical measurements. The electrochemical lithiation and magnesiation occurs in two stages, the first is the insertion of Li/Mg into structural voids, and the second stage is the decomposition of the hexagonal phase into new phases and substitution of tin atoms by Li/Mg.

The phase equilibria of the Ho–Ni–Sn and Er–Ni–Sn ternary systems were studied at 673 K in the whole concentration range using electron probe microanalysis (EPMA) and X-ray powder diffraction (XPD). Each system is characterized by formation of eight ternary compounds at 673 K: Ho 6 Ni 2 Sn, Er 6 Ni 2 Sn (Ho 6 Ni 2 Ga-type), Ho 2 Ni 2 Sn, Er 2 Ni 2 Sn (Mo 2 FeB 2 -type), HoNi 5 Sn, ErNi 5 Sn (CeCu 4.38 In 1.62 -type), HoNi 1.73 Sn, ErNi 1.72 Sn (YbNi 1.705 Sn-type), HoNiSn, ErNiSn (TiNiSi-type), HoNiSn 2 , ErNiSn 2 (LuNiSn 2 -type), HoNiSn 4 , ErNiSn 4 (LuNiSn 4 -type), and Ho 2 NiSn 6 , Er 2 NiSn 6 (Lu 2 NiSn 6 -type). The interstitial solid solutions HoNi x Sn 2 (up to 7 at.% Ni) and ErNi x Sn 2 (up to 5 at.% Ni) based on the RSn 2 (ZrSi 2 -type) binary compounds were found.

Magnesium alloys are the basis for the creation of light and ultra-light alloys. They have attracted attention as potential materials for the accumulation and storage of hydrogen, as well as electrode materials in metal-hydride and magnesium-ion batteries. The search for new metal hydrides has involved magnesium alloys with rare-earth transition metals and doped by p- or s-elements. The synthesis and characterization of a new quaternary carbide, namely dimagnesium lithium aluminium carbide, Mg

Li-B-C alloys have attracted much interest because of their potential use in lithium-ion batteries and superconducting materials. The formation of the new compound LiBC

The structural and thermal stability, electrochemical hydrogenation and corrosion behavior of LaT5−x(M/Li)x (T = Co, Ni and M = Al, Ge) alloys have been investigated using x-ray diffraction, SEM with WDS/EDX, DSC and electrochemical techniques. The prepared ternary and quaternary samples are solid solutions on the base of binary LaCo5 and LaNi5 compounds with hexagonal CaCu5 structure type. By partial substitution of transition metals (Ni and Co) by Al, Ge and Li in the LaT5−x(M/Li)x alloys the discharge capacity increased by 25%. Doping of LaCo5 and LaNi5 binary phases by Al, Ge and Li improves corrosion resistance, thermal stability and absorption capacity during the electrochemical hydrogenation. These alloys passivate effectively in strong alkaline solution.

A novel quaternary mixed halogenide, Tl5Hg2Br5I4, was synthesized by fusion of thallium bromide and mercury iodide in a 5:2 molar ratio. The crystal structure of Tl5Hg2Br5I4represents a new series of composite structures described by the general formulanTlBr*mTl2[HgBr2I2]; in this case,n= 4 andm= 8. Electronic structure calculations indicate that the title compound is a semiconductor.

The synthesis, structural characterization, and chemical bonding peculiarities of three new binary Li–In intermetallides are reported. The crystal structures of these compounds were determined by single-crystal X-ray diffraction analysis. The compositions obtained after structure refinements were Li22–xIn8+x (x = 0.1) [new structure type, monoclinic crystal system, Pearson symbol mS30, space group C2/m, a = 14.156(3), b = 4.729(1), c = 8.617(2) A, β = 105.89(1)°, R1 = 0.0279, wR2 = 0.0583 for 669 reflections], Li11–xIn4+x (x = 1.05) [new structure type, trigonal, Pm1, hP15, a = 4.7480(7), c = 14.283(3) A, R1 = 0.0323, wR2 = 0.0741 for 277 reflections], and Li10–xIn2+x (x = 1.59) [new structure type, hexagonal, P6/mmm, hP12, a = 4.6975(7), c = 11.526(2) A, R1 = 0.0680, wR2 = 0.1358 for 127 reflections]. The Li22–xIn8+x (x = 0.1) structure is related to the structure of lithium (W-type). The structure of Li11–xIn4+x (x = 1.05) can be described as a derivative of the CdI2 type. Li10–xIn2+x (x = 1.59) can be derived from the Li2Pt structure. [In2@Li20] clusters composed of 20 lithium atoms, which surround a In–In pair, are detected in the structure of all three investigated compounds. TB-LMTO (Tight-Binding Linear Muffin-Tin Orbital) calculations indicate strong covalent In–In interactions and the presence of [In2@Li20] clusters in these new binary indides.

The (3+1)-dimensional modulated structure of the LiZn4 − x(x= 0.825) binary compound has been determined in the superspace. The compound crystallizes in the orthorhombic superspace groupCmcm(α00)0s0 witha= 2.7680 (6),b= 4.7942 (6),c= 4.3864 (9) Å, modulation wavevector:q≃ 4/7a*. The structure is a derivative from the hexagonal close packing. The cubo-octahedron as a coordination polyhedron (c.n. = 12) is typical for all atoms. Bonding between atoms is explored by means of theTB-LMTO-ASAprogram package. The absence of strong interatomic interactions in LiZn4 − xis the main reason for the possible structure transformations.

The process of the incorporation of lithium atoms into the binary oxide ZnO and the structure of the ternary phase Li2xZn1–xO have been investigated experimentally (by means of X-ray single-crystal and powder diffraction analyses, differential scanning calorimetry and thermogravimetry) and theoretically (electronic structure calculations with the program TB-LMTO-ASA, TB-LMTO = tight-binding linear muffin-tin orbital). The formation of the disordered Li2xZn1–xO phase occurs under the action of two processes: the inclusion of additional lithium atoms at the 2a site (x = 0, y = 0, z = 0.124) and the the partial substitution of zinc atoms by lithium atoms at the 2b site (x = 1/3, y = 2/3, z = 0.379). At temperatures higher than 700 °C, the ternary phase begins to decompose.