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Molecules of the title compound [systematic name: 2,4'(propane-2,2-diyl)diphenol[, C15H16O2, are linked through intermolecular O-H···O hydrogen bonds into infinite zigzag chains. The molecular structure is compared with that of the related compound 4,4'-isopropylidenediphenol. [ABSTRACT FROM AUTHOR]

Tl5Hg2Br5I4 is prepared by fusion of TlBr and HgI2 in a 5:2 molar ratio (evacuated quartz ampoule, 770 K, 6 h, cooling rate of 10 K/h). [ABSTRACT FROM AUTHOR]

Li1.95Ag1.05In3 is prepared from the elements (Ta crucible, 1100 °C for 15 min followed by annealing at 150 °C for 1 month) and characterized by single crystal XRD and TB-LMTO-ASA computations. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound is determined by single crystal XRD. [ABSTRACT FROM AUTHOR]

Single crystals of the MgZn2Ce alloy (magnesium dizinc cerium) were synthesized by a two-step method which couples the thermal treatment of pressed pellets of the pure elements with subsequent arc melting. The compound crystallizes in a Heusler-type (MnCu2Al) structure in the space group Fm m, with one Zn site (site symmetry 3 m), one Ce and one Mg site (both with m m site symmetry). All interatomic distances indicate metallic type bonding. [ABSTRACT FROM AUTHOR]

The planar benzene rings in the title compound, C15H16O2, are inclined at an angle of 82.61 (9)° to one another. There are two intra­molecular hydrogen bonds of types O—H⋯π and C—H⋯O. The mol­ecules are linked by strong O—H⋯O hydrogen bonds into a one-dimensional network, which is compared with that of related compounds. [ABSTRACT FROM AUTHOR]

The mol­ecules of the title compound, C10H8O2, are linked by two O—H⋯O hydrogen bonds, which form infinite chains with a graph-set descriptor of C(6). These chains are linked into puckered (100) sheets of R44(8) and R44(24) rings. Adjacent sheets are connected by weak C—H⋯π and π–π inter­actions into a continuous three-dimensional network. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of a new ternary dilanthanum lithium hexagermanide, La2LiGe6− x ( x = 0.21), belonging to the Pr2LiGe6 structure type, and a quaternary dilanthanum lithium tetragermanium disilicide, La2LiGe4Si2, which crystallizes as an ordered variant of this type, are reported. In both structures, Li is on a site of mmm symmetry. All other atoms are on sites of m2 m symmetry. These structures are new representatives of a homologous linear structure series based on structural fragments of the AlB2, CaF2 and ZrSi2 structure types. The observed 17-vertex polyhedra are typical for La atoms and the environment of the Li atom is cubic. Two Ge atoms are enclosed in a tetragonal prism with one added atom (nine-vertex polyhedron). The trigonal prismatic coordination is typical for Ge or Si atoms. The metallic nature of the bonding is indicated by the interatomic distances and electronic structure calculations. [ABSTRACT FROM AUTHOR]

Abstract: The crystal structures of two new ternary phases, La4Ag10Mg3 and La4Ag10.3Mg12, were refined from X-ray single crystal diffraction data. La4Ag10Mg3 crystallizes in the Ca4Au10In3 structure type, an ordered variant of the binary Zr7Ni10 compound: orthorhombic, Cmce, oS68, a=14.173(5), b=10.266(3), c=10.354(3)Å, Z=4, wR 2=0.0826, 676 F 2 values, 50 variables. La4Ag10.3Mg12 represents a new structure type: orthorhombic, Cmmm, oS116-10.32, a=9.6130(3), b=24.9663(8), c=9.6333(2)Å, Z=4, wR 2=0.0403, 1185 F 2 values, 101 variables. The structural analysis of both compounds, highlighting a significant contraction of the Ag–Mg distances, suggests the existence of three-dimensional [Ag–Mg] networks hosting La atoms. LMTO calculations applied to La4Ag10Mg3 indicate that the strongest bonds occur for Ag–Ag and Ag–Mg interactions, and confirm the presence of a 3D∞[Ag10Mg3]δ− polyanionic framework balanced by positively charged La atoms. [ABSTRACT FROM AUTHOR]

Abstract: The indides Ce7Ni5±x Ge3±x In6 and Pr7Ni5±x Ge3±x In6 were synthesized from the elements by arc-melting of the components. Single crystals were grown via special annealing sequences. Both structures were solved from X-ray single crystal diffraction data: new structure type, P6/m, Z=1, a=11.385(2), c=4.212(1)Å, wR 2=0.0640, 634F 2 values, 25 variables for Ce7Ni4.73Ge3.27In6 and a=11.355(6), c=4.183(2)Å, wR 2=0.0539, 563F 2 values, 25 variables for Pr7Ni4.96Ge3.04In6. Both indides show homogeneity ranges through Ni/Ge mixing (M sites). This new structure type can be derived from the AlB2 structure type by a substitution of the Al and B atoms by CeM 12 and NiIn6Ce3 polyhedra (tricapped trigonal prism). Magnetic susceptibility measurements on a polycrystalline sample of Ce7Ni5Ge3In6 indicated Curie–Weiss like paramagnetic behavior down to 1.71K with the effective magnetic moment slightly reduced in relation to the value expected for trivalent cerium ions. No magnetic ordering is evident. [ABSTRACT FROM AUTHOR]

Abstract: The novel intermetallic phases TbNiMg and Tb4+x Ni2Mg3−x (x = 0.2) were synthesized by heating in a resistance furnace evacuated quartz vials containing Nb-crucibles with element pieces. Scanning electron microscopy coupled with electron microprobe analysis was performed to check microstructure and phases composition. The crystal structures were refined from X-ray single crystal diffraction data. TbNiMg crystallizes in the MoAlB structure type – orthorhombic, Cmcm, oS12, a = 0.36684(4), b = 1.7721(2), c = 0.39855(4) nm, Z = 4, wR 2 = 0.0861, 171 F 2 values, 14 variables; Tb4+x Ni2Mg3−x crystallizes in the Ru4Al3B2 structure type – tetrahedral, P4/mmm, tP18, a = 1.08878(2), c = 0.36290(1) nm, Z = 2, wR 2 = 0.0995, 310 F 2 values, 24 variables. Interatomic distances in the studied phases indicate metallic type bonding with strong Tb–Ni interactions. Both structures are two-layers. The crystal chemical peculiarities of these compounds are described and compared applying the intergrowth concept on the base of AlB2, CsCl and α-Fe simple fragments. Several two-layer structures, including CrB, ZrSi2, MoAlB and CuGe4Hf2, are described as isomorphic group-subgroup transformation derivatives of the α-U structure by means of the Bärnighausen formalism. [Copyright &y& Elsevier]

Abstract: Single crystals of the Y5Cu5Mg8, Y5Cu5Mg13, Y5Cu5Mg16 and YCuMg4 compounds were synthesized by heating in a resistance furnace evacuated quartz vials containing Ta-crucibles with element pieces. SEM-EDXS analyses were performed to check phases composition. The structures were refined from X-ray single crystal diffraction data. Y5Cu5Mg8, Y5Cu5Mg13 and Y5Cu5Mg16 represent new structure types: Y5Cu5Mg8 – orthorhombic, Pmma, oP36, a =2.63723(15), b =0.40066(2), c =0.74115(6)nm, Z =2, wR 2 =0.0597, 939 F 2 values, 60 variables; Y5Cu5Mg13 – orthorhombic, Cmcm, oS92, a =0.40973(2), b =1.92794(8), c =2.57907(11)nm, Z =4, wR 2 =0.1134, 1208 F 2 values, 75 variables; Y5Cu5Mg16 – orthorhombic, Cmcm, oS104, a =0.41360(8), b =1.9239(4), c =2.9086(6)nm, Z =4, wR 2 =0.0760, 1383 F 2 values, 84 variables. YCuMg4 crystallizes in the TbCuMg4 structure type (Cmmm, oS48, a =1.35754(4), b =2.03153(6), c =0.39060(1)nm, Z =8, wR 2 =0.0401, 661 F 2 values, 45 variables). The crystal chemistry of these two-layer structures is comparatively discussed. Majority of novel compounds were characterized as members of inhomogeneous 2D intergrowth structure series of R5M5X5, X4 (Mg4) and empty Mg octahedra building blocks of general formula R5k M5k X5k +4l + m . The common pentagonal prism derivative structural fragments around the most electropositive yttrium atoms were outlined in all these intermetallics. [Copyright &y& Elsevier]

Adjacent silicon atoms are located in the centre of a 12-verticles polyhedron (Figure 2), but it consists of both europium and silicon, unlike a polyhedron around the Si-Si pairs in Eu SB 5 sb Si SB 3 sb . From the COHP data, it can be concluded that the strongest interactions occur between Si-Si atoms -iCOHP = 1.904 eV (for EuSi) and -iCOHP = 1.927 eV (for Eu SB 5 sb Si SB 3 sb ). 3 Results and discussion 3.1 Crystal structure of Eu 5 Si 3 and EuSi The crystallographic data and details of the data collection from the single crystal of Eu SB 5 sb Si SB 3 sb silicide are listed in Table 1. Keywords: crystal structure; electrochemistry; intermetallics; rare earth silicide; X-ray diffraction EN crystal structure electrochemistry intermetallics rare earth silicide X-ray diffraction 99 109 11 03/11/22 20220201 NES 220201 1 Introduction Generally, the construction of an isothermal section of a multicomponent system gives us knowledge about the possible formation of complex compounds. [Extracted from the article]

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). [ABSTRACT FROM AUTHOR]

The electrochemical hydrogenation, structure and thermal stability of LaNi 4·6 Zn 0.4- x Li x (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 LaNi 4·6 Zn 0.4- x Li x intermetallics are solid solutions on the basis LaNi 5 compound with hexagonal CaCu 5 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) Å, c = 3.9952 (8) Å). The LaNi 4·6 Zn 0.4- x Li x 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 LaNi 4·6 Zn 0.4- x Li x intermetallics compared to the reference compound (LaNi 5). The electrochemical measurements show that LaNi 4·6 Zn 0.4- x Li x intermetallic compounds absorb hydrogen, and the highest effectiveness of hydrogen absorption shows LaNi 4·6 Zn 0·2 Li 0.2 compound with orthorhombic structure. The DSC/TG results indicate greater thermal stability of compounds doped by Zn (LaNi 4·6 Zn 0.4) and Zn/Li (LaNi 4·6 Zn 0·2 Li 0.2) in compare to LaNi 5. Image 1 • The LaNi 4.6 Zn 0.4- x Li x (x £ 0.2) solid solution phases were produced. • In the LaNi 4.6 Zn 0.4- x Li x with the increase of x the hexagonal cell is transformed into orthorhombic structure. • The LaNi 4.6 Zn 0.4- x Li x intermetallics effectively passivate in 6 M KOH over a wide potential range. • The highest effectiveness of hydrogen absorption shows LaNi 4.6 Zn 0.2 Li 0.2 sample with orthorhombic structure. [ABSTRACT FROM AUTHOR]

The equiatomic germanide LaNiGe was synthesized from the elements by arc‐melting and subsequent annealing at 1173 K for 14 days. Its non‐centrosymmetric LaPtSi type structure was refined from single‐crystal X‐ray diffractometer data: I41md, a = 420.80(6), c = 1440.3(3) pm, wR = 0.0477, 284 F2 values and 14 variables. The nickel and germanium atoms build up a three‐dimensional [NiGe]δ– polyanionic network (2 × 241 and 1 × 242 pm Ni–Ge) in which the lanthanum atoms fill cavities with coordination number 12. This picture of chemical bonding is supported by an evaluation of the electron localization function. Physical properties of LaNiGe were studied by means of magnetic susceptibility, magnetization, specific heat and electrical resistivity measurements. The compound was found to be a Pauli paramagnet with a molar magnetic susceptibility of about χ = 1.6 × 10–4 emu·mol–1·Oe–1. The temperature dependence of the electrical resistivity shows Bloch‐Grüneissen‐Mott behavior indicating the metallic character of LaNiGe, which is in full agreement with the results of electronic structure and density of states calculations. No superconducting transition was observed in the temperature regime down to 1.72 K. [ABSTRACT FROM AUTHOR]

The new ternary compound La3Ni4Al2 has been synthesized and the crystal structure has been studied by X-ray single crystal diffraction. La3Ni4Al2 is the first aluminide, crystallizing in the La3Ni4Ga2-type. The crystal structure of La3Ni4Al2 consists of La-layers and hetero-atomic Ni/Al layers, sequentially alternating along the a axis (pseudo-hexagonal c axis). According to electronic structure calculations using the tight-binding linear muffin-tin orbital method in the atomic-sphere approximation (TB-LMTO-ASA), strong Al–Ni interactions have been established. The coordination polyhedra for the Al atoms are cuboctahedra, whereas the bicapped square prism and bicapped square antiprism are typical for nickel atoms. The lanthanum atoms are enclosed in pseudo Frank–Kasper polyhedra. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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, P62m), 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. [ABSTRACT FROM AUTHOR]

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 carbonnanotube. This system was tested in Swagelok-type cells. The cells comprised a system (functionalized CNT withsalts containing S and P atoms) with a working electrode, microfi ber separators soaked with electrolyte solution,and a lithium foil counter/reference (commercial LiCoO2) electrode. The electrolyte solution was 1 M LiPF6 inpropylene carbonate. Using standard techniques (cyclic voltammetry/chronopotentiometry), galvanostatic cyclingwas performed on the cells at room temperature with a CH Instruments Model 600E potentiostat/galvanostatelectrochemical measurements. Methods of functionalization CNT were compared in terms of the electrochemicalproperties of the studied systems. In all systems, the process of charge/discharge was observed. [ABSTRACT FROM AUTHOR]

In the solid state, the structure of the title compound, C10H8O2, is stabilized by both van der Waals interactions and O—H⋯O intermolecular hydrogen bonds with O⋯O distances of 2.714 (3) and 2.831 (4) Å. [ABSTRACT FROM AUTHOR]

The ZrSn intermetallic compound has been studied as a possible anode material for lithium- and magnesium-ion batteries. The ZrSnLi electrodes provide a reversible specific capacity of 160-140 mAh g, whereas ZrSnMg electrodes yield a slightly lower capacity of 110-95 mAh g. The lithiation and magnesiation of ZrSn 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. [ABSTRACT FROM AUTHOR]

The title compounds are synthesized from the elements (Ta crucible, 670 K, 2 d followed by annealing at 1070 K for 6 h) and characterized by single crystal XRD and TB-LMTO-ASA computations. [ABSTRACT FROM AUTHOR]

Abstract: The remarkably broad homogeneity range of the NaTl-type Zintl phase in the ternary phase diagram Li–In–Ag at room temperature was determined by structure evaluation using X-ray powder diffraction. The colours of the investigated Zintl phases correlate with the valence electron concentration (VEC) as already established for the quasibinary cut Li0.5(In x Ag1− x )0.5 with , i.e. with decreasing VECs the colour changes from grey over reddish to bright yellow. All compounds in the new quasibinary cut Li x (In0.5Ag0.5)1− x with appear free from vacancies in the Li-sublattice, even for Li-deficient compositions. The partial occupation of Li-sites by excess Ag and In instead is in full agreement with the behaviour of the binary NaTl-type Zintl phases Li x Zn1− x and Li x Cd1− x () with a low VEC about 1.5. [Copyright &y& Elsevier]

Dietary fiber can be obtained by dextrinization, which occurs while heating starch in the presence of acids. During dextrinization, depolymerization, transglycosylation, and repolymerization occur, leading to structural changes responsible for increasing resistance to starch enzymatic digestion. The conventional dextrinization time can be decreased by using microwave-assisted heating. The main objective of this study was to obtain dietary fiber from acidified potato starch using continuous and discontinuous microwave-assisted heating and to investigate the structure and physicochemical properties of the resulting dextrins. Dextrins were characterized by water solubility, dextrose equivalent, and color parameters (L* a* b*). Total dietary fiber content was measured according to the AOAC 2009.01 method. Structural and morphological changes were determined by means of SEM, XRD, DSC, and GC-MS analyses. Microwave-assisted dextrinization of potato starch led to light yellow to brownish products with increased solubility in water and diminished crystallinity and gelatinization enthalpy. Dextrinization products contained glycosidic linkages and branched residues not present in native starch, indicative of its conversion into dietary fiber. Thus, microwave-assisted heating can induce structural changes in potato starch, originating products with a high level of dietary fiber content. [ABSTRACT FROM AUTHOR]

In the title compound, C19H20N4, the dihedral angles formed by the planes of the triazine ring and the two phenyl substituents are 51.54 (1) and 49.27 (1)°. The phenyl rings form a dihedral angle of 80.81 (1)°. All bond lengths and angles are normal. The structure is stabilized by van der Waals interactions. [ABSTRACT FROM AUTHOR]

Erbium dinickel disilicide, ErNi2Si2, crystallizes in the tetra­gonal ThCr2Si2 structure type, which is an ordered superstucture of the BaAl4 type. The coordination numbers are 22 for Er (2a site), 12 for Ni (4d site), and 9 for Si (4e site). [ABSTRACT FROM AUTHOR]

The article presents information on the structure of the organic compound, 1-(N,N-Diethylamino)-2,3-diphenylcyclopropenylium tetrafluoroborate. The cyclopropenylium ion is a Hückel aromatic cation. It consists of an aminodiphenylcyclopropenylium cation and a tetrafluoroborate anion. C-H⋯F hydrogen bonds stabilizes the crystal packing. The F atoms of the anion revealed high displacement parameters, and the plane of the cyclopropene ring makes angles of 12.14 (13) and 35.78 (14)°, respectively, with the C8-C13 and C14-C19 phenyl rings.

The ternary germanide Mg 5.57 Ni 16 Ge 7.43 (cubic, space group Fm-3m, cF116) belongs to the structural family based on the Th 6 Mn 23 -type. The Ge1 and Ge2 atoms fully occupy the 4a (m-3m symmetry) and 24d (m.mm) sites, respectively. The Ni1 and Ni2 atoms both fully occupy two 32f sites (.3m symmetry). The Mg/Ge statistical mixture occupies the 24e site with 4m.m symmetry. The structure of the title compound contains a three-core-shell cluster. At (0,0,0), there is a Ge1 atom which is surrounded by eight Ni atoms at the vertices of a cube and consequently six Mg atoms at the vertices of an octahedron. These surrounded eight Ni and six Mg atoms form a [Ge1Ni 8 (Mg/Ge) 6 ] rhombic dodecahedron with a coordination number of 14. The [GeNi 8 (Mg/Ge) 6 ] rhombic dodecahedron is encapsulated within the [Ni 24 ] rhombicuboctahedron, which is again encapsulated within an [Ni 32 (Mg/Ge) 24 ] pentacontatetrahedron; thus, the three-core-shell cluster [GeNi 8 (Mg/Ge) 6 @Ni 24 @Ni 32 (Mg/Ge) 24 ] results. The pentacontatetrahedron is a new representative of Pavlyuk's polyhedra group based on pentagonal, tetragonal and trigonal faces. The dominance of the metallic type of bonding between atoms in the Mg 5.57 Ni 16 Ge 7.43 structure is confirmed by the results of the electronic structure calculations. The hydrogen sorption capacity of this intermetallic at 570 K reaches 0.70 wt% H 2 .

The ternary magnesium/lithium boride, Mg x Li 3 -  x B 48 -  y ( x = 1.11, y = 0.40, idealized formula MgLi 2 B 48 ), crystallizes as its own structure type in P 4 3 2 1 2, which is closely related to the structural family comprising α-AlB 12 , Be 0.7 Al 1.1 B 22 and tetra-gonal β-boron. The asymmetric unit of title structure contains two statistical mixtures Mg/Li in Wyckoff sites 8 b with relative occupancies Mg:Li = 0.495 (9):0.505 (9) and 4 a with Mg:Li = 0.097 (8):0.903 (8). The boron atoms occupy 23 8 b sites and two 4 a sites. One of the latter sites has a partial occupancy factor of 0.61 (2). Both unique Mg/Li atoms adopt a twelvefold coordination environment in the form of truncated tetra-hedra (Laves polyhedra). These polyhedra are connected by triangular faces to four [B 12 ] icosa-hedra. The boron atoms exhibit four kinds of polyhedra, namely penta-gonal pyramid (coordination number CN = 6), distorted tetra-gonal pyramid (CN = 5), bicapped hexa-gon (CN = 8) and gyrobifastigium (CN = 8). At the gas hydrogenation of MgLi 2 B 48 alloy, formation of the eutectic composite hydride LiBH 4 +Mg(BH 4 ) 2 and amorphous boron is observed. In the temperature range 543-623 K, the hydride eutectics decompose, forming MgH 2 , LiH, MgB 4 , B and H 2 ., (© Pavlyuk et al. 2024.)

Crystal structures of MgCoGa, Mg 0.74 CoGa 0.52 and Mg 0.49 CoGa 0.15 phases from the Mg-Co-Ga system were investigated using single-crystal diffraction. These structures belong to the family of so-called Laves phases. Hexagonal MgCoGa crystallizes as a disordered phase within the MgZn 2 structure type. The orthorhombic structure of Mg 0.74 CoGa 0.52 is a distortion variant of MgZn 2 and URe 2 structure type, and the structural relation is demonstrated in terms of a Bärnighausen formalism group-subgroup transformation scheme. The structure of trigonal phase Mg 0.49 CoGa 0.15 is strongly disordered, as is shown by the presence of adjacent atomic sites which cannot be occupied simultaneously. In Mg 0.49 CoGa 0.15 , two subcells (A and B) were obtained in a ratio of 9:1. Subcell A is closely related to MgZn 2 -type.

The ternary Tb 2-x Nd x Zn 17-y Ni y (x = 0.5, y = 4.83) disordered phase belongs to the structural family based on the rhombohedral Th 2 Zn 17 structure type. The structure is maximally disordered since all the sites are occupied by statistical mixtures of atoms. The Tb/Nd mixture of atoms occupies the 6c site (site symmetry 3m). The statistical mixtures Ni/Zn consisting of more Ni atoms are located in the 6c and 9d (symmetry .2/m) sites. In the following 18f (site symmetry .2) and 18h (site symmetry .m) sites are located Zn/Ni statistical mixtures which consist of more Zn atoms. Zn/Ni atoms form three-dimensional networks with hexagonal channels that fill statistical mixtures of Tb/Nd and Ni/Zn. The Tb 2-x Nd x Zn 17-y Ni y compound belongs to the family of intermetallic phases capable of absorbing hydrogen. In the structure, there are three types of voids, namely, 9e (site symmetry .2/m), 3b (site symmetry -3m) and 36i (site symmetry 1), in which hydrogen can be inserted, and the maximum total absorption capacity can reach 1.21 wt% H 2 . Electrochemical hydrogenation shows that the phase absorbs 1.03% of H 2 , which indicates partial filling of the voids with H atoms.

Modifying the surface of nanomaterials, such as carbon nanotubes, by introducing heteroatoms or larger functional groups into the structure causes a change in chemical properties-manifested in the increase in reactivity as well as a change in conductivity. This paper presents the new selenium derivatives obtained by a covalent functionalization of brominated multi-walled carbon nanotubes (MWCNTs). The synthesis was carried out in mild conditions (3 days at room temperature), and was additionally assisted with ultrasound. After a two-stage purification, the obtained products were identified and characterized by the following methods: scanning and transmission electron microscopy imaging (SEM and TEM), energy dispersive X-ray microanalysis (EDX), X-ray photoelectron spectroscopy (XPS), Raman and nuclear magnetic resonance (NMR), and X-ray diffraction (XRD). In the selenium derivatives of carbon nanotubes, the content of selenium and phosphorus reached 14 and 4.2 wt%, respectively.