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Alloys from the region of existence of the solid solution TbCo4.5SixLi0.5-x were synthesized by arc melting. Quantitative and qualitative composition of alloys and powders of electrode materials was determined by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The Tb/Co/Si ratio in the samples was confirmed by X-ray fluorescence spectroscopy. The change in cell parameters within the solid solution existence was established by the results of X-ray powder diffraction (TbCo4.5SixLi0.5-x, x = 0.1–0.4: a = 4.9518(5) – 4.9324(3), c = 3.9727(4) – 3.9746(3) Å). The crystal structure of the solid solution was determined by the Rietveld method (CaCu5 structure type, space group P6/mmm). Cobalt atoms are partially replaced by silicon and lithium only in 2c position. The ability of alloys to reversibly absorb hydrogen was studied by the method of electrochemical hydrogenation. Under experimental conditions the amount of deintercalated hydrogen was about 0.19 H/f.u. The change in cell parameters after hydrogenation (volume increases from 83.74(1) to 85.54(6) Å3) and the stability of the electrode in the electrolyte solution was further confirmed by X-ray phase analysis. Measurements of the electrical resistivity of the samples indicated a decrease of resistivity value with a slight increase in the amount of alkali metal in samples.

The crystal structure of La2Mg17-xSnx solid solution was determined by single crystal X-ray diffraction for the first time. This phase crystallizes in hexagonal symmetry with space group P63/mmc (a = 10.3911(3), c = 10.2702(3) Å, V = 960.36(6) Å3, R1 = 0.0180, wR2 = 0.0443 for the composition La3.65Mg30Sn1.10) and is related to the structure of CeMg10.3 and Th2Ni17-types which are derivative from the CaCu5-type. A series of isotypical solid solutions La2Mg17-xMx (M = Ni, Sn, Sb, x ~0.8) was synthesized and studied by X-ray powder diffraction, energy dispersive X-ray spectroscopy and fluorescent X-ray spectroscopy. All solid solutions crystallize with the structure related to the Th2Ni17-type. The electrochemical hydrogenation confirmed the similar electrochemical behavior of all studied alloys. The amount of deintercalated hydrogen depends on the physical and chemical characteristics of doping elements and increases in the sequence Sn < Mg < Sb < Ni. The most geometrically advantageous sites are octahedral voids 6h of the initial structure, thus a coordination polyhedron for H-atom is an octahedron [HLa2(Mg,M)4].

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.

This article highlights some of the results of the scientific work conducted under the direction of the Institute of Architecture and Design of the National University “Lviv Polytechnic” together with the Department of Fine Arts and Design of Ternopil National Pedagogical University, Kremenets Regional Humanities and Pedagogics Academy, Lesia Ukrainka Eastern European National University, Department of Fine Arts. Scientists are exploring sacred arts in Western Ukraine as one of the highest achievements in the work of Ukrainian architects. In particular, the article is about the Ternopil region. The aim of the article is to cover the work of architects of the Ternopil region, correlation in their creativity of architecture and painting; the introduction into the scientific circulation of data on some temples - architectural monuments and modern churches. The territory of Western Ukraine occupies a special place in the cultural and spiritual space of the state. It is located at the crossroads of European roads, has long been noted for its multinational character and wealth of faiths. Temples of different denominations are the decoration of cities and villages and enrich their architectural landscape, and in terms of potential and value of architectural heritage, it is one of the richest regions of Ukraine. One of the spiritual symbols of the city of Ternopil is a temple built in the eighteenth century - a monument of late European Baroque architecture. The building was many times on the verge of destruction; it was burned and destroyed by wars and the communist regime, but with the declaration of independence of Ukraine the shrine was revived. Modern paintings, sculptural groups, stained glass windows and other works of sacred art have transformed the sanctuary into a city beauty, attracting visitors with its grandeur and splendor. Scientists do not often turn to the creative personality of architects. Among the renowned architects of Ukraine, who have designed projects for more than 200 temple complexes, is Ternopil artist Mykhaylo Netrybyak. He combines the work of the architect with the work of the teacher, and the creative nature of the artist is reflected in the paintings. The famous painter of Ternopil with professional architectural education is Mykhaylo Kuziv, who also combines artistic work with pedagogical activity. His works are known far beyond Ukraine and are exhibited in state and public institutions, in private collections of Ukraine and in many countries of the world. Thus, as a result of the research, the data on some contemporary architects and artists of Ternopil region were put into scientific circulation; their role in the process of revival of temple construction of Ukraine is defined; it describes some of the temples – architectural monuments and modern architectural buildings.

Synthesis, study of the phase, structural and electrochemical characteristics of the alloys from homogeneity range of the continious series of solid solutions Tb 2 Ni 17- x Co x (0 ≤ x ≤ 17) was carried out in the prototype of NiMH battery for the purpose of search of new materials for modern electrical energy sources. The samples for investigation were synthesized by arc melting of pure components under an argon atmosphere with further annealing at 600 oC for one month in evacuated silica ampules. X-ray powder diffraction, scanning electron microscopy, X-ray fluorescent and energy dispersive X-ray spectroscopy were used to examine the alloys before and after electrochemical studies. The process of electrochemical hydrogenation of the samples was carried out in two-electrode “Swagelok-cell” prototype of NiMH battery. Studied alloys were used as anode materials (during discharging of the batteries). A mixture of Ni(OH) 2 and graphite served as cathode material (during discharging of the batteries). The anode and cathode materials were soaked by 6 M solution of KOH as electrolite and separated by pressed cellulose to avoid contacts between them. During charging we obtained the hydride of inclusion on the basis of Tb 2 Ni 17- x Co x phases. The process of hydrogenation is characterized by one stage, namely the inclusion of H-atoms into vacant tetrahedral and octahedral voids. At the small hydrogen concentration its atoms occupy the octahedral voids (6 h ) formed by two Tb atoms and four (Ni, Co) atoms. As electrode materials, the studied phases are relatively stable in the electrolyte solution. Increasing of the cobalt content improves the electrode capacity, but decreases the corrosion stability of the electrodes to the action of the electrolyte that is confirmed by the decreasing of crystallinity, passivation of the surfaces and changing of quantitative compositions of the samples. The amount of mobile hydrogen under the same conditions (during discharge) is the following: 1.53 H/f.u. for Tb 2 Ni 17 , 1.83 H/f.u. for Tb 2 Ni 12 . 2 Co 4 . 8 and 2.08 H/f.u. for Tb 2 Ni 6 . 5 Co 10 . 5 . The specific capacity does not exceed 60 mA∙h/g. The electrochemical processes in all cases led to changing of the surface morphology, reducing of the grains size. Significant amorphization was observed for electrodes with higher content of Co. Keywords : intermetallic compound, continious series of solid solutions, electrochemical hydrogenation, nickel metal hydride batteries.

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 Li

New ternary dodeca­lithium dodeca­copper tetra­deca­aluminium, Li12Cu12.60Al14.37 (trigonal, R\overline{3}m, hR39), crystallizes as a new structure type and belongs to the structural family that derives from binary Laves phases. The Li atoms are enclosed in 15- and 16-vertex and the Al3 atom in 14-vertex pseudo-Frank–Kasper polyhedra. The polyhedra around the statistical mixtures of (Cu,Al)1 and (Al,Cu)2 are distorted icosa­hedra. The electronic structure was calculated by the TB–LMTO–ASA (tight-binding linear muffin-tin orbital atomic spheres approximation) method. The electron localization function, which indicates bond formation, is mostly located at the Al atoms. Thus, Al—Al bonding is much stronger than Li—Al or Cu—Al bonding. This indicates that, besides metallic bonding which is dominant in this compound, weak covalent Al—Al inter­actions also exist.

The ternary compound Li278(In,Ag)154 ≡ Li0.643(In,Ag)0.357 with approximated composition Li278In114Ag40 ≡ Li0.643In0.264Ag0.093 was synthesized from the pure elements in a sealed iron crucible. The crystal structure was determined by single crystal X-ray diffraction (space group F 4 ¯ 3 m , a = 20.089(2) A, R1 = 0.0408, 470 F2 values, 38 parameters) and confirmed by X-ray powder diffraction. The (4b)- and (4d)-sites are exclusively occupied by lithium atoms, and the (4a)- and (4c)-sites are occupied by statistical mixtures of (Ag + Li). All sites (4a)–(4d) with local symmetry 4 ¯ 3 m are fully occupied in contrast to the related crystal structures of Li21Si5 and Li17M4 (M = Ge, Sn, Pb). The crystal structure of the compound Li278(In,Ag)154 with approximate composition Li:In:Ag = 278:114:40 represents a new superstructure variant of the bcc W-type and is compared with the similar W-type superstructures of Li21Si5 and Li17M4.

Penta­zirconium copper tribismuth, Zr5CuBi3, crystallizes in the hexa­gonal Hf5CuSn3 structure type. The asymmetric unit contains two Zr sites (site symmetries 3.2 and m2m), one Cu site (site symmetry 3.m) and one Bi site (site symmetry m2m). The environment of the Bi atoms is a tetra­gonal anti­prism with one added atom and a coordination number (CN) of 9. The polyhedron around the Zr1 atom is a defective cubo­octa­hedron with CN = 11. The bicapped hexa­gonal anti­prism (CN = 14) is typical for Zr2 atoms. The Cu atom is enclosed in a eight-vertex polyhedron (octa­hedron with two centered faces). The metallic type of bonding was indicated by an analysis of the inter­atomic distances and electronic structure calculation data.

The new ternary phase penta-terbium lithium tris-tannide, Tb(5)LiSn(3), crystallizes in the hexa-gonal Hf(5)CuSn(3) structure type, which is a 'filled' version of the binary RE(5)Sn(3) phases (Mn(5)Si(3)-type) (RE is rare earth). The asymmetric unit contains two Tb sites (site symmetries 3.2 and m2m), one Li site (site symmetry [Formula: see text].m) and one Sn site (site symmetry m2m). The 14-vertex Frank-Kasper polyhedra are typical for Li and Tb atoms. The environment of the Sn atom is a pseudo-Frank-Kasper polyhedron with a coordination number of 13 for the tin atom. One of the Tb atoms is enclosed in a 17-vertex polyhedron. The metallic type of bonding was indicated by an analysis of the inter-atomic distances.

A phase transition from the cubic CsCl-type structure (Pm-3m space group) into a tetragonal UPb-type structure (I41/amd) is observed for the LiAg binary compound at ambient conditions. The crystal structure of the tetragonal modification of the LiAg binary compound was solved by direct methods in SHELXS on the base of structure factors which were extracted from a powder diffraction pattern and refined by SHELXL and the Rietveld method (a = 3.9605(1), c = 8.2825(2) A, Bragg R-factor = 4.81, Rf-factor = 4.87). Elevated temperatures and/or a small Li-excess versus the equimolar composition favour the cubic structure whereas ambient and lower temperatures and/or a small Li-deficiency stabilize the tetragonal structure. This reconstructive transition is reversible but proceeds slowly.

The new ternary lithium copper aluminide, Li(12)Cu(16+x)Al(26-x) (x = 3.2), dodecalithium nonadecacopper tricosaaluminide, crystallizes in a new structure type with space group P4/mbm. Among nine independent atomic positions, two Al (one of which is statistically disordered with Cu) and three Li atoms have point symmetry m.2m, two statistically disordered Al/Cu atoms are in m.. sites, one Al atom is in a 4/m.. site and one Cu atom occupies a general site. The framework of Li(12)Cu(16+x)Al(26-x) consists of pseudo-Frank-Kasper polyhedra enclosing channels of hexagonal prisms occupied by Li atoms. The crystallochemical peculiarity of this new structure type is discussed in relation to the derivatives from Laves phases (LiCuAl(2) and Li(8)Cu(12+x)Al(6-x)) and to the well known CaCu(5) structure.

The new ternary lithium copper aluminide, Li(12)Cu(16+x)Al(26-x) (x = 3.2), dodecalithium nonadecacopper tricosaaluminide, crystallizes in a new structure type with space group P4/mbm. Among nine independent atomic positions, two Al (one of which is statistically disordered with Cu) and three Li atoms have point symmetry m.2m, two statistically disordered Al/Cu atoms are in m.. sites, one Al atom is in a 4/m.. site and one Cu atom occupies a general site. The framework of Li(12)Cu(16+x)Al(26-x) consists of pseudo-Frank-Kasper polyhedra enclosing channels of hexagonal prisms occupied by Li atoms. The crystallochemical peculiarity of this new structure type is discussed in relation to the derivatives from Laves phases (LiCuAl(2) and Li(8)Cu(12+x)Al(6-x)) and to the well known CaCu(5) structure.

The new ternary lithium copper aluminide Li8Cu12+xAl6−x (x = 1.16) crystallizes in the P63/mmc space group with six independent atom positions of site symmetries \overline{3}m. (Al/Cu mixture), \overline{6}m2 (Li atoms), 3m. (Al/Cu mixture and Li atoms) and .m. (Cu atoms). The compound is a derivative of the K7Cs6 binary structure type and is related to the binary MgZn2 Laves phase and the LiCuAl2, MgCu1.07Al0.93 and Mg(Cu1−xAlx)2 (x = 0.465) ternary Laves phases. The coordination polyhedra of the atoms in this structure are icosa­hedra (Cu atoms), slightly distorted icosa­hedra and bicapped hexa­gonal anti­prisms (Al/Cu statistical mixture), and Frank–Kasper and distorted Frank–Kasper polyhedra (Li atoms). All inter­atomic distances indicate metallic type bonding.

The new ternary lithium copper aluminide Li8Cu12+xAl6−x (x = 1.16) crystallizes in the P63/mmc space group with six independent atom positions of site symmetries \overline{3}m. (Al/Cu mixture), \overline{6}m2 (Li atoms), 3m. (Al/Cu mixture and Li atoms) and .m. (Cu atoms). The compound is a derivative of the K7Cs6 binary structure type and is related to the binary MgZn2 Laves phase and the LiCuAl2, MgCu1.07Al0.93 and Mg(Cu1−xAlx)2 (x = 0.465) ternary Laves phases. The coordination polyhedra of the atoms in this structure are icosa­hedra (Cu atoms), slightly distorted icosa­hedra and bicapped hexa­gonal anti­prisms (Al/Cu statistical mixture), and Frank–Kasper and distorted Frank–Kasper polyhedra (Li atoms). All inter­atomic distances indicate metallic type bonding.

The new terbium (lithium zinc) distannide, TbLi(1-x)Zn(x)Sn(2) (x = 0.2) crystallizes in the ortho-rhom-bic CeNiSi(2) structure type with space group Cmcm and Pearson symbol oS16. Of the four independent 4c atom positions (m2m site symmetry), three are fully occupied by individual atoms (two by Sn and one by Tb atoms) and the fourth is occupied by Li and Zn atoms with a statistical distribution. The Tb coordination polyhedron is a 21-vertex pseudo-Frank-Kasper polyhedron. One Sn atom is enclosed in a tricapped trigonal prism, the second Sn atom is in a cubocta-hedron and the statistically distributed (Li,Zn) site is in a tetra-gonal anti-prism with one added atom. Electronic structure calculations were used for the elucidation of reasons for and the ability of mutual substitution of lithium and transition metals. Positive charge density was observed around the rare earth atom and the Li and Zn atoms, the negative charge density in the proximity of the Sn atoms.