Complex Open-Framework Germanate Built by 8‑Coordinated Ge₁₀ Clusters

A novel open-framework germanate |(C₅H₁₄­N₂)₂­(C₅H₁₂­N₂)_0.5(H₂O)_2.5|[Ge_12.5O₂₆(OH)₂] with three-dimensional 10- and 11-ring channels, denoted as SU-67, has been synthesized under hydrothermal conditions using 2-methylpiperazine (MPP) as the structure-directing agent (SDA). The synthesis is intimately related to that of JLG-5, a tubular germanate built from Ge₇ clusters. The influences of synthesis parameters are discussed. A strong influence of the hydrofluoric acid quantity on the resulting cluster building units can be concluded. The framework of SU-67 is based on an elaborate topological pattern of connected Ge₁₀ clusters forming intersecting 10- and 11-ring channels and has a low framework density (12.4 Ge atoms per 1000 ų). We have discovered that the topology of SU-67 is a new 8-connected <b>nce-8-</b><i><b>I</b></i><b>4</b>_<b>1</b><b>/</b><i><b>acd</b></i> net. Strong hydrogen bonding among the organic SDAs, water molecules, and Ge₁₀ clusters resulted in helical networks in SU-67

Complex Open-Framework Germanate Built by 8‑Coordinated Ge₁₀ Clusters

A novel open-framework germanate |(C₅H₁₄­N₂)₂­(C₅H₁₂­N₂)_0.5(H₂O)_2.5|[Ge_12.5O₂₆(OH)₂] with three-dimensional 10- and 11-ring channels, denoted as SU-67, has been synthesized under hydrothermal conditions using 2-methylpiperazine (MPP) as the structure-directing agent (SDA). The synthesis is intimately related to that of JLG-5, a tubular germanate built from Ge₇ clusters. The influences of synthesis parameters are discussed. A strong influence of the hydrofluoric acid quantity on the resulting cluster building units can be concluded. The framework of SU-67 is based on an elaborate topological pattern of connected Ge₁₀ clusters forming intersecting 10- and 11-ring channels and has a low framework density (12.4 Ge atoms per 1000 ų). We have discovered that the topology of SU-67 is a new 8-connected <b>nce-8-</b><i><b>I</b></i><b>4</b>_<b>1</b><b>/</b><i><b>acd</b></i> net. Strong hydrogen bonding among the organic SDAs, water molecules, and Ge₁₀ clusters resulted in helical networks in SU-67

Two Open-Framework Germanates with Nickel Complexes Incorporated into the Framework

Two open-framework germanates, SUT-1 and SUT-2, have been synthesized under hydrothermal conditions using ethylenediamine (en, H(2)NCH(2)CH(2)NH(2)) as templates and Ni(NO(3))(2)·6H(2)O as the transition-metal source. Their frameworks are built with Ge(10) clusters and [Ni(en)(2)](2+) complexes. In both structures, Ge(10) clusters form square nets in the a-c plane, while the [Ni(en)(2)](2+) complexes bridge the square nets via Ni-O-Ge bonds to form 3D networks. They present the first examples to incorporate Ni(2+) complexes into the germanate frameworks. In SUT-2, additional linkages by Ge(2)O(7) clusters between the square nets generate a new type of topology.

SU-62: Synthesis and Structure Investigation of a Germanate with a Novel Three-Dimensional Net and Interconnected 10- and 14-Ring Channels

A novel 3D open-framework germanate, |N₂C₄H₁₄|₄ [Ge₂₀O₄₁(OH)₆]·3H₂O (SU-62), was prepared from hydrothermal synthesis using 1,4-diaminobutane as the organic structure directing agent (SDA). The crystal structure was solved by single crystal X-ray diffraction. The framework is built from Ge₁₀(O,OH)₂₇ (Ge₁₀) secondary building units and exhibits an irregular three-dimensional channel system encircled by 10- and 14-rings. The framework of SU-62 has an underlying topology that follows a novel five-coordinated <b>svh-5-</b><i><b>I</b></i><b>4</b>_<b>1</b><b>/</b><i><b>amd</b></i> net, while the pores follow the <b>tsi</b> net. The thermal behavior of SU-62 was studied by thermogravimetric (TG) analysis and <i>in situ</i> X-ray diffraction (XRPD). Crystallographic data: orthorhombic, space group <i>Fdd</i>2, unit cell parameters <i>a</i> = 15.297(3) Å, <i>b</i> = 53.58(1) Å, <i>c</i> = 14.422(3) Å, <i>V</i> = 11821(4) ų, <i>Z</i> = 8

Computer-Aided Modeling of Aluminophosphate Zeolites As Packings of Building Units

New building schemes of aluminophosphate molecular sieves from packing units (PUs) are proposed. We have investigated 61 framework types discovered in zeolite-like aluminophosphates and have identified important PU combinations using a recently implemented computational algorithm of the TOPOS package. All PUs whose packing completely determines the overall topology of the aluminophosphate framework were described and catalogued. We have enumerated 235 building models for the aluminophosphates belonging to 61 zeolite framework types, from ring- or cage-like PU clusters. It is indicated that PUs can be considered as precursor species in the zeolite synthesis processes

Electronic and Magnetic Properties of Infinite 1D Chains of Paddlewheel Carboxylates M₂(COOR)₄ (M = Mo, W, Ru, Rh, Ir, Cu)

Dinuclear complexes of transition metals bridged by four carboxylate-groups are examples of stable atomic configurations serving as fundamental building blocks of catalysts and prototypical molecular electronic devices. The electronic structure and magnetic properties of many molecular tetracarboxylate complexes were meticulously studied; however, the properties of the one-dimensional (1D) polymeric chain of associated tetracarboxylates have so far evaded much attention. Using periodic density-functional theory calculations, we analyze the electronic structure of condensed tetracarboxylates Mo­(II), W­(II), Ru­(II), Rh­(II), Ir­(II), and Cu­(II). The relationship between crystal structure of the polymerized tetracarboxylates and the electronic properties of the metal–metal bond in the M₂⁴⁺ core is studied. The electronic effects emanating from the association of dinuclear transition metal tetracarboxylates are important for designing molecular electronic devices. In this study, its influence on both direct and indirect metal–metal interactions, and the electronic structure, in particular transport properties, is discussed

CCDC 856859: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures

CCDC 856858: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures

Experimental Studies of Microwave Tubes with Components of Electron&ndash;Optical and Electrodynamic Systems Implemented Using Novel 3D Additive Technology

Novel additive technology of the Chemical Metallization of Photopolymer-based Structures (CMPS) is under active elaboration currently at the IAP RAS (Nizhny Novgorod). The use of this technology has made it possible to implement components of electron&ndash;optical and electrodynamic systems for high-power microwave vacuum tubes, such as a gyrotron and a relativistic Cherenkov maser, the design and experimental studies of which are described in this paper. Within the framework of the gyrotron developments, we carried out a simulation of the distribution of the heat load on the collector of high-power technological gyrotron taking into account secondary emission. The prospect of a significant reduction in the maximum power density of the deposited electron beam was shown. The experimental study of the gyrotron collector module manufactured using CMPS technology demonstrated high potential for its further implementation. Recent results of theoretical and experimental studies of a spatially extended Ka-band Cherenkov maser are presented. In this oscillator, the 2D-periodical slow-wave structure made by the proposed technology was applied and a narrow-band generation regime was observed with a sub-GW power level. The design and simulations of a novel selective electrodynamic system for a high-harmonic gyrotron with the planned application of the CMPS technology are discussed