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71.
Huang YX Hochrein O Zahn D Prots Y Borrmann H Kniep R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(6):1737-1745
The templated microporous compounds [H2(Templ.)][MnII{B2P3O12(OH)}], [templates: 1,3-diaminopropane, C3H10N2 (DAP); piperazine, C4H10N2 (PIP); 1,4-diazacyclo[2.2.2]octane, C6H12N2 (DABCO)] were prepared under mild hydrothermal conditions. The crystal structures (H2DAP-Mn: Pmc2(1) (no. 26), a=1259.43(5), b=949.86(5), c=1135.92(5) pm, Z=4; H2PIP-Mn: Ima2 (no. 46), a=1257.9(1), b=948.69(8), c=1158.19(8) pm, Z=4; H2DABCO-H2PIP-Mn: Ima2 (no. 46), a=1262.90(7), b=961.05(5), c=1151.42(7) pm, Z=4) are characterized by identical framework connectivities [MnII{B2P3O12(OH)}]2-, but vary in shapes (diameters) of the structural channels depending on the shapes of the templating molecule ions. The situation clearly reflects the directing effect of true templates during endotemplating reactions. The experimental results (preparation, chemical analyses, and X-ray refinements) are supported by detailed ab initio calculations (structure optimizations). 相似文献
72.
CsSc[B2P3O11(OH)3] was obtained by hydrothermal synthesis and represents the first alkali-metal scandium borophosphate containing boron with coordination numbers 3 and 4. The crystal structure was determined from single-crystal X-ray data: orthorhombic, space group Pnna (No. 52), a=13.0529(15) A, b=18.3403(17) A, c=10.3838(12) A, Z=8. The crystal structure contains the oligomeric unit [B2P3O11(OH)3]4- in which a central borate tetrahedron is open-branched by two (OH)PO3 tetrahedra and cyclobranched by one PO4 tetrahedron and a trigonal-planar (OH)BO2 by sharing common apexes. The borophosphate oligomers together with the ScO6 octahedra are condensed to form layers. Simultaneous difference thermal analysis and thermogravimetry revealed the stepwise decomposition of the compound in the temperature range between 333 and 973 K. Partly dehydrated samples do not show any substantial rehydration behavior. The crystal structure of CsSc[B2P3O11(OH)3] is discussed in connection with structural motifs of related borates and borophosphates. 相似文献
73.
Strojek W Fehse CM Eckert H Ewald B Kniep R 《Solid state nuclear magnetic resonance》2007,32(3):89-98
A comprehensive solid-state NMR investigation on crystalline Na(5)B(2)P(3)O(13) is presented. Triple-quantum magic angle spinning (TQMAS) and rotational echo double resonance (REDOR) studies are used for accurate determinations of the (11)B, (23)Na and (31)P interaction parameters. Based on these results and complementary quantum mechanical calculations, plausible site assignments can be derived. Generally, the results show that detailed, quantitative information about structures in borophosphate compounds can be obtained by investigating both the local site environments characterized by chemical shift and quadrupolar interaction parameters and the correlated dipolar interactions to atoms in the second coordination sphere. 相似文献
74.
NaSc3[HPO3]2[HPO2(OH)]6 was prepared by use of a phosphorus acid flux route. The crystal structure was determined from single‐crystal X‐ray diffraction data: triclinic, space group P$\bar{1}$ (No. 2), a = 7.4507(11) Å, b = 9.6253(17) Å, c = 9.6141(16) Å, α = 115.798(4)°, β = 101.395(4)°, γ = 101.136(3)°, V = 577.29(16) Å3 and Z = 1. The crystal structure of NaSc3[HPO3]2[HPO2(OH)]6 contains two kinds of phosphate(III) groups: HPO32– and HPO2(OH)–. Phosphate(III)‐tetrahedra, NaO6 and ScO6 octahedra together form a (3,6)‐connected net. During heating hydrogen and water are released and Sc[PO3]3 is formed as the main crystalline decomposition product. 相似文献
75.
76.
F Kniep L Rout SM Walter HK Bensch SH Jungbauer E Herdtweck SM Huber 《Chemical communications (Cambridge, England)》2012,48(74):9299-9301
Bi- and tridentate polycationic halogen bond donors based on 5-iodo-1,2,3-triazolium groups have been synthesized by 1,3-dipolar cycloaddition reactions. These halogen-based Lewis acids have been evaluated as activators in a halide-abstraction benchmark reaction. 相似文献
77.
Peter Höhn Dr. Stefan Hoffmann Dr. Jens Hunger Dr. Stefano Leoni Dr. Fabian Nitsche Dipl.‐Chem. Walter Schnelle Dr. Rüdiger Kniep Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3419-3425
A new page in the phase book : The metastable nitride β‐Ca3N2, the synthesis, crystal structure (see picture), and physical properties of which are reported, is an isotype of corundum (α‐Al2O3). Vacancies in the crystal structure of β‐Ca3N2 are discussed by using full‐potential local orbital methods and taking into account both the physical properties and the density of states.
78.
Prashanth W. Menezes Stefan Hoffmann Yurii Prots Rüdiger Kniep Prof. Dr. 《无机化学与普通化学杂志》2009,635(1):33-35
KSc(HPO4)2 was obtained by hydrothermal synthesis. The crystal structure was determined from single‐crystal X‐ray data: orthorhombic, space group Pnma (No. 62), a = 14.5095(10), b = 5.4260(4), c = 8.4882(5) Å, V = 668.26(8) Å3 and Z = 4. The crystal structure of KSc(HPO4)2 represents a new structure type containing twelve‐ and four‐membered rings forming channels along [010] built of alternating ScO6 octahedra and HPO42? groups. Potassium ions reside within the twelve membered ring channels. 相似文献
79.