Dimere und polymere Pnictidostannat(IV)-Anionen -Darstellung und Kristallstrukturen von Na2K3[SnP3], Na2Cs3[SnP3] und Na2K3[SnBi3] / Dimeric and Polymeric Pnictidostannate(IV) Anions -Preparation and Crystal Structures of Na2K3[SnP3], Na2Cs3[SnP3] and Na2K3[SnBi3]

1998 ◽  
Vol 53 (4) ◽  
pp. 405-410 ◽  
Author(s):  
Matthias Asbrand ◽  
Brigitte Eisenmann ◽  
Holger Engelhardt ◽  
Ute Rößler

Abstract The metallic lustrous compounds Na2K3[SnP3], Na2Cs3[SnP3], and Na2K3[SnBi3] were prepared from melts of mixtures of the elements. The isotypic compounds Na2K3[SnP3] and Na2Cs3[SnP3] crystallize in the orthorhombic system, space group Cmca (No 64), Z = 8, with lattice constants a = 1996.1 (4)/2047.9(4) pm, b = 669.5(1)/686.5(2) pm, c = 1494.5(2)/1617.8(3) pm. The structure is characterized by dimeric units [Sn2P6] 10- of edge-sharing [SnP4] tetrahe­dra, which are coordinated by the alkali cations. Na2K3[SnBi3] crystallizes in the orthorhombic system, space group Ibca (No 73), Z = 8, with lattice constants a = 718.2(1) pm , b -1692.6(2) pm, c = 2159.5(2) pm. In the anionic partial structure [SnBi4] tetrahedra are connected via common corners to infinite 1∞[SnBi3]5- Zweier single chains. The sodium and potassium cat­ ions separate the chains from each other. Neglecting the distortions caused by covalent bonding and different radii both structure types can be classified as superstructure defect variants of the Li3Bi structure. Different orderings in the occupation of the tetrahedral voids lead to the variants in the anionic assemblies.

1987 ◽  
Vol 42 (11) ◽  
pp. 1309-1312 ◽  
Author(s):  
Robert Becker ◽  
Wolfgang Brockner ◽  
Brigitte Eisenmann

TlSnPS4 crystallizes in the orthorhombic system, space group Pna21 (Nr. 33), Z = 4 with the lattice constants a = 1175.8 (5) pm, b = 890.1 (4) pm, c = 663.3 (4) pm. In the structure are sligthly distorted discrete PS3-4 anions.The far infrared, infrared and Raman spectrum is assigned on the basis of PS3-4 -units with C3v symmetry. According to the DTA data the melting point for TlSnPS4 is 575 ± 5 °C. The title compound is not moisture sensitive and semi-conducting.


1988 ◽  
Vol 43 (10) ◽  
pp. 1219-1223 ◽  
Author(s):  
Johannes Beck

PPh3Au(tolN5tol) is obtained by the reaction of PPh3Au+ClO4- with Tl(tolN5tol). It crystallizes in the monoclinic space group P21/c with the lattice parameters a = 1548.8(5), b = 1070.7(2), c = 1779.1(3) pm, β = 90.33(2)°, Z = 4. In the monomeric complex the gold atom is nearly linearcoordinated by the phosphorus atom of the PPh3 group and nitrogen atom N3 of the pentaazadienido ligand ( N3 - Au - P 178.4°). tolNN(NCH3)NNtol crystallizes in the orthorhombic space group Pccn with the lattice constants a = 2426.7(9), b = 469.3(2), c = 1195.3(4) pm. The unit cell contains four molecules, located on twofold axes. Due to the isolobality of the CH3 and the PPh3Au group, the two structures are closely related. Both contain the typical planar zig-zag chain of five nitrogen atoms with located double bonds N1-N2 and N4 - N5 (from 119.8 to 126.6 pm) and shortened single bonds N2 - N3 and N3 - N4 (132.7 to 140.0 pm).


2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
ElSayed M. Shalaby ◽  
Aisha M. Moustafa ◽  
Adel S. Girgis ◽  
Aida M. ElShaabiny

Three substituted pyridinecarboxylates were synthesized; (I) ethyl 2-bromo-4-4(fluorophenyl)-6-phenyl-3-pyridinecarboxylate, C20H15BrFNO2, (II) ethyl 4-(4-fluorophenyl)-2-(4-morpholinyl)-6-phenyl-3-pyridinecarboxylate, C24H23FN2O3, and (III) ethyl 4-(4-fluorophenyl)-6-phenyl-2-(1-piperidinyl)-3-pyridinecarboxylate, C25H25FN2O2. It was found that compound (I) belongs to the orthorhombic system with space group P212121, compound (II) to the monoclinic system with space group P21/c, and compound (III) to the monoclinic system with space group C2/c. The morpholine ring in (II) and piperidine ring in (III) have the shape of the distorted chair configuration.


2013 ◽  
Vol 69 (9) ◽  
pp. 995-1001 ◽  
Author(s):  
Günther J. Redhammer ◽  
Gerold Tippelt

The crystal structures of three alkali tetragermanatesA2Ge4O9(A= Na, K and Rb) [namely disodium tetragermanate, Na2Ge4O9, dipotassium tetragermanate, K2Ge4O9, and dirubidium tetragermanate, Rb2Ge4O9] are trigonal (space groupP\overline{3}c1). The main building units are a three-membered ring of tetrahedra, oriented within the (001) plane and forming tetrahedral sheets. These sheets are connected to each other by two different regular isolated GeO6octahedraviacorner-sharing to build up a tetrahedral–octahedral framework. The alkali cations are located in cavities within this framework and are sevenfold coordinated. The increasing size of theA-site cation is accommodated by twist deformations of the tetrahedral rings and alterations in the Ge—O—Ge angles. With increasing size of theA-site cation, both the tetrahedral and octahedral sites become more regular, with slightly decreasing 〈Ge—O〉 distances from Na2Ge4O9to Rb2Ge4O9. This goes hand-in-hand with a more uniform distribution of bonds around theA-site cation. All these observations make Rb2Ge4O9the most regular member of thisA2Ge4O9octahedral–tetrahedral framework structure series.


1986 ◽  
Vol 64 (4) ◽  
pp. 816-823 ◽  
Author(s):  
Marie E. Fraser ◽  
Suzanne Fortier ◽  
André Rodrigue ◽  
John W. Bovenkamp

The crystal structures of the 1:2 host:guest complexes of dicyclohexano-18-crown-6 (isomer B) with potassium phenoxide and dicyclohexano-18-crown-6 (isomer A) with sodium phenoxide have been determined. The potassium phenoxide complex crystallizes in space group [Formula: see text] with a = 10.023(2), b = 11.238(2), c = 7.546(2) Å, α = 95.73(2), β = 103.04(2), γ = 92.03(2)°, and Z = 1. The sodium phenoxide complex crystallizes in space group P21/n with a = 19.185(12), b = 13.266(5), c = 13.038(5) Å, β = 96.55(4)°, and Z = 4. Both structures were solved by direct methods and refined by full matrix least-squares calculations to a residual, R, of 0.035. The host conformation as well as the metal cation coordination differ considerably in the two structures. In the potassium phenoxide complex, the two cations are related by symmetry and have, consequently, the same chemical environment. Each potassium is located approximately halfway between the plane formed by the crown ether oxygens and the phenoxide anions and is coordinated to four of the crown oxygens and to two phenoxide oxygens. The oxygens of the crown are found to outline an elliptical cavity and to lie approximately in a plane. In the sodium phenoxide complex, the two sodiums have different crystallographic and chemical environments. One sodium is coordinated to the six hexaether oxygens, with distances ranging from 2.36to2.84 Å, and to one of the phenoxide oxygens. The other sodium is coordinated to only one of the crown oxygens and to three of the phenoxide oxygens. The hexaether adopts a highly irregular conformation.


1988 ◽  
Vol 43 (4) ◽  
pp. 463-466 ◽  
Author(s):  
Gerhard Cordier ◽  
Michael Stelter

AbstractThe compound Sr5Al2Sb6 crystallizes in the orthorhombic system (space group Pnma (No. 62)) with the lattice constants: a = 1212.4(4) pm, b = 1034.1(4) pm, c = 1340.9(5) pm. AlSb4 tetrahedra are connected via common edges and corners to chains. Every second terminal Sb atom of the chain is connected to another Sb atom, such that end-on Sb2 groups and terminal Sb alternate. The compound Ba5In2Sb6 crystallizes in the orthorhombic system (space group Pbam (No. 55)). The lattice constants are: a = 1530.7(6) pm, b = 1335.8(5) pm, c = 478.6(2) pm. In the structure, InSb4 tetrahedra are connected via common corners and Sb2 groups to form double chains. Both compounds are classified as Zintl phases.


1984 ◽  
Vol 39 (6) ◽  
pp. 736-738 ◽  
Author(s):  
Brigitte Eisenmann ◽  
Mehmet Somer

AbstractThe new compound K2SiP2 crystallizes in the orthorhombic system , space group Ibam. The unit cell with the lattice constantsa = 1292.6(6) pm, b - 686.7(4) pm, c - 610.7(4) pmcontains 4 formula units. In the structure SiP4 tetrahedra form chains by sharing common edges. The [(SiP2)2-] strings are isosteric to the SiS2 molecules.


1986 ◽  
Vol 41 (11) ◽  
pp. 1416-1419 ◽  
Author(s):  
Gerhard Cordier ◽  
Herbert Schäfer ◽  
Michael Stelter

Abstract The new compounds Sr3In2P4 and Ca3In2As4 crystallize in the orthorhombic system , space group Pnnm (No. 58), with the following lattice constants:Sr3In2P4: a = 1632.3(6), b = 682.8(3), c = 428.9(2);Ca3In2As4: a = 1621.2(6), b = 659.5(3), c = 430.6(2).In the anionic partial lattice InP4 (InAs4) tetrahedra are connected by common edges and corners and form (InP23-)n ((In As23-)n) strings of alternating four-membered and eight-membered rings.


1998 ◽  
Vol 547 ◽  
Author(s):  
Zhen Chen ◽  
Ru-Ji Wang ◽  
Jing Li

AbstractSolvothermal reactions in ethylenediamine have resulted in two quaternary mercury containing selenoantimonates: RbHgSbSe3 (I) and CsHgSbSe3 (II). Compound I crystallizes in monoclinic system, space group P2l/c (no. 14) with a = 7.758(2)Å, b = 11.234(2)Å, c = 8.849(2) Å, β = 106.60(3)°, V = 739.1(3)Å3, Z = 4. Compound II crystallizes in orthorhombic system, space group Cmcm (no. 63) with a = 4.444(1)Å, b = 15.514(6)Å, c = 11.261(7) Å, V = 776.4(6) Å3, Z = 4. Both compounds are layered materials and their crystal structures are closely related. Both contain layers of 2[HgSbSe3-] separated by alkali-metal cations A+ (Rb, Cs). Diffuse reflectance experiments show that both compounds are semiconductors with estimated band gaps of 1.7 eV for I and 1.6 eV for II, respectively.


2007 ◽  
Vol 62 (1-2) ◽  
pp. 91-100
Author(s):  
Basavalinganadoddy Thimme Gowda ◽  
Jozef Kožíšek ◽  
Ingrid Svoboda ◽  
Hartmut Fuess

The crystal structures of N-(meta-substituted phenyl)-2,2,2-trichloro-acetamides such as N- (3-methylphenyl)-2,2,2-trichloro-acetamide, 3-CH3C6H4NH-CO-CCl3 (3MPTCA); N-(3-chlorophenyl)- 2,2,2-trichloro-acetamide, 3-ClC6H4NH-CO-CCl3 (3CPTCA); N-(3,5-dimethylphenyl)- 2,2,2-trichloro-acetamide, 3,5-(CH3)2C6H3NH-CO-CCl3 (35DMPTCA) and N-(3,5-dichlorophenyl)- 2,2,2-trichloro-acetamide, 3,5-Cl2C6H3NH-CO-CCl3 (35DCPTCA) have been determined at room temperature. The crystal system, space group, formula units and lattice constants (Å ) of the new structures are: 3MPTCA: orthorhombic, Pbca, Z = 8, a = 12.3199(11), b = 8.9719(8), c = 20.2058(15); 3CPTCA: orthorhombic, Fdd2, Z =16, a=19.285(4), b=40.765(8), c=5.5920(11); 35DMPTCA: triclinic, P1̄, Z = 2, a = 8.994(4), b = 9.9890(10), c = 14.760(5), α = 79.56(2)°, β = 73.32(3)°, γ = 86.47(2)°; and 35DCPTCA: orthorhombic, Pbca, Z = 8, a = 22.485(5), b=10.738(2), c=10.028(3). The compound 35DMPTCA has two molecules in its asymmetric unit, similar to o-NO2-, m-NO2- and p-CH3-substituted phenyl-trichloro-acetamides, while 3MPTCA, 3CPTCA and 35DCPTCA have one molecule each in their asymmetric units. The analysis of data indicates that the substitution of a strong electron withdrawing group such as a nitro group into PTCA at ortho or meta positions has a significant effect on the crystal parameters.


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