Kristallstrukturen der Komplexe Von Quecksilber(Ii)Iodid und -Thiocyanat mit L,13-Bis(8-Chinolyl)-L,4,7,10,13-Pentaoxatridecan („Kryptand 5“)

2000 ◽  
Vol 55 (10) ◽  
pp. 971-974 ◽  
Author(s):  
Joachim Pickardt ◽  
Sven Wiese

AbstractReactions of 1,13-bis(8-chinolyl)-1,4,7,10,13-pentaoxatridecane (“Cryptand 5”) with HgX2 (X = I, SCN) yield crystals of [(cryptand 5)(HgI2)2] (1) and [(cryptand 5 )2{Hg(SCN)2}4] (2), resp. In both complexes two molecules of HgX2 are bound to one ligand molecule. 1 has symmetry Ci with the oxygen atom O(3 ) of the ether chain on a center of symmetry of the unit cell, each Hg atom is bound to the two I atoms, the N atom of the chinolyl residue, and one oxygen atom, O(1) and O(l)i, resp. of the ligand; neighbouring complex units are connected via iodine bridges thus forming chains. In 2 also two formula units of HgX2 are bound to one ligand molecule, but contrary to 1 the complex is not centrosymmetric. The Hg atoms of the two Hg(SCN)2 groups are co-ordinated differently: both are bound via sulphur atoms to two SCN-groups, one being a terminal SCN group, the other acting as a bridge to the Hg atom of a neighbouring complex unit. The first Hg atom is connected to a chinolyl N atom and too oxygen atoms, the second to a chinolyl N atom and three oxygen atoms. There are two independent complex units per asymmetric unit which are related by a non-crystallographic twofold axis, and which are connected via two SCN bridges. These “double molecules” are also interconnected by thiocyanate bridges, thus forming a chain structure

2006 ◽  
Vol 61 (11) ◽  
pp. 1383-1390 ◽  
Author(s):  
Irena Senkovska

Crystals of [Ca(NTC)(H2O)2]·H2O (1) (NTC = naphthalene-1,4,5,8-tetracarboxylate-1,8-monoanhydride) and [Sr2(NTC)2(H2O)8]·H2O (3) were obtained by layering an aqueous solution of sodium naphthalene-1,4,5,8-tetracarboxylate with an aqueous solution of CaCl2 or SrCl2, respectively. Crystals of [Sr(NTC)(H2O)2]·2H2O (2) and [Ba(NTC)(H2O)2] (4) were obtained by gel crystallisation. The NTC in 1 and 2 is tridentate, and in 4 pentadentate, forming bonds to the cations using the oxygen atoms of the carboxylate and one oxygen atom of anhydride groups. In 3 the cations are associated only via the oxygen atoms of carboxylate groups. 1 and 2 have layer structures, 3 has a chain structure, and 4 forms a three-dimensional coordination network. The number of O atoms around the cations is eight for 1, 2 and 4, and nine for 3.


2014 ◽  
Vol 70 (5) ◽  
pp. m170-m171
Author(s):  
Fei-Lin Yang ◽  
Dan Yang

The asymmetric unit of the title compound, {[Mn3{W(CN)8}2(C16H16N2)3(C3H7NO)3(CH3OH)3]·2H2O}n, consists of three [Mn(N,N-dimethylformamide)(methanol)(3,4,7,8-tetramethyl-1,10-phenanthroline)]2+cations, two [W(CN)8]3−anions and two water molecules. Each water molecule is disordered over three sets of sites, with a refined occupancy ratio of 0.310 (9):0.275 (9):0.415 (9) for one molecule and 0.335 (9):0.288 (9):0.377 (9) for the other molecule. The MnIIatoms exhibit a distorted octahedral geometry, while the WVatoms adopt a distorted square-antiprismatic geometry. The MnIIand WVatoms are linked alternatively through cyanide groups, forming a tetranuclear 12-atom rhombic metallacycle. Adjacent metallacycles are further connected by μ2-bridging cyanide anions, generating a 3,2-chain structure running parallel to [101]. Interchain π–π interactions are observed [centroid–centroid distances = 3.763 (3) and 3.620 (2) Å].


2001 ◽  
Vol 7 (S2) ◽  
pp. 358-359
Author(s):  
János L. Lábár ◽  
Lajos Tόth ◽  
István Dόdony ◽  
Jerzy Morgiel

Garnets were one of the first materials in which an occupation of separate lattice sites by different atomic species was determined with an ALCHEMI technique proposed by Spence and Tafto in l982. The reason of so much interest in this material was twofold, i.e. first its known high sensitivity of X-ray generation depending on orientation especially in the axial orientation and second its complicated crystal structure allowing different atomic arrangements in the unit cell depending on its chemical composition. The dodecahedral (X), octahedral (Y) and tetrahedral (Z) sites between the relatively large oxygen atoms can be filled with a variety of small cations in accordance with the formula X3Y2Z3O12. Partial substitution of one cation with another is common in this structure. The results presented in the previous literature indicated that ALCHEMI can only separate the Y-sites from the sum of the other two (X+Z), while the latter has to remain unresolved.


1974 ◽  
Vol 29 (1-2) ◽  
pp. 10-12 ◽  
Author(s):  
Horst Sabrowsky ◽  
Welf Bronger ◽  
Dieter Schmitz

The ternary oxide K2PdO2 has been prepared by a reaction between K2O and PdO. X-ray investigations suggest a chain-structure-type which corresponds to that of K2PtS2. The planar oxygen coordinations of the palladium atoms are connected laterally in one dimension. The orthorhombic unit cell (a = 8.523, b = 6.089, c = 3.119 Å) contains two formula units.


The first study of an aromatic molecule by neutron diffraction, leading to a Fourier projection of the neutron scattering density in the unit cell, gives a value of 1·08 ± 0·04 Å for the length of the C—H bonds which link hydrogen atoms to the benzene ring. The spirals of hydrogen bonds which bind together neighbouring molecules are found to consist of typical ‘long bonds’, with the proton much closer to one oxygen atom than to the other. The O—H distance is 1·02 Å, and it appears that the O, H, O atoms are not collinear.


2012 ◽  
Vol 68 (6) ◽  
pp. o1763-o1764
Author(s):  
Ya-Jie Zhang ◽  
Yan Sun ◽  
Shu-Mei Gao ◽  
Xiao-Qing Jiang ◽  
Yu-Heng Deng

The asymmetric unit in the title compound, C33H34N2O2·H2O, consists of a V-shaped molecule and a water molecule to which it is hydrogen bonded. The angle between the mean planes of the two spiro-connected indane groups is 77.06 (5)°. The two five-membered rings of the indane groups have envelope conformations with the methylene atoms adjacent to the spiro C atom forming the flaps. They have deviations from the mean plane of the other four atoms in the rings of 0.374 (4) and 0.362 (4) Å. In the crystal, molecules are linked to form inversion dimers via O—H...N hydrogen bonds involving the pyridine N atoms and the solvent water molecule. The dimers are linked into a chain along the b axis by π–π stacking interactions between a pyridine ring and its centrosymmetrically related ring in an adjacent dimer. The centroid–centroid distance between the planes is 3.7756 (17) Å, the perpendicular distance is 3.4478 (11) Å and the offset is 1.539 Å.


1967 ◽  
Vol 45 (20) ◽  
pp. 2297-2302 ◽  
Author(s):  
P. K. L. Au ◽  
C. Calvo

Cadmium pyrovanadate crystallizes in the C2/m space group with lattice parameters a = 7.088(5) Å, b = 9.091(5) Å, c = 4.963(5) Å, β = 103°21(5)′, and z = 2. This crystal is an isostructure of the mineral thortveitite and thus the anion consists of a pair of centrosymmetrically related corner-sharing VO4 tetrahedra while the cation resides within a distorted octahedron of oxygen atoms. The anion has a linear V—O—V group, but, as with the isostructural pyrophosphates, the central oxygen atom shows an anomalously high thermal activity. The V—O bond distances are 1.76 Å for the inner bond and 1.70 Å for the terminal bond. The bond angles about the anion and cation are similar to those found for the other analogues of thortveitite.


2012 ◽  
Vol 68 (8) ◽  
pp. o2427-o2428
Author(s):  
Ebtehal S. Al-Abdullah ◽  
Ali A. El-Emam ◽  
Hazem A. Ghabbour ◽  
Suchada Chantrapromma ◽  
Hoong-Kun Fun

In the asymmetric unit of the title adamantyl derivative, C20H25N3S, there are two crystallographic independent molecules with slightly different conformations. In one molecule, the whole benzyl group is disordered over two orientations with the refined site-occupancy ratio of 0.63 (2):0.37 (2). The dihedral angles between the 1,2,4-triazole and phenyl rings are 24.3 (8) (major component) and 25.8 (13)° (minor component) in the disordered molecule, whereas the corresponding angle is 51.53 (16)° in the other molecule. In the crystal, molecules are linked into a chain along theaaxis by a weak C—H...N interaction. Weak C—H...π interactions are also observed.


2014 ◽  
Vol 70 (5) ◽  
pp. m173-m173 ◽  
Author(s):  
Md. Serajul Haque Faizi ◽  
Pratik Sen

In the mononuclear title complex, [HgCl2(C16H12N2O)], synthesized from the phenolic Schiff base 4-[(quinolin-2-ylmethylidene)amino]phenol (QMAP), the coordination geometry around Hg2+is distorted tetrahedral, comprising two Cl atoms [Hg—Cl = 2.3565 (12) and 2.5219 (12) Å] and two N-atom donors from the QMAP ligand,viz.one imine and the other quinoline [Hg—N = 2.392 (2) and 2.237 (2) Å, respectively]. In the crystal, O—H...Cl hydrogen bonds generate a chain structure extending along thec-axis direction. Weak C—H...Cl and π–π stacking interactions [minimum ring centroid separation = 3.641 (3) Å] give an overall layered structure lying parallel to (001).


2012 ◽  
Vol 68 (8) ◽  
pp. o2343-o2343
Author(s):  
Xin Zhu ◽  
Qiujuan Ma

The title compound, C11H12N2O6, crystallizes with two independent molecules in the asymmetric unit, which differ slightly in conformation. The dihedral angle between the amide O=C—N plane and the attached benzene ring is 19.5 (3)° in one molecule and 23.4 (3)° in the other. In the crystal, the two independent molecules are connected alternately by N—H...O hydrogen bonds, forming a chain along theaaxis.


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