Ferrimagnets made by assembling high- spin organic polyradicals by mean of complexation with magnetic metal ions. Vii. One- dimensional chains made by an alternating array of mn(ll)(hfac)2 and 1,3- bis(n- oxy- tert-butylamino)benzenes

1995 ◽  
Vol 413 ◽  
Author(s):  
Katsuya Inoue ◽  
Hiizu lwamura

ABSTRACTManganese bis(hexafluoroacetylacetonate), Mn(hfac)2, reacts with a series of bisnitroxide radicals, 5- R- 1,3- bis(N- oxy- tert- butylamino)benzene 1R (R = H, Cl, and Br), to give 1:1 polymeric complexes of formula [Mn(hfac)2·1R]n. The X- ray crystal structure of the 1H complex reveals that it crystallizes in the monoclinic system, space group P21/n, with a= 9.212(3) Å, b= 16.620(3) Å, c= 20.088(2) Å, β= 98.46(1)°, V= 3042(1)Å3, and Z= 4. The manganese(II) ion and 1H molecule makes onedimensional chains by ligation of the latter serving as a bis(monodentate) ligand to the former. The crystals of the 1H complex undergo transition to a metamagnet at 5.5 K. Similar 1cl and 1Br complexes behave as ferrimagnets with transition temperatures of 5.2 and 5.0 K, respectively.

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5400
Author(s):  
Roman D. Marchenko ◽  
Taisiya S. Sukhikh ◽  
Alexey A. Ryadun ◽  
Andrei S. Potapov

Coordination polymers with a new rigid ligand 1,3-bis(1,2,4-triazol-1-yl)adamantane (L) were prepared by its reaction with cadmium(II) or silver(I) nitrates. Crystal structure of the coordination polymers was determined using single-crystal X-ray diffraction analysis. Silver formed two-dimensional coordination polymer [Ag(L)NO3]n, in which metal ions are linked by 1,3-bis(1,2,4-triazol-1-yl)adamantane ligands, coordinated by nitrogen atoms at positions 2 and 4 of 1,2,4-triazole rings. Layers of the coordination polymer consist of rare 18- and 30-membered {Ag2L2} and {Ag4L4} metallocycles. Cadmium(II) nitrate formed two kinds of one-dimensional coordination polymers depending on the metal-to-ligand ratio used in the synthesis. Coordination polymer [Cd(L)2(NO3)2]n was obtained in case of a 1:2 M:L ratio, while for M:L = 2:1 product {[Cd(L)(NO3)2(CH3OH)]·0.5CH3OH}n was isolated. All coordination polymers demonstrated ligand-centered emission near 450 nm upon excitation at 370 nm.


2021 ◽  
pp. 1-3
Author(s):  
Carina Schlesinger ◽  
Edith Alig ◽  
Martin U. Schmidt

The structure of the anticancer drug carmustine (1,3-bis(2-chloroethyl)-1-nitrosourea, C5H9Cl2N3O2) was successfully determined from laboratory X-ray powder diffraction data recorded at 278 K and at 153 K. Carmustine crystallizes in the orthorhombic space group P212121 with Z = 4. The lattice parameters are a = 19.6935(2) Å, b = 9.8338(14) Å, c = 4.63542(6) Å, V = 897.71(2) ų at 153 K, and a = 19.8522(2) Å, b = 9.8843(15) Å, c = 4.69793(6) Å, V = 921.85(2) ų at 278 K. The Rietveld fits are very good, with low R-values and smooth difference curves of calculated and experimental powder data. The molecules form a one-dimensional hydrogen bond pattern. At room temperature, the investigated commercial sample of carmustine was amorphous.


Author(s):  
Ahmet Karadag ◽  
Hümeyra Pasaoglu ◽  
Gökhan Kastas ◽  
Orhan Büyükgüngör

AbstractThe cyano-bridged heteronuclear coordination polymer of zinc(II)/nickel(II) has been prepared by N-(2-hydroxyethyl)-ethylendiamine (hydet-en), alternatively named 2-(2-aminoethylamino)-ethanol and characterised by IR and thermal analysis. In the bimetallic complex, the decomposition of hydet-en ligands is seen to be endothermic whereas that of the cyano ligands is found to be exothermic. The crystal structure of the complex has been determined by single-crystal X-ray diffraction. The crystal structure of the zinc(II)-nickel(II) complex consists of a one-dimensional polymeric chain –Zn(hydet-en)


1995 ◽  
Vol 73 (1) ◽  
pp. 95-99 ◽  
Author(s):  
Frank E. Smith ◽  
Rosemary C. Hynes ◽  
John Tierney ◽  
Ying Z. Zhang ◽  
George Eng

The title compound was synthesized as part of an effort to produce a more effective fungicide to combat Dutch Elm Disease (DED), which is caused by the fungus Ceratocystisulmi. A full X-ray structural analysis of the 1:1 adduct has been carried out and the results are reported along with the Mössbauer data for the compound. The crystals are monoclinic, space group P21/a with a = 19.240(3) Å, b = 9.1463(24) Å, c = 19.3512(24) Å, β = 118.874(8)°, V = 2982.0(10) Å3, z = 4, and Dcalc = 1.427 Mg m−3. The final discrepancy factors are RF = 0.056 and Rw = 0.058 for 1915 significant reflections. The QS and IS values in the Mössbauer spectrum of the complex are 3.08 mm s−1 and 1.28 mm s−1, respectively. The 2,3-diphenylthiazolidin-4-one behaves as a monodentate ligand and coordinates to the tin through the oxygen atom. The complex exhibits a trigonal bipyramidal configuration with the three phenyl groups in equatorial positions and the chloride and ligand oxygen occupying the apical sites. Keywords: triorganotin, fungicide, Dutch Elm Disease, thiazolidin-4-one.


1990 ◽  
Vol 68 (12) ◽  
pp. 2183-2189 ◽  
Author(s):  
Pierre Audet ◽  
Rodrigue Savoie ◽  
Michel Simard

A stoichiometric complex of formula maleic acid•2H2O•18-crown-6 has been obtained from maleic acid and the macrocyclic polyether 18-crown-6. Crystals of this complex have been shown by X-ray diffraction crystallography to belong to the Cc space group of the monoclinic system. The acid molecules in the adduct are linked to each other through a water molecule, giving infinite [-acid-H2O-]n chains. They are also linked to the crown ether via water molecules. The infrared and Raman spectra of the complex are presented and compared to those of crystalline maleic acid. Keywords: maleic acid/18-crown-6, structure, X-ray, spectra.


2009 ◽  
Vol 74 (7) ◽  
pp. 755-764 ◽  
Author(s):  
Wen-Tong Chen ◽  
Xiao-Niu Fang ◽  
Qiu-Yan Luo ◽  
Ya-Ping Xu

A novel bimetallic 4f-3d metal-isonicotinic acid inorganic-organic hybrid complex [{Eu(NC5H4COOH)3(H2O)2}(1.5ZnCl4)?(2H2O)]n (1) was synthesized via a hydrothermal reaction and structurally characterized by single- crystal X-ray diffraction. Complex 1 crystallizes in the space group C2/c of the monoclinic system with eight formula units in a cell: a = 23.878(8) ?, b = 20.573(6) ?, c = 15.358(5) ?, ? = 127.276(5)?, V = 6003(3) ?3, C18H23Cl6EuN3O10Zn1.5, Mr = 904.11 g/mol, ? = 2.001 g/cm3, S = 1.077, ?(MoK?) = 3.846 mm-1, F(000) = 3536, R = 0.0270 and wR = 0.0672. Complex 1 has a characteristic, one-dimensional polycationic chain-like structure. A photoluminescent investigation revealed that the title complex displays intense emissions in the orange and red regions. The luminescence spectra show that the red emission is stronger than the orange emission. Optical absorption spectra of 1 revealed the presence of an optical gap of 3.56 eV.


2011 ◽  
Vol 6 (11) ◽  
pp. 1934578X1100601
Author(s):  
Yang Li ◽  
Jun-Hui Zhou ◽  
Gui-Jun Han ◽  
Min-Juan Wang ◽  
Wen-Ji Sun ◽  
...  

The crystal structure of natural diterpenoid alkaloid ranaconitine isolated from Aconitum sinomontanum Nakai has been determined by single crystal X-ray diffraction analysis. The crystal presents a monoclinic system, space group C2 with Z = 4, unit cell dimensions a = 30.972(19) Å, b = 7.688(5) Å, and c = 19.632(12) Å. Moreover, the intermolecular O–H···O hydrogen bonds and weak π-π interactions play a critical role in expanding the dimensionality.


1990 ◽  
Vol 45 (10) ◽  
pp. 1416-1424 ◽  
Author(s):  
W. Preetz ◽  
P. Hollmann ◽  
G. Thiele ◽  
H. Hillebrecht

The triply bonded octahalogenodiosmate(III) anions [Os2X8]2-, previously known with X = Cl, Br, have now been extended to include the iodide with two staggered OsI4 units. This compound was prepared by treating [Os2Cl8]2- with Nal at room temperature in acetone solution. The structure determination by X-ray diffractometry on single crystals of (PPN)2[Os2I8] · 2 CH2Cl2, reveals crystallization in the monoclinic system, space group P21/c with Z = 4. The Os-Os triple bond is with 2.212(1) Å the longest within the three octahalogenodiosmates(III). The Raman spectra show ν(OsOs) at 285, [Os2Cl8]2-; at 287, [Os2Br8]2- and for the iodo compound at 270.1 cm-1 with up to three overtones. The spectroscopic constants are calculated to be ω1 = 270.9 cm-1; X11 = -0.50 cm-1. The 10 Κ UV-VIS spectra of solid [(n-C4H9)4N]2[Os2X8] exhibit δ-π* transitions with maxima at 723, 690 and 643 nm, superimposed by vibrational fine structures with long progressions of 195, 211 and 183 cm-1 for X = Cl, Br, I, respectively. Oxidation of [Os2X8]2-, X = Cl, Br with the corresponding halogen leads to the cleavage of the Os-Os bond, and the dekahalogenodiosmates(IV), [Os2X10]2-, are formed


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