Crystal and molecular structure of CuCo(fsa)2en.6H2O(H4(fsa)2en = N,N'-bis(2-hydroxy-3-carboxybenzylidene)-1,2-diaminoethane): an example of close-packed association of two heterobinuclear units through the formation of a water molecule network

1980 ◽  
Vol 19 (10) ◽  
pp. 2945-2948 ◽  
Author(s):  
Jean Galy ◽  
Joel Jaud ◽  
Olivier Kahn ◽  
Pierre Tola
1983 ◽  
Vol 61 (7) ◽  
pp. 1651-1658 ◽  
Author(s):  
Raymond M. Morrison ◽  
Robert C. Thompson ◽  
James Trotter

Reaction of aqueous solutions containing CO2+ or Ni2+ and PF6−, or AsF6− with excess 3-methylpyridine yields crystals of compounds of composition M(H2O)2(3mpy)6(EF6)2. Blue crystals of diaquohexakis(3-methylpyridine)nickel(II) hexafluorophosphate, C36H46F12NiN6O2P2, are monoclinic, a = 10.497(1), b = 20.074(3), c = 21.836(5) Å, β = 103.93(2)°, Z = 4, space group Cc. The structure was determined with MoKα CAD4 diffractometer data by direct methods, and refined by full-matrix least-squares procedures to R = 0.048 for 2723 reflections with I ≥ 3σ(I). The structure consists of {Ni(3mpy)4[(OH2)(3mpy)]2}2+ cations and PF6− anions. The cation contains a NiN4O2 chromophore with water molecules occupying trans positions of a distorted octahedron about nickel. One additional 3-methylpyridine molecule is H-bonded to each of the water molecules with [Formula: see text] distances of 2.717(11) and 2.719(11) Å. Weak interaction of each water molecule via its second hydrogen atom with a PF6− ion is indicated by the positioning of the anions. The [Formula: see text] distances are 2.958(11) and 2.959(11) Å. Two other complexes of this type, where M is Ni and E is As and where M is Co and E is P, are reported here and on the basis of spectroscopic and magnetic studies are assigned structures similar to the Ni/P complex.Decomposition of the aquo complexes under mild conditions yields compounds of composition M(3mpy)4(EF6)2. Ni(3mpy)4(PF6)2 is assigned a square planar structure with weakly interacting PF6−, anions in axial positions. Both Co(3mpy)4(EF6)2 complexes, where E is P or As, have tetrahedral [Co(3mpy)4]2+ cations and non-coordinated anions.


1987 ◽  
Vol 52 (8) ◽  
pp. 1915-1921 ◽  
Author(s):  
Charles Kappenstein ◽  
Juraj Černák

Cd(NH3)2Ni(CN)4.0·5 H2O is orthorhombic, Imma, with parameters a = 0·7622(4), b = 1·4992(13), c = 0·8961(6) nm, Z = 4, d(exp) = 2·07(4), d(calc.) = 2·066 Mg m-3. The structure, which was refined by the least squares method to R = 0·038 for 1 508 independent reflections, is isostructural with Ni(NH3)2Ni(CN)4.0·5 H2O and consists of infinite layers of the [Cd(NC)4Ni] type. Two water molecules in the unit cell occupy 4 equivalent positions between the layers. The shortest intermolecular distances 0·3023(2) (H2O···Ni) and 0·3371(1) nm (H2O···NH3) indicate zeolitic character of the water molecule.


2018 ◽  
Vol 59 (1) ◽  
pp. 191-195
Author(s):  
A. N. Azizova ◽  
◽  
D. B. Tagiev ◽  
S. N. Osmanova ◽  
Sh. G. Kasumov ◽  
...  

1981 ◽  
Vol 46 (1) ◽  
pp. 6-19 ◽  
Author(s):  
Viktor Kettman ◽  
Ján Garaj ◽  
Jaroslav Majer

The crystal and molecular structure of [Cr(S2CN(CH2)5)3].2 CHCl3 was found by the X-ray structural analysis method. The value R 0.090 was found for 1 131 observed independent reflections. The substance crystallizes in a space group of symmetry P212121 with the following unit cell dimensions: a = 0.8675 (6), b = 1.815(2), c = 2.155(3) nm. The experimentally observed crustal density was 1.48 Mgm-3 and the value calculated for Z = 4 was 1.51 Mgm-3. The CrS6 coordination polyhedron has the shape of a trigonally distorted octahedron, where the D3 symmetry is a approximately retained. The degree of trigonal distortion expressed as the projection of the chelate S-Cr-S angle onto the plane perpendicular to the C3 pseudo axis is Φ = 41.7° (Φ = 60° for an octahedron). The skeleton of the structure formed by the complex molecules contains channels filled with chloroform molecules. The specific type of complex-chloroform interaction consists of the formation of hydrogen bonds of the chloroform protons with the fully occupied pπ-orbitals of the sulphur atoms in the coordination polyhedra. The low stability and crystal decomposition can be explained by loss of chloroform from the channels.


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