ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The crystal and molecular structure of [La(NO3)3]4(C12H26O5)3 has been determined from low-temperature single-crystal X-ray diffraction data. The complex crystallizes in the monoclinic space group I2 with Z = 2. Lattice parameters at 150 K are a = 12.234 (6) Å, b = 11.105 (5), c = 26.613 (9), β = 90.65 (4)°. The structure was solved by Patterson and Fourier techniques and refined to a conventional RF-value of 0.068. The compound contains three dinitrato complex cations [La(NO3)2C12H26O6]+ with 10-coordinate lanthanum ions and one hexanitrato anion, [La(NO3)6]3-, with a 12-coordinate La(III)-ion. One complex cation has a C2-symmetry while the two others, which are crystallographically equivalent, have no symmetry and contain a disordered ligand molecule. The polyther adopts a ring-like conformation in all the complex moietis. The La—O(nitrate) distances lie in the ranges 2.52-2.53 and 2.49-2.62 Å, with average values of 2.53 (7) and 2.56 (6) Å, respectively, fo the species with C2- and C1-symmetry; the La—O(ether) bond lengths lie int he range 2.54-2.79 Å (average: 2.6 (1)) for the C2-moiety and their mean value amounts to 2.6 (2) for the disordered species. The hexanitrate has a C2-symmetry and the La—O distances range between 2.56 and 2.67 Å with an average value fo 2.64 (4) Å. The effective ionic radii of the 10- and 12-coordinate La(III) ions are estimated as 1.28 and 1.33 Å, respectively.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19840670426
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