ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Synthesis, crystal structure and thermal dehydration of CsMnF4 · 2H2OThe preparation of a new fluoromanganate (III)-complex CsMnF4 · 2H2O is reported. It crystallizes in the monoclinic space group C2 with a = 11.891(2) Å, b = 6.589(1) Å, c = 10.558(1) Å, β = 131.46(1)° and Z = 4. The crystal structure has been solved from diffractometer data by heavy-atom methods and refined to a conventional R-value of 1.8% (including the contributions of three hydrogen atoms in measured and one in calculated positions). The structure is characterized by isolated, tetragonally distorted [MnF4(OH2)2]-octahedra with Mn-F-distances from 1.801(8) Å to 1.870(7) Å and Mn-O-distances of 2.146(6) Å and 2.268(6) Å. Cesium exhibits an irregular 10-coordination by 8 F-atoms and 2 O-atoms (mean values for the two independent cesium ions: Cs-F = 3.17 Å and 3.21 Å, Cs-O = 3.32 Å and 3.29 Å). The [MnF4(OH2)2]-octahedra are connected to six neighbouring octahedra by hydrogen bonding.The dehydration of the complex has been studied by thermoanalytical methods and power x-ray-diffractometry. The unit cell of the dehydrated compound, CsMnF4, is tetragonal with a = 7.936(1) Å and c = 6.341(1) Å. A close relationship to the structure of CsFeF4, which is a superstructure variant of the T1A1F4-type[6], is indicated by the similarity of the corresponding unit cells and preliminary structure factor calculations. A proposition for the crystal structure of CsMnF4 is developed on the basis of (2 + 2 + 2)-orthorhombic distorted MnF6-octahedra.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19770600515
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