Synthese, Kristallstruktur und thermische Entwässerung von CsMnF 4 · 2H 2 O
1977; Wiley; Volume: 60; Issue: 5 Linguagem: Inglês
10.1002/hlca.19770600515
ISSN1522-2675
AutoresE. Dubler, Lothar Linowsky, Jean‐Pierre Matthieu, Hans‐Rudolf Oswald,
Tópico(s)Inorganic Chemistry and Materials
ResumoSynthesis, crystal structure and thermal dehydration of CsMnF 4 · 2H 2 O The preparation of a new fluoromanganate (III)‐complex CsMnF 4 · 2H 2 O is reported. It crystallizes in the monoclinic space group C 2 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 [MnF 4 (OH 2 ) 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 [MnF 4 (OH 2 ) 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, CsMnF 4 , is tetragonal with a = 7.936(1) Å and c = 6.341(1) Å. A close relationship to the structure of CsFeF 4 , which is a superstructure variant of the T1A1F 4 ‐type[6], is indicated by the similarity of the corresponding unit cells and preliminary structure factor calculations. A proposition for the crystal structure of CsMnF 4 is developed on the basis of (2 + 2 + 2)‐orthorhombic distorted MnF 6 ‐octahedra.
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