ISSN:
1434-4475
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
Notizen:
Abstract Manganese(II) phosphites MnHPO3·3.6 H2O, Mn3H6P4O12·1.5 H2O, MnH4P2O6·H2O, Mn2H11P5O15·4 H2O, Mn2H17P7O21· 4 H2O and MnH10P4O12·H2O have been studied by IR spectroscopy, thermography and magnetic measurements. Based on the results obtained, the following structural model is proposed: in the compounds studied, each Mn(II) ion is surrounded octahedrally by the oxygen atoms of water molecules and phosphite or polyorthophosphite anions. In the phosphite MnHPO3·3.6H2O the C3v symmetry of the anion decreases to Cs. The anion is characterized by the bond lengthsr PO=1.49 Å and $$r_{PO_2 }$$ =1.52 Å, force constantsK PO=7.8 mdyn/Å and $$K_{PO_2 }$$ =6.4 mdyn/Å and bond ordersN PO=1.68 and $$N_{PO_2 }$$ =2.03. Apart from the interaction between this deformed anion and the Mn(II) cation, hydrogen bonds of approximate length 2.84 Å and energy 5.0 kcal/mole are formed in the phosphite mentioned, linking the water molecules in the coordination sphere. In the other phosphites studied, the following types of hydrogen bond are found: hydrogen bonds linking hydrate water molecules, those between water molecules and the anion, and another systems of hydrogen bonds in the polyorthosphite anions.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00910270
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