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1	Author		Requires cookie*
	Title	Über Isopolymolybdatfeststoffe und deren Beziehung zu Isopolymolybdationen in wäßriger Lösung* Concerning Solid Isopolym olybdates an d th e ir R elation to Isopolym olybdate Ions in Aqueous Solution
	Abstract	After a brief discussion on the output capacity of the methods used for the study of the isopolymetalates, a classification and characterization of the solid isopolymolybdates obtainable from aqueous solution is given, and the relation of the solid isopolymolybdates to the isopolymolybdate ions in solution is studied. A correlation between the occurrence or non-occurrence of a species in a solid and in its solution detectable by Raman spectro scopy, the solubility of the solid, and the time necessary for the formation of the solid was found. This gives important informations on the mechanisms of formation of the iso-polym etalate ions. The m ost remarkable result of this investigation is that contrary to the view of the majority of the papers on this subject the octamolybdate ion Mo80 264_ having the structure found by L i n d q v i s t does not occur in important quantities in solution at room temperature. For setting up a reaction scheme on the isopolymolybdates only very few of the confusing multiplicity of the papers give evidentiary informations. Most of the papers are overinterpreted.
	Reference	(Z. Naturforsch. 30b, 471—484 [1975]; eingegangen am 21. Februar 1975)
	Published	1975
	Keywords	Isopolyanions, Isopolymolybdates, Fingerprint Raman Spectroscopy, Reaction Mechanisms
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	TEI-XML for	default:Reihe_B/30/ZNB-1975-30b-0471.pdf
	Identifier	ZNB-1975-30b-0471
	Volume	30

2	Author	Karl-Heinz Tytko	Requires cookie*
	Title	Über den Mechanismus der Bildung von Polyanionen in wäßriger Lösung. Zum Bildungsmechanismus eines Polytetramolybdations [Mo4014 4-]» On the Mechanism of Formation of Polyanions in Aqueous Solution. Concerning the Mechanism of Formation of a Polytetramolybdate Ion [Mo4014 4 ~]«
	Abstract	Possible structures and the pertinent reaction pathways for the polymetalate ion present in a slightly soluble polymetalate having the analytical formula A20 • 2 MO3 have been derived on the basis of theoretical considerations. Structure and kind of combination of the tetrameric units of one of the possibilities are in agreement with the results of X-ray structure analyses. First the previously proposed planar tetrametalate ion [M40i2(0H)4] 4_ is formed by stepwise aggregation according to an addition mechanism. This species undergoes a rearrangement of the coordination sphere of two of the M atoms and is then subject to a poly condensation resulting in a polytetrametalate chain, [M40i4 4_ ]n.
	Reference	(Z. Naturforsch. 31b, 737—748 [1976]; eingegangen am 2. Januar/16. Dezember 1975)
	Published	1976
	Keywords	Isopolyanions, Isopolymolybdates, Reaction Mechanisms, Polymetalate Structures
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	TEI-XML for	default:Reihe_B/31/ZNB-1976-31b-0737.pdf
	Identifier	ZNB-1976-31b-0737
	Volume	31

3	Author	Tetraphenylphosphonium-Isopolymolybdates, Roger Grase, Joachim Fuchs	Requires cookie*
	Title	Über Tetraphenylphosphonium-Isopolymolybdate
	Abstract	From acidified sodium molybdate solutions mixtures of two polymolybdates are precipitated by addition of tetraphenylphosphonium ions. The pure compounds obtainable by separation with selective organic solvents were identified analytically and by their vibrational spectra as octamolybdate, [P(C6Hs)4]4Mo8026, with "Lindqvist structure" and as hexamolybdate, [P(C6Hs)4Mo60i9. They are characterized by their UV-VIS spectra and X-ray powder patterns. The precipitation of the hexamolybdate from strong acidic solution can be used analytically for the determination of molybdenum.
	Reference	Z. Naturforsch. 33b, 533—536 (1978); eingegangen am 20. Januar 1978
	Published	1978
	Keywords	Isopolymolybdates, Preparation, Vibrational Spectra, X-ray, UV
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	TEI-XML for	default:Reihe_B/33/ZNB-1978-33b-0533.pdf
	Identifier	ZNB-1978-33b-0533
	Volume	33