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A new zinc germanate incorporating a tetradentate amine ligand has been synthesized by the solvothermal method and structurally characterized by single-crystal X-ray diffraction, solid-state (19)F NMR spectroscopy, thermal analysis, and IR spectroscopy. Its structure contains close-packed hollow columns with an 18-membered window, each of which contains six one-dimensional chains formed of Ge(7)X(19) (X = O, OH, F) clusters connected to zinc complexes.

Durch chemische Transportreaktionen mit HCl oder Cl2 als Tranportmittel (1050 900 °C bzw. 850 750 °C) konnten die festen Losungen (ZnxCo1—x)2GeO4, and (MnxZn1—x)2GeO4 prapariert werden. ZnGeO3, das in reiner Form unbekannt ist, kann in Form von Mischkristallen (MnxZn1—x)GeO3 (x > 0, 5) stabilisiert werden. Chemical Vapor Transport of Solid Solutions 10 [1] The Chemical Vapor Transport of quarternary Cobalt(II)-Zinc and Manganese(II)-Zinc Germanates By means of chemical vapor transport methods using HCl or Cl2 as transport agent the crystalline solid solutions (ZnxCo1—x)2GeO4 and (MnxZn1—x)2GeO4 have been prepared (1050 900 °C, 850 700 °C, respectively). ZnGeO3 — although unknown as a pure solid — can be stabilized as a mixed crystal (MnxZn1—x)GeO3 (x > 0, 5).

Title compound (III) is characterized by single crystal XRD, solid state 19F NMR, and IR spectroscopy.

Despite the recent progress in the synthesis of new germanates, no zinc germanate has been synthesized by using a molecular templating route. A unique type of zincogermanate framework has now been prepared by using ethylenediamine as the structure-directing agent. The three-dimensional framework can be simply described as the face-centered packing of an elongated neutral cluster unit, Ge9O18.

Cobalt-doped dicalcium zinc germanate, synthesized by slow cooling from the melt, is monoclinic and has a layered structure, which is different from the modulated melilite-type structure of Ca2ZnGe2O7. The monoclinic form has two different Ca, one Zn and two Ge sites, and seven independent O-atom positions; all are in general position 4e of the space group P21/n. The topology of the structure is described and compared with that of Ca2ZnGe1.25Si0.75O7.

Despite the recent progress in the synthesis of new germanates, no zinc germanate has been synthesized by using a molecular templating route. A unique type of zincogermanate framework has now been prepared by using ethylenediamine as the structure-directing agent. The three-dimensional framework can be simply described as the face-centered packing of an elongated neutral cluster unit, Ge9O18.

A single-crystal diffraction study has been carried out at 145 K, 195 K and 300 K to investigate the phase relations of BaZnGeO4. The space group of phase VI has been found to be P6122 or P6522 with the lattice parameters aVI=5.32 Å and c_VI=26.1 Å a t 145 K. T h e s y m m e t r y i s h i g h e r t h a n t h a t o f t h e r o o m-t e m p e r a t u r e p h a s e I I I. A n e w p h a s e, V I I, h a s b e e n f o u n d i n t h e s a m p l e l a r g e r t h a n 0.2 m m a n n e a l e d i n t h e t e m p e r a t u r e r a n g e o f 100-160 K f o r a b o u t 1 m o n t h. T h i s p h a s e i s t h o u g h t t o h a v e a h e x a g o n a l s y m m e t r y (P6_3 o r P6_3/m) w i t h t h e l a t t i c e p a r a m e t e r sa_VII=10.68 Å a n dc_VII=8.69 Å. S i n c e p h a s e V I d i d n o t a p p e a r i n t h e c a s e o f c r y s t a l s s m a l l e r t h a n 0.2 m m, t h e p a r t i c l e s i z e e f f e c t o n t h e V-V I p h a s e c h a n g e h a s b e e n c o n f i r m e d. T h e r e l a t i o n s h i p s a m o n g p h a s e s I, I I, I I I, I I I', I V, V, V I a n d V I I o f B a Z n G e O_4 a r e d i s c u s s e d.

We have observed the EPR spectra of divalent manganese in zinc germanate single crystals and solid state reacted powders. Two distinct spectra are seen which are interpreted in terms of Mn2+ substituting for Zn2+ in its two inequivalent sites. For one of the sites D=742×10−4cm−1 and E=192×10−4cm−1, and for the other site D=481×10−4cm−1 and E=156×10−4cm−1.