1 research outputs found
Trigonal-Bipyramidal Coordination in First Ammoniates of ZnF<sub>2</sub>: ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>3</sub> and ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>2</sub>
No full textSingle crystals of
ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>3</sub> and ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>2</sub> were obtained under ammonothermal conditions
(250 °C, 196 MPa and 500 °C, 136 MPa). Upon thermal decomposition
of both ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>3</sub> and ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>2</sub>, a microcrystalline powder of ZnF<sub>2</sub>(NH<sub>3</sub>) was obtained. ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>3</sub> and ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>2</sub> represent
probable intermediates in a conceivable ammonothermal synthesis of
the semiconductor Zn<sub>3</sub>N<sub>2</sub> and manifest a rare
trigonal-bipyramidal coordination of F<sup>–</sup> and NH<sub>3</sub> ligands around Zn<sup>2+</sup> according to single-crystal
X-ray diffraction. Thermal analysis of all three compounds showed
not only ZnF<sub>2</sub>(NH<sub>3</sub>) but also ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>2</sub> to be decomposition intermediates of ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>3</sub> prior to the formation of ZnF<sub>2</sub>. All three compounds demonstrate hydrogen bonds, as indicated
by the intensities and half-widths of the bands in the vibrational
spectra and by short N–H···F distances in the
crystal structures of ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>3</sub> and
ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>2</sub>. With ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>3</sub>, ZnF<sub>2</sub>(NH<sub>3</sub>)<sub>2</sub>, and ZnF<sub>2</sub>(NH<sub>3</sub>), we present the first ammoniates
of ZnF<sub>2</sub>
