D. Hagrman, J. Zubieta, Christopher J. Warren
Jun 1, 1998
Citations
0
Influential Citations
79
Citations
Quality indicators
Journal
IEEE Journal of Solid-state Circuits
Abstract
Abstract A novel polymorph of VO 2 , designated VO 2 (C), has been prepared by dehydration of the new layered vanadium oxide hydrate, VO 2 ·1/2 H 2 O. The hydrate is prepared in high yield as a single phase from the hydrothermal reaction of the hydrolyzate of VCl 4 and NaOH in a molar ratio of 1:4.5 for 96 hours at 200°C. The hydrate crystallizes in the tetragonal space group I 4/ mmm , with a =3.7211(6) A, c =15.421(1) A, Z =4, and R =0.045 as determined by X-ray single crystal diffraction. The structure consists of layers of VO 5 square pyramids, each of which shares its four basal edges with four neighboring VO 5 square pyramids. Water molecules that reside between the layers can be removed reversibly to give the new layered oxide VO 2 (C).