Analysis of the structures of VO/sub 2/

Reduction of V/sub 2/O/sub 5/ by several gases and vapors produces several different vanadium oxides, one of which has the formula VO/sub 2/. This compound is not the rutile phase nor the usual monoclinic one. This new polymorph, VO/sub 2/(B), is monoclinic. The parameters are: a = 12.03 +- .10 A, b = 3.693 +- .010A, c = 6.42 +- .05 A and ..beta.. = 106.6/sup 0/ +- 1/sup 0/. The space group is C 2/M (C/sup 3//sub 2h/). X-ray powder data and the electron diffraction pattern can be interpreted on the assumption that this oxide is derived from V/sub 2/O/sub 5/ by a crystallographic shear whereby one in every two oxygen only (001) planes is eliminated and the adjacent blocks closed up by the vector 1/6 (103). This structure belongs to the same series as V/sub 6/O/sub 13/.