화학공학소재연구정보센터
Inorganic Chemistry, Vol.50, No.14, 6762-6766, 2011
Bixbyite-Type V2O3-A Metastable Polymorph of Vanadium Sesquioxide
A metastable polymorph of vanadium sesquioxide was prepared by the reaction of vanadium trifluoride with a water-saturated gaseous mixture of 10 vol % hydrogen in argon. The new polymorph crystallizes in the bixbyite-type structure. At temperatures around 823 K a transformation to the well-known corundum-type phase is observed. Quantum-chemical calculations show that the bixbyite-type structure is about 9 kJ/mol less stable than the known corundum-based one. This result, in combination with the absence of imaginary modes in the phonon density of states, supports the classification of the bixbyite-type phase as a metastable V2O3 polymorph. At similar to 50 K a paramagnetic to canted antiferromagnetic transition is detected.