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Journal of Materials Science

, Volume 7, Issue 3, pp 298–302 | Cite as

High-pressure phase research on Nb2O5

  • S. Tamura
Papers

Abstract

Experimental results indicate that the direct transitions from the H form to the T form and from the H form to the B form of Nb2O5 are possible under high pressures. Both highly pure and less pure reagents were used. The distinct TT form was obtained only when less pure reagents were used so that the TT form seems to be stabilised by means of trace impurities. Previously the TT form was indexed as having a pseudohexagonal unit cell. However, the present distinct TT form has a monoclinic unit cell,a=7.238Å,b=15.79Å,c=7.188Å,β=119°59′,V=711.7(Å)3. Eight molecules are contained per cell. Probably only B, T and H have stable regions; the other polymorphs of Nb2O5 may be metastable forms or forms stabilised by impurities.

Keywords

Polymer High Pressure Stable Region Nb2O5 Direct Transition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Chapman and Hall Ltd 1972

Authors and Affiliations

  • S. Tamura
    • 1
  1. 1.National Institute for Researches in Inorganic MaterialsTokyoJapan

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