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Inorganic Materials

, Volume 36, Issue 6, pp 625–628 | Cite as

High-pressure polymorph of LaNbO4

  • Yu. A. Titov
  • A. M. Sych
  • A. N. Sokolov
  • A. A. Kapshuk
  • V. P. Yashchuk
Article

Abstract

A new polymorph of LaNbO4 with a BaMnF4-type structure(a = 0.3938(2) nm,b = 1.442(1) nm,c = 0.5682(3) nm,Z = 4) and octahedral oxygen coordination of Nb was prepared at high pressures and temperatures (8 GPa, 1570 K). At normal pressure, the reverse transformation, from high-pressure LaNbO4 to theM-fergusonite form, occurs at temperatures above 870 K and is close to a second-order phase transition. The spontaneous polarization in high-pressure LaNbO4, evaluated from the second-order nonlinear optical response, is about 2 ώC/cm2.

Keywords

Second Harmonic Generation Scheelite Spontaneous Polarization Layered Perovskite LaNbO4 
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

© MAIK “Nauka/Interperiodica” 2000

Authors and Affiliations

  • Yu. A. Titov
    • 1
  • A. M. Sych
    • 1
  • A. N. Sokolov
    • 2
  • A. A. Kapshuk
    • 1
    • 2
  • V. P. Yashchuk
    • 1
  1. 1.Shevchenko National UniversityKievUkraine
  2. 2.Bakul’ Institute of Superhard MaterialsNational Academy of Sciences of UkraineKievUkraine

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