On the local motions in ferroelectric NaNO2 from 23Na NMR data

نویسندگان

  • Mrignayani Kotecha
  • Lakshman Pandey
  • MRIGNAYANI KOTECHA
چکیده

This article maybe used for research, teaching and private study purposes. Any substantial or systematic reproduction, redistribution , reselling , loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. Electric field gradients (efg) at the sites of sodium in the ferroelectric NaNO2 are calculated for various local motions. It is found that the values of efg obtained from 23Na NMR data are best represented when the NO2 groups are considered to be executing flipping motion by 170" about an axis whose direction cosines are 0.99,0.11,0.06 with respect to the crystal axes (c, a, b). Such a motion is in conformation with the not-so-widely known fact that the electric polarization in ferroelectric NaN02 has a spiraling orientation as one moves from one domain to the other.

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تاریخ انتشار 2007