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Dear all,<BR>
i am trying to calculate polarization in ferroelectric materials with Aurivillius structure (tetragonal and orthorombic), but i often get two anomalies: negative polarization and polarization close to the "quantum" polarization. as an example: P= -0.23 (mod 0.248) C/m2.<BR>
could someone explain me that? i'll be grateful.<BR>
<BR>
Hania Djani<BR>
Phd student<BR>
centre for development of advanced technologies<BR>
Algiers, Algeria<RTE_TEXT></RTE_TEXT><BR><br /><hr />Appelez vos amis de PC à PC -- C'EST GRATUIT <a href='http://get.live.com/messenger/overview' target='_new'>Téléchargez Messenger, c'est gratuit !</a></body>
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