摘要
基于Kikuchi自洽迭代方法,利用有序-无序相变理论,并取最近邻相互作用近似,研究了Pb(Mg_((1+x)/2)Nb_((2-x)/2)O_3晶粒中在x=0.5时有序区形成的原因,提出Mg^(2+)∶Nb^(5+)=1∶1(离子数比)时,形成B位有序排列最为有利,并且弱的空间电荷场不影响这种有序排列的形成,同时给出了温度-组份的有序-无序相图。
Based on Kikuchi's natural iteration method, the reason of the formation of ordered srate with Mg_2^(2+)Nb^(5+)=1:1 in the grain of Pb(Mg_((1+x)/3)Nb_((2-x)/3)O_3 was studied by means of order-disorder transition model, taken the nearest neighbour interaction as an approximation. The theoretical results show that the atoms on B-site are most favorable for ordered arrangement in some areas when Mg_2^(2+)Nb^(5+)=1:1, and the ordered state can not be influenced by the weak space charge field resulted from ordered arrangement. Besides, the order-disorder transition diagram is also presented.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
1989年第5期412-416,共5页
Journal of The Chinese Ceramic Society
关键词
铁电材料
有序无序相变
自洽迭代法
order-disorder transition
self-consistent iteration method
sublattice
space charge field
