CAJ | 학술논문

利用第一性原理系统地研究了RbH_2PO_4晶格优化结构、总的和分的态密度、电荷密度分布.我们发现氧原子和Rb,H原子的杂化形成了两种离子群,在铁电相离子键和PO_4四面体的耦合强度比顺电相更强.结果,通过P-O 和 H-O的距离改变电荷密度的再分布和PO_4四面体的顺序旋转导致了铁电性的产生.两种类型粒子群的运动和自动成型畴壁导致了可以观测的焦热电流.
이용제일성원리계통지연구료RbH_2PO_4정격우화결구、총적화분적태밀도、전하밀도분포.아문발현양원자화Rb,H원자적잡화형성료량충리자군,재철전상리자건화PO_4사면체적우합강도비순전상경강.결과,통과P-O 화 H-O적거리개변전하밀도적재분포화PO_4사면체적순서선전도치료철전성적산생.량충류형입자군적운동화자동성형주벽도치료가이관측적초열전류.
First-principles calculations are performed for the study of RbH_2PO_4 with the lattice optimized structure,Electronic bands,total and partial densities of states as well as charge density distribution are analyzed systematically.It is noted that oxygen atomic hybridize with Rb,and H,there exist two-type ionic groups.The couple strength between the cation bonds and the PO_4 tetrahedra in the ferroelectric phase is stronger than that in the paraelectric phase.As a result,the redistribution of charge density by change of P-O and H-O distance and the subsequent rotations of the PO_4 tetrahedra can lead to the driving force of the ferroelectric behaviors.The motion of two-type ionic groups,relating to atomically shape domain walls,can lead to the measurable pyroelectric current.