Kruthika G, Karthikeyan J, Murugan P
Functional Materials Division, CSIR Central Electrochemical Research Institute (CECRI), Karaikudi-630 003, Tamil Nadu, India and Academy of Scientific & Innovative Research, CECRI, India.
Phys Chem Chem Phys. 2017 Feb 1;19(5):3770-3776. doi: 10.1039/c6cp07259c.
By employing first principles density functional calculations, we investigated an α-MnO compound with a tunnel framework, which provides an eminent platform to alter the intrinsic antiferromagnetic (AFM) to ferromagnetic (FM) ordering, through the introduction of chemical or mechanical tensile strain. Our calculations further showed that the strength of FM ordering increases until 10% triaxial tensile strain. Since long range FM ordering is induced, it is realized to be superior as compared to the experimentally observed short-range FM ordering in oxygen-deficient compound. The driving force behind this superior effect is understood from the unusual electron occupancy in Mn atoms as a result of tetrahedral distortion in the MnO octahedra and an increase in the sp character of the oxygen atoms. Thus, the α-MnO compound belongs to a class of materials that exhibit good potential for piezomagnetic applications.
通过采用第一性原理密度泛函计算，我们研究了一种具有隧道结构的α-MnO化合物，该结构通过引入化学或机械拉伸应变，为将本征反铁磁（AFM）转变为铁磁（FM）有序排列提供了一个卓越的平台。我们的计算进一步表明，直到10%的三轴拉伸应变，FM有序排列的强度都会增加。由于诱导出了长程FM有序排列，与在缺氧化合物中实验观察到的短程FM有序排列相比，它被认为更具优势。这种优越效应背后的驱动力可以从MnO八面体中的四面体畸变导致的Mn原子中异常的电子占据以及氧原子的sp特征增加来理解。因此，α-MnO化合物属于一类在压磁应用中具有良好潜力的材料。
