Orio M, Bindra J K, van Tol J, Giorgi M, Dalal N S, Bertaina S
CNRS, Aix-Marseille Université, Centrale Marseille, iSm2, Institut des Sciences Moléculaires de Marseille, Marseille, France.
Department of Chemistry, Florida State University, Tallahassee, Florida 32310, USA.
J Chem Phys. 2021 Apr 21;154(15):154201. doi: 10.1063/5.0046984.
Dimethylammonium magnesium formate, [(CH)NH][Mg(HCOO)] or DMAMgF, is a model used to study high temperature hybrid perovskite-like dielectrics. This compound displays an order-disorder phase transition at about 260 K. Using multifrequency electron spin resonance in continuous wave and pulsed modes, we herein present the quantum dynamics of the Mn ion probe in DMAMgF. In the high temperature paraelectric phase, we observe a large distribution of the zero field splitting that is attributed to the high local disorder and further supported by density functional theory computations. In the low temperature ferroelastic phase, a single structure phase is detected and shown to contain two magnetic structures. The complex electron paramagnetic resonance signals were identified by means of the Rabi oscillation method combined with the crystal field kernel density estimation.
二甲基铵甲酸镁,[(CH)NH][Mg(HCOO)] 或 DMAMgF,是一种用于研究高温类钙钛矿型电介质的模型。该化合物在约260 K时呈现有序-无序相变。本文利用连续波和脉冲模式下的多频电子自旋共振,展示了DMAMgF中Mn离子探针的量子动力学。在高温顺电相中,我们观察到零场分裂的大分布,这归因于高局部无序,并得到密度泛函理论计算的进一步支持。在低温铁弹性相中,检测到单一结构相,并显示其包含两种磁结构。通过拉比振荡方法结合晶体场核密度估计,识别出复杂的电子顺磁共振信号。