Structural, magnetic, magneto-transport properties and Bean–Rodbell model simulation of disorder effects in Cr³⁺ substituted La_0.67Ba_0.33MnO₃ nanocrystalline synthesized by modified Pechini method

Abstract

Nanocrystalline powders (around 100 nm) of La0.67Ba0.33CrxMn1−xO3 (x ≤ 0.17) perovskites have been synthesized by the sol–gel based Pechini method at low temperatures.

Pr3+ doping at the A-site of La0.67Ba0.33MnO3 nanocrystalline material: assessment of the relationship between structural and physical properties and Bean–Rodbell model simulation of disorder effects

“…The parameters η , J , T 0 , and its FWMH, are tuned in order to provide a best fit to experimental curves such as M vs. H , M vs. T , and, H / M vs. M 2 . 18 Fig. 5 shows examples data for (La 1− x Pr x ) 0.67 Ba 0.33 MnO 3 ( x = 0.15, and 0.22) and best fit curves.…”

“…Such a difference in (m eff ) values may be ascribed to the appearance of short-range FM interactions in the paramagnetic state (above T C ), which is commonly observed in manganites. 18,20,43 3.…”

“…In order to study the nature of the magnetic transition, we have applied the Bean-Rodbell model to our magnetization data for (La 1Àx Pr x ) 0.67 Ba 0.33 MnO 3 (x ¼ 0.15, and 0.22). Manganite materials 18,44 with second-and rst-order phase transition have been adequately interpreted using this model, which describes in particular the magnetovolume interactions. 45 The model considers the dependence of the exchange interaction on the interatomic distance.…”

“…Pechini method has been used successfully to produce high-quality specimens due to these potential advantages such as better homogeneities, lower processing temperatures, short annealing times, high purity of materials and improved material properties. 18 La 0.67 Ba 0.33 MnO 3 (LBMO) has been one of the most appealing manganites, and in its bulk form, it has been found to exhibit by Mn-site substitution (B-site) in perovskite oxides, with other transition metal ions, 8,17,18 a second order of magnetic phase transition. Besides, past studies on substituting praseodymium at the A-site of manganite are focused on polycrystalline ceramics.…”

Influence of the starting temperature of calorimetric measurements on the accuracy of determined magnetocaloric effect

“…In this work, we extend the previous analysis to materials with a first order phase transition by using the Bean-Rodbell model [17]. It has previously been shown that this model can be applied to describe the MC response of different materials with a FOPT [18,19]. Specifically, the modification of a parameter ( ) can simulate magnetic phase transitions of either first or second order type.…”