This study was conducted to investigate the use of cubic LaMnO3 nano-perovskite as a green catalyst for the degradation of an aqueous solution of methyl orange under different conditions. Nanoscale cubic lanthanum manganite with the particle size of ~20 nm was successfully synthesized via citrate sol-gel method. The sample was characterized using the FT-IR and UV-Vis spectroscopy, XRD, SEM, and...

Phase separation is a crucial ingredient of the physics of manganites; however, the role of mixed phases in the development of the colossal magnetoresistance (CMR) phenomenon still needs to be clarified. We report the realization of CMR in a single-valent LaMnO3 manganite. We found that the insulator-to-metal transition at 32 GPa is well described using the percolation theory. Pressure induces ...

Using the Mott–Littleton approach we examine the energies of a number of fundamental optical transitions, as well as those involving self-trapped holes of Mn and O in LaMnO3 lattice. The reasonable agreement with the experiment of our predicted energies, linewidths and oscillator strengths leads us to plausible assignments of the optical bands observed. We deduce that the optical band near 5 eV...

We report predominantly zero field muon spin relaxation measurements in a series of Ca-doped LaMnO3 compounds which includes the colossal magnetoresistive manganites. Our principal result is a systematic study of the spin-lattice relaxation rates 1/T1 and magnetic order parameters in the series La1−xCaxMnO3, x = 0.0, 0.06, 0.18, 0.33, 0.67 and 1.0. In LaMnO3 and CaMnO3 we find very narrow criti...

We study the recently observed orbital excitations, orbitons, and treat electron-electron correlations and lattice dynamics on an equal footing. It is shown that the orbiton energy and dispersion are determined by both correlations and lattice vibrations. The electron-phonon coupling causes satellite structures in the orbiton spectral function and the elementary excitations of the system are mi...

Atomically sharp oxide heterostructures exhibit a range of novel physical phenomena that are absent in the parent compounds. A prominent example is the appearance of highly conducting and superconducting states at the interface between LaAlO3 and SrTiO3. Here we report an emergent phenomenon at the LaMnO3/SrTiO3 interface where an antiferromagnetic Mott insulator abruptly transforms into a nano...

The standard Gibbs energy of formation of LaMnO3 has been measured in the temperature range from 900 to 1400 K using a solid-state cell incorporating a buffer electrode. The oxygen potential corresponding to the three-phase mixture MnO 1 La2O3 1 LaMnO3 has been measured using pure oxygen gas at 0.1 MPa as the reference electrode, and yttria-stabilized zirconia as the solid electrolyte. The buff...

Single-phase oxygen stoichiometric LaMnO3 and doped La0.8A0.2MnO3 (A = Ca, Sr, Ba) perovskites have been prepared by a simple one-step auto-combustion method. Cation-deficient LaMnO3+δ La0.8A0.2MnO3+δ were obtained calcination of the former samples in air at 750 °C. The characterized X-ray powder diffraction, photoelectron spectroscopy, temperature-programmed reduction, desorption, N2 physisorp...

Using X-ray absorption spectroscopy (XAS), we studied the local structure in LaMnO3 under applied pressure across and well above the insulator-to-metal (IM) transition. A hysteretic behavior points to the coexistence of two phases within a large pressure range (7 to 25GPa). The ambient phase with highly Jahn-Teller (JT) distorted MnO6 octahedra is progressively substituted by a new phase with l...