Disclosing the Structural, Electronic, Magnetic, and Morphological Properties of CuMnO₂: A Unified Experimental and Theoretical Approach

Abstract

Precise control of the overall performance for solid-state materials is associated with morphological modulations which provide an alternative way to the rational design based on understanding the corresponding electronic structures of the exposed surfaces. Experimental and theoretical efforts were combined herein to elucidate the structural–property relationship of CuMnO2 nanoparticles from different morphologies. The microwave-assisted hydrothermal method was employed to synthesize these crystals with different morphologies, while first-principle quantum mechanical calculations were performed at the DFT level to obtain the structural, electronic, and magnetic properties of CuMnO2 surfaces. Our structural results have confirmed a monoclinic structure for crednerite-type CuMnO2 nanoparticles described by the Jahn–Teller-distorted octahedral [MnO6] clusters, which are connected by linear 2-fold [CuO2]. FE-SEM images combined with Wulff construction analyses indicated that CuMnO2 nanoparticles adopt a hexagonal nanoplate-like morphology which can enclose a major extent of the (100) surface with contributions from (101), (110), and (111) surfaces. Electronic structure and magnetic characterizations were discussed by the role of the corresponding electronic states of exposed surfaces which control the energy-level band diagram and spin density distribution. These results extend our fundamental understanding of the atomic processes which underpin the morphological modulations of the CuMnO2 material, thus creating a new path to obtain selected nanoparticles with desirable properties which optimize their applications.

Atomistic Perspective on the Intrinsic White-Light Photoluminescence of Rare-Earth Free MgMoO4 Nanoparticles

“…The equilibrium shape of a crystal and its modulations can be calculated from the Wulff construction, which minimizes the total surface free energy at a fixed volume, providing a simple relationship between the surface energy ( E surf ) of a ( hkl ) plane and its distance from the crystallite center in the normal direction . Therefore, combining the calculated E surf values for different MgMoO 4 surfaces enabled investigation of the morphological properties of MgMoO 4 nanoparticles and comparison of them with the experimental findings by following previous studies and the references therein. − …”

Role of Surfaces in the Magnetic and Ozone Gas-Sensing Properties of ZnFe2O4 Nanoparticles: Theoretical and Experimental Insights

“…Regarding the magnetic properties of the ZnFe 2 O 4 surface, the magnetization index ( M ) from the calculated spin density ( D μ ) index of a given surface was calculated following the procedure previously reported by our group − …”

Unconventional Disorder by Femtosecond Laser Irradiation in Fe2O3

“…The advance of the simulation of the magnetic properties in surfaces progressed in the last years. − Thus, to deeply investigate the magnetic properties of the α-Fe 2 O 3 and ε-Fe 2 O 3 morphologies, it is essential to know the magnetization index ( M ) in each ( hkl ) Miller index. To reach this goal, we applied a recent and innovative method. − In the first stage, the magnetization index ( D μ ) of a given ( hk l) surface (eq ) is calculated, where D μ is connected to the magnetic moment (μ B ) in a particular ( hkl ) surface per unit cell area ( A ). Posteriorly, M is calculated from eq , where the M value represents the combination of all contributions of each surface plane to the morphology, c ( hkl ) , and the corresponding D μ . …”