MnNiO3 revisited with modern theoretical and experimental methods

Abstract

MnNiO is a strongly correlated transition metal oxide that has recently been investigated theoretically for its potential application as an oxygen-evolution photocatalyst. However, there is no experimental report on critical quantities such as the band gap or bulk modulus. Recent theoretical predictions with standard functionals such as LDA+U and HSE show large discrepancies in the band gaps (about 1.23 eV), depending on the nature of the functional used. Hence there is clearly a need for an accurate quantitative prediction of the band gap to gauge its utility as a photocatalyst. In this work, we present a diffusion quantum Monte Carlo study of the bulk properties of MnNiO and revisit the synthesis and experimental properties of the compound. We predict quasiparticle band gaps of 2.0(5) eV and 3.8(6) eV for the majority and minority spin channels, respectively, and an equilibrium volume of 92.8 Å, which compares well to the experimental value of 94.4 Å. A bulk modulus of 217 GPa is predicted for MnNiO. We rationalize the difficulty for the formation of ordered ilmenite-type structure with specific sites for Ni and Mn to be potentially due to the formation of antisite defects that form during synthesis, which ultimately affects the physical properties of MnNiO.

Quantum Monte Carlo calculations of energy gaps from first principles

“…With backflow, the cost scaling incurs an additional factor of N . QMC has previously been used to study the excited-state properties of silicon, 22,23 diamond, 24,25 hydrogenated silicon clusters, 26 diamondoids, 27 solid hydrogen, 28 solid nitrogen, 29 zinc oxide and selenide, 30 vanadium dioxide, 31 nickel oxide, 32 manganese nickelate, 33 the twodimensional (2D) homogeneous electron gas (HEG), [34][35][36][37] Rydberg states, 38 and various molecular systems. [39][40][41][42][43][44][45][46][47][48] In variational Monte Carlo (VMC), expectation values of observables with respect to explicitly correlated trial wave functions are evaluated using Monte Carlo integration techniques.…”

ReaxFF Force Field Development and Application for Toluene Adsorption on MnMOx (M = Cu, Fe, Ni) Catalysts

“…The fact that this NiMnO 3 behavior may not be a mere consequence of imperfections of our theoretical approach, but rather the feature of this (highly correlated, magnetic) system itself, may be supported by another recent theoretical investigation. 32 …”

Studi In Silico Aktivitas Analog Senyawa Zizyphine dari Bidara Arab (Zizyphus spina-christi) sebagai Antivirus SARS-CoV-2 terhadap Reseptor 3CLpro

“…Optimasi geometri ini bertujuan untuk memperoleh konformasi struktur yang stabil dan sesuai dengan keadaan aslinya menggunakan metode Density Functional Theory (DFT) dengan potensial fungsional teori B3LYP pada basis set 3-21G. Senyawa analog Zizyphine yang telah dilakukan optimasi geometri kemudian dimodifikasi data muatan parsial untuk digunakan sebagai input dalam simulasi docking (Dzubak et al, 2017;Giannozzi et al, 2020).…”