First-Principles Chemical Bonding Study of Manganese Carbodiimide, MnNCN, As Compared to Manganese Oxide, MnO

Abstract

We have performed an in-depth study of the chemical bonding in manganese oxide (MnO) and carbodiimide (MnNCN) from correlated spin-polarized density functional calculations. The chemical-bonding data were produced using the LOBSTER package, which has recently been enabled to process PAW-based output from Quantum ESPRESSO. Our results show that the ground states of MnO and MnNCN are similar, namely, antiferromagnetic structures whose axes are the MnO cubic [111] and the MnNCN hexagonal [001] axes, in agreement with experimental results. The results also evidence MnNCN being more covalent than MnO, in harmony with chemical intuition and spectroscopic data. In addition, the crystal orbital Hamilton population (COHP) analysis evidences that adopting the ground-state magnetic structures by MnO and MnNCN makes the cation-anion bonds optimized and annihilates obvious instability issues, that is, the existence of antibonding states in the vicinity of the Fermi level. We also detail the interactions involved in the systems using the recently introduced density-of-energy analysis and by partitioning the total and band-structure energies. While it is trivial that the total energy points toward the true magnetic ground state taken, the COHP integral of the metal-nonmetal bond is also capable of correctly delivering that particular information.

Synthesis, Crystal Structure, and Chemical-Bonding Analysis of BaZn(NCN)2

“…This comparison reveals striking similarities between the two phases, with Zn-N and A-N interactions of antibonding character in the vicinity of the Fermi level even though the network connectivities and A-site coordination environments are quite different. Similar, energetically disadvantageous M-N bonding interactions in the proximity of ε F have recently also been witnessed for the case of MnNCN and may be looked upon as a typical fingerprint of the (late) 3d-metal carbodiimides [28]. Future work will look to extend this emerging AM(NCN) 2 family by accessing analogues featuring divalent transition-metal cations at the tetrahedral site.…”

Structural and electronic properties of Mo6S3I6 nanowires by newly proposed theoretical compositional ordering

“…Previous studies with partial DOS have elucidated the electronic structures of these materials, however, the nature of states at the Fermi level have not been characterized by chemical-bonding analysis 31,32 . Using crystal orbital Hamilton population (COHP) curves implemented in the Local-Orbital Basis Suite Towards Electronic-Structure Reconstruction (LOBSTER) package 31,33 , we obtained the information about bonding and antibonding contributions of our targeted Mo 6 S 3 I 6 nanowires by re-extracting the atom-resolved information from delocalized plane-wave basis sets.…”

“…6(a). The diagram of COHP reveals a stabilizing or destabilizing energy criterion that converts the DOS into both negative for bonding and positive for antibonding values, in contrast to the conventional DOS, which yields the number of electrons in the system 32 . As shown in Fig.…”

“…The Mo-4d, S-3p, and I-5p electrons are considered to be valence electrons not only for the pDOS but also for the calculation of crystal orbital Hamilton population, which is employed for the analysis of bonding and antibonding orbital energy and the interaction between specific atoms. In addition to VASP, Xcrysden 43,44 , wxDragon 45 and LOBSTER 31,32 were employed for visualizing the calculation results.…”

Reversible High Capacity and Reaction Mechanism of Cr2(NCN)3 Negative Electrodes for Li‐Ion Batteries

“…Not too surprisingly, we obtained a cell voltage of 1.6 V (0.9 V) for Cr 2 (NCN) 3 , which yields a voltage error of 0.5 V (0.2 V) within the Perdew-Burke-Ernzerhof (PBE) (PBE þ U ) method, as compared with the experimental 1.1 V. It indicates that the U correction gives a better coulombic interaction and improves the electrochemical (voltage) data accuracy. [58] Therefore, in the following simulations, we used the PBE þ U for reasons of accuracy.…”