A comparative study of small 3d-metal oxide (FeO)_n, (CoO)_n, and (NiO)_n clusters

Abstract

Geometrical and electronic structures of the 3d-metal oxide clusters (FeO), (CoO), and (NiO) are computed using density functional theory with the generalized gradient approximation in the range of 1 ≤ n ≤ 10. It is found that the cluster geometries are similar in the (FeO) and (CoO) series but noticeably different in the (NiO) series for several values of n. All of the lowest total energy states are found to possess relatively small spin multiplicities and are either antiferromagnetic or ferrimagnetic except for the states of (NiO), (NiO), (NiO), and (NiO), which are ferromagnetic. The computed polarizabilities per atom undergo a steep decrease when compared to the atomic values of the MO monomers (M = Fe, Co, and Ni). Surprisingly, the polarizability does not strongly depend on either M or n in all the considered series when n varies from 3 to 10. The binding energies per atom are the largest in the (FeO) series, followed by the binding energies of (CoO) and (NiO).

Small binary iron‐carbon clusters with persistent high magnetic moments. A theoretical characterization

“…In consequence, binary iron‐carbon clusters have become an object of study thanks to the progress in theoretical methods . Several methodologies, most of them within the density functional theory (DFT), have been used for many years to study clusters made of pure iron, iron oxide, and iron‐carbon . Recently, Zheng et al did an exhaustive and chronological review of the methodologies used during the last two decades for neutral binary iron‐carbon clusters.…”

Orbital-dependent photodynamics of strongly correlated nickel oxide clusters

“…Calculations were performed using the 6-311G+* basis set, namely (15s11p6d1f/10s7p4d1f) for Ni and (12s6p1d/ 5s4p1d) for O atoms. The initial choices for the atomic coordinates for the geometry optimizations were obtained from previous studies 22,23 and then optimized in Gaussian16 24 while considering a variety of spin states (up to 2S + 1 = 13). Our calculated structures of nickel oxide clusters are in agreement with previous calculations, and show that (NiO) 2À5 clusters all form planar ring structures.…”

Co13O8—metalloxocubes: a new class of perovskite-like neutral clusters with cubic aromaticity

“…Gutsev et al. [ 24 ] performed an systematic investigation on small (FeO) n , (CoO) n and (NiO) n clusters, where the 3d-metal oxides preferred oxygen bridge-linked Co(III) sites. Riley and coworkers [ 25 ] studied the reactions of cobalt clusters with water and ammonia, and found addition reactions to be dominant channels.…”