The ground state and zero-field splitting of the GdO molecule

Abstract

The X -band ESR spectrum of OdO was obtained in an argon.matrix at 4 OK as a series of 16 fine-structure lines between 0 and 12000 O. Analysis proved that most of these lines were due to off-principal-axis transitions and established the ground state as • I. An accurate fit to the data required the inclusion of a small b~ term (quartic in S,) besides the usual b~ = D term in the spin Hamiltonian. The derived parameters in an argon matrix are gil = 1.990(9).g,= 1.986(5).1 b~1 = ID 1 =0.2078(3) em-I. and 1 b~1 =0.00040(5) em-I. The two strongest lines were also observed in a neon matrix.

Photoelectron Spectra of Gd2O2− and Non-Monotonic Photon-Energy Dependent Variations in Populations of Close-Lying Neutral States

“…Interestingly, based on the calculated relative energies of the neutral states, bands X and b would be assigned to the 17 B1u and 13 B1u states, both of which have parallel alignment of the electron spins in the outer-valence 6s,g and 6s,u orbitals (all other states predicted in this energy range have antiparallel spins). Zero-field splitting in the 9  + state of the GdO (4f 7 6s) state is sub-cm −1 , 38 and tri-nuclear Gd complexes have coupling between the 4f 7 centers on the order of 0.2 cm −1 , 39 which is comparable to a simple classical calculation of the energy difference between Ms = 15 and Ms = 0 FM coupled Gd 4f 7 subshells in the calculated Gd2O2 structure presented here (~1 cm −1 ). However, additional coupling from the unpaired electrons in the outer-valence orbitals may come into play.…”

Photoelectron Spectra of Gd2O2– and Nonmonotonic Photon-Energy-Dependent Variations in Populations of Close-Lying Neutral States

“…Calculations were carried out using the Gaussian suite of electronic structure programs. , Results described above employed the B3LYP/ANO-ECPplusPVTZ model chemistry. The ANO-ECPplusPVTZ incorporates the Stuttgart relativistic small-core atomic natural orbital basis set and effective core potential and corresponding valence basis set for Gd and a Dunning-style correlation consistent basis set for O. , All converged Kohn–Sham determinants were characterized using stability calculations. , Spin-contaminated determinants were treated using spin purification models. − Electron detachments modeled by DFT calculations were characterized using the natural ionization orbital model . Geometry optimizations were carried out using standard techniques, and potential energy surface stationary points were characterized using analytic second-derivative calculations .…”

“…41,42 All converged Kohn−Sham determinants were characterized using stability calculations. 43,44 Spin-contaminated determinants were treated using spin purification models. 23−25 Electron detachments modeled by DFT calculations were characterized using the natural ionization orbital model.…”

Lanthanide Oxides: From Diatomics to High-Spin, Strongly Correlated Homo- and Heterometallic Clusters

“…With its half-filled 4f subshell, the electronic structure of the GdO diatomic molecule has a very low density of electronic states relative to SmO and CeO, as shown schematically in Figure 1. With high spin, no orbital angular momentum, negligible zero field splitting in the 9 Σ − state of GdO, 95 and sub-cm −1 coupling between proximal 4f 7 centers, 96 the Gd 2 O 2 cluster should provide a simpler system for study, both computationally and experimentally. 97 However, the PE spectrum of Gd 2 O 2 − exhibited numerous electronic transitions.…”