The electron-spin magnetic moments (g factors) of O3−, O3Li, and O3Na: An ab initio study

Abstract

Articles you may be interested inAb initio multireference configuration-interaction theoretical study on the low-lying spin states in binuclear transition-metal complex: Magnetic exchange of [ ( NH 3 ) 5 Cr ( μ -OH ) Cr ( NH 3 ) 5 ] 5 + and [ Cl 3 FeOFeCl 3 ] 2 − Ab initio study of the gas-phase structure and electronic properties of M-CH 3 ( M=Li,Na ) and M-CCH ( M=Li, Na,K ): A combined post-Hartree-Fock and density functional theory study Accurate ab initio near-equilibrium potential energy and dipole moment functions of the X 2 B 1 and first excited 2 A 2 electronic states of OClO and OBrO as parametrized by the g factors, are studied at the uncorrelated restricted open Hartree-Fock ͑ROHF͒ and correlated multireference configuration interaction ͑MRCI͒ ab initio levels. The present method, which uses a perturbative approach complete to second order, is based on a Breit-Pauli Hamiltonian. The calculated ⌬g values, with ⌬gϭgϪg e , are very similar for all three species, confirming that the O 3 Ϫ moiety is retained in the ozonides O 3 M. In the standard C 2v notation, ⌬g yy Ͼ⌬g zz ӷ͉⌬g xx ͉. The perpendicular component ⌬g xx is small and negative, while the in-plane components ⌬g yy and ⌬g zz are large and positive. The MRCI results for ⌬g xx , ⌬g yy , ⌬g zz ͑in ppm͒ are: Ϫ475, 16 673, 10 121 for O 3 Ϫ ; Ϫ679, 13 894, 9308 for O 3 Li; and Ϫ494, 12 298, 8690 for O 3 Na. The ROHF values of ⌬g yy and ⌬g zz are smaller than the MRCI data, due to a general overestimation of the excitation energies. The MRCI ⌬g values for isolated O 3Ϫ reproduce the experimental results for O 3 Ϫ trapped in crystals or adsorbed on MgO surfaces ͑in ppm, Ϫ500-1200 for ⌬g xx , 12 400-16 400 for ⌬g yy , and 6900-10 000 for ⌬g zz ). For O 3 Na, the experimental ⌬g xx , ⌬g yy , ⌬g zz data ͑Ϫ100, 14 200, 9800 ppm͒ are again satisfactorily described by our correlated results. No experimental g shifts are available for O 3 Li. In all systems studied here, the ⌬g xx component is dictated by first-order terms ͑ground state expectation values͒; ⌬g yy is governed by the second-order magnetic coupling between X 2 B 1 and 1 2 A 1 ͓electron excitation from the highest a 1 molecular orbital ͑MO͒ into the b 1 (*) singly occupied MO͔; and ⌬g zz , by the coupling with two 2 B 2 states ͑excitations from the two highest b 2 MOs into *).

Ozonide ions on the surface of MgO nanocrystals

“…Although the g tensor of the O À 3 species reflects the properties of the radical itself rather than the electronic structure of the adsorption site [14,42], a clear correlation between specific surface O -species and their derived O À 3 radicals was observed. Moreover, adsorption energies associated with ozonide formation (equation 1) were determined experimentally and compared with results from theoretical calculations.…”

Comparing electron-sping-tensor results of first-row radicals with those of higher rows

“…In recent years, the g shifts of small radicals (mostly from the first row) have been calculated in our laboratory, e.g., MgF 10; NO 2 , H 2 O + , CO + 11; MX 2 (X 2 C 2 , N 2 , O 2 , F 2 ) 17, 18; F, Cl and related V k centers 18; MO 3 41; H 2 CO⋅Na 42. The calculations were carried out using second‐order perturbation theory over a Breit–Pauli Hamiltonian, in conjunction with correlated (MRCI) wave functions.…”

Calculation of EPR g Tensors for Transition‐Metal Complexes Based on Multiconfigurational Perturbation Theory (CASPT2)

“…All methods produce varying results for Dg yy , thus demonstrating how difficult it is to calculate this particular value. [1] and the MRDCI results by Bruna and Grein [39] (Dg xx = 16 673 ppm, Dg yy = À475 ppm, Dg zz = 10 121 ppm). All methods give a negative Dg yy value, while the experimental value is positive.…”