The effect of a magnetic field on the high spin to or from low-spin transitions in ferrous and ferric compounds

The HS ⇌ LS transition in ferric dithiocarbamates in a number of solvents has been investigated using NMR and is interpreted in terms of preferential solvation or second co-ordination sphere reorganisation effects. These studies clearly demonstrate that neglect of pseudo contact shifts can lead to erroneous conclusions about the spin delocalisation mechanisms. The spin derealization in these systems is by direct σ-delocalization along the alkyl chain. The As values of 2T2 and 6A1 states have the same sign.

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Behavior of high-spin molecules and rare-earth ions in a bifrequency AC magnetic field

Journal of Magnetism and Magnetic Materials ◽

10.1016/s0304-8853(02)00579-6 ◽

2002 ◽

Vol 251 (2) ◽

pp. 215-219 ◽

Cited By ~ 4

Author(s):

I.D Tokman ◽

G.A Vugalter

Keyword(s):

Magnetic Field ◽

Rare Earth ◽

High Spin ◽

Rare Earth Ions ◽

Ac Magnetic Field

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Electronic Structures of Tetragonal Sixfold-Coordinated Iron (III) Complexes with High-Spin—Intermediate-Spin Transitions

physica status solidi (b) ◽

10.1002/pssb.2221910214 ◽

1995 ◽

Vol 191 (2) ◽

pp. 395-400 ◽

Cited By ~ 4

Author(s):

Xiao-Yu Kuang ◽

Irène Morgenstern-Badarau

Keyword(s):

High Spin ◽

Electronic Structures ◽

Intermediate Spin ◽

Spin Transitions

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Temperature-dependent magnetic moments of Fe(III) complexes with high-spin–low-spin transitions

Physical Review B ◽

10.1103/physrevb.47.5455 ◽

1993 ◽

Vol 47 (9) ◽

pp. 5455-5458 ◽

Cited By ~ 5

Author(s):

Kuang Xiao-Yu ◽

Irène Morgenstern-Badarau ◽

Isabelle Malfant

Keyword(s):

High Spin ◽

Magnetic Moments ◽

Temperature Dependent ◽

Spin Transitions

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Pyrochlores. IV. Crystallographic and Mössbauer studies of A2FeSbO7 pyrochlores

Canadian Journal of Chemistry ◽

10.1139/v68-635 ◽

1968 ◽

Vol 46 (24) ◽

pp. 3829-3832 ◽

Cited By ~ 34

Author(s):

Osvald Knop ◽

François Brisse ◽

R. E. Meads ◽

J. Bainbridge

Keyword(s):

Magnetic Field ◽

Oxygen Atom ◽

Isomer Shift ◽

Quadrupole Splitting ◽

High Spin ◽

Room Temperature ◽

Magnetic Order ◽

Standard Procedure ◽

Hyperfine Magnetic Field ◽

Mössbauer Studies

The lattice parameters and the quadrupole splittings of the room-temperature Mössbauer spectra of the cubic A2FeSbO7 pyrochlores (A = Sm, Eu, Gd, Tb, Y, Er, Lu) have been found to vary linearly with the Templeton–Dauben radii of the A3+ ions. The variation of the quadrupole splitting can be correlated with the positional parameter of the majority oxygen atom, x(O2), which determines the degree of distortion of the BO6 octahedron in cubic A2B2O7 pyrochlores. An increase of 0.1 Å in r(A3+) corresponds to a decrease of ca. 0.20 mm/s in the quadrupole splitting in the A2FeSbO7 series, and to an estimated increase of ca. 0.005 in x(O2). The isomer shift and quadrupole splitting at room temperature are typical of Fe3+(high spin) in octahedral coordination of relatively high distortion. Y2FeSbO7 at 4.2°K was found to exhibit magnetic order with a hyperfine magnetic field of approximately 400 kOe. An attempt to prepare a cubic La2FeSbO7, pyrochlore by the standard procedure was not successful.

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