Effect of Metal−Oxygen Covalent Bonding on the Competition between Jahn−Teller Distortion and Charge Disproportionation in the Perovskites of High-Spin d4Metal Ions LaMnO3and CaFeO3

2002 ◽  
Vol 41 (7) ◽  
pp. 1920-1929 ◽  
Author(s):  
M.-H. Whangbo ◽  
H.-J. Koo ◽  
A. Villesuzanne ◽  
M. Pouchard
Keyword(s):  
High Spin ◽  
Covalent Bonding ◽  
Teller Distortion ◽  
Charge Disproportionation ◽  
Jahn Teller ◽  
Jahn Teller Distortion

scholarly journals Charge disproportionation and nano phase separation in $$\textit{R}\mathrm{SrNiO}_{4}$$

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
H. Guo ◽  
Z. W. Li ◽  
C. F. Chang ◽  
Z. Hu ◽  
C.-Y. Kuo ◽  
...  
Keyword(s):  
Phase Separation ◽  
Phonon Dispersion ◽  
Excitation Spectra ◽  
Teller Distortion ◽  
Charge Disproportionation ◽  
Spin Excitations ◽  
Bond Stretching ◽  
Jahn Teller ◽  
Magnetic Excitation Spectra ◽  
Jahn Teller Distortion

Abstract We have successfully grown centimeter-sized layered $$\textit{R}\mathrm{SrNiO}_{4}$$ R SrNiO 4 single crystals under high oxygen pressures of 120–150 bar by the floating zone technique. This enabled us to perform neutron scattering experiments where we observe close to quarter-integer magnetic peaks below $$\sim 77~\mathrm{K}$$ ∼ 77 K that are accompanied by steep upwards dispersing spin excitations. Within the high-frequency Ni–O bond stretching phonon dispersion, a softening at the propagation vector for a checkerboard modulation can be observed. We were able to simulate the magnetic excitation spectra using a model that includes two essential ingredients, namely checkerboard charge disproportionation and nano phase separation. The results thus suggest that charge disproportionation is preferred instead of a Jahn–Teller distortion even for this layered $$\mathrm{Ni}^{3+}$$ Ni 3 + system.

N-Substituted salicylaldimine complexes of manganese(III). Synthesis, magnetism, and spectra

1969 ◽  
Vol 22 (1) ◽  
pp. 39 ◽  
Author(s):  
A van den Bergen ◽  
KS Murray ◽  
MJ O'Conner ◽  
BO West
Keyword(s):  
High Spin ◽  
Infrared Spectra ◽  
Near Infrared ◽  
Magnetic Behaviour ◽  
Teller Distortion ◽  
Small Deviations ◽  
Near Infrared Spectra ◽  
Jahn Teller ◽  
Jahn Teller Distortion

Complexes of manganese(III) and N-substituted salicylaldimines have been prepared of general formulae Mn(sal-NR)3 and Nn(sal-NR)2X (X = Cl, Br, OAc). The complexes show high-spin magnetic behaviour with small deviations of the susceptibilities from the Curie law. Complexes of the type Mn(salen)X(X = Br, I) have also been studied and these show somewhat larger deviations from Curie behaviour. It is difficult to interpret this Curie-Weiss behaviour with certainty, but it can be explained for the salen derivatives, in particular, in terms of very weak antiferromagnetic interactions. The visible and near-infrared spectra for all the complexes are assigned. A Jahn-Teller splitting of the d-d transition is observed. Comparison of the i.r. spectra of the M(sal)3 derivatives (M = CrIII, MnIII, and FeIII) in the region 700-250 cm-1 has enabled assignments of the v(M-O) modes to be made. The spectra suggest that a Jahn-Teller distortion is operative in the Mn(sal)3 complex.

scholarly journals Unexpected Spin-Crossover and a Low-Pressure Phase Change in an Iron(II)/Dipyrazolylpyridine Complex Exhibiting a High-Spin Jahn–Teller Distortion

2015 ◽  
Vol 54 (13) ◽  
pp. 6319-6330 ◽  
Author(s):  
Laurence J. Kershaw Cook ◽  
Flora L. Thorp-Greenwood ◽  
Tim P. Comyn ◽  
Oscar Cespedes ◽  
Guillaume Chastanet ◽  
...  
Keyword(s):  
Phase Change ◽  
High Spin ◽  
Spin Crossover ◽  
Low Pressure ◽  
Teller Distortion ◽  
Jahn Teller ◽  
Jahn Teller Distortion ◽  
Pressure Phase

Mössbauer-Spektroskopische Untersuchungen an der high/low spin Eisen(II)-Verbindung Cs2FeHFeL(CN)6 / Mössbauer Spectroscopic Investigation of the High/Low Spin Iron(II) Compound Cs2FeHFeL(CN)6

1977 ◽  
Vol 32 (9) ◽  
pp. 992-997 ◽  
Author(s):  
W. D. Griebler ◽  
J. Pebler ◽  
K. Schmidt ◽  
D. Babel
Keyword(s):  
Magnetic Susceptibility ◽  
Low Temperature ◽  
Ir Spectra ◽  
High Spin ◽  
Spectroscopic Investigation ◽  
Ir Absorption ◽  
Teller Distortion ◽  
Jahn Teller ◽  
Jahn Teller Distortion ◽  
High Spin Iron

By Mössbauer spectroscopy the cubic compound CsFe(CN)3, α = 5.208 Å, is shown to contain high and low spin iron(II) in 1:1 proportion independant of temperature 4.2 ≦ T ≦ 600 K. This gives evidence of isomorphism with the elpasolite Cs2MgFe(CN)6. The quadrupol splitting of the high spin iron(II) spectra strongly depends on temperature and vanishes beyond 400 K. This behaviour is interpreted in terms of static Jahn Teller distortion in the low temperature range, also indicated by the splitting of the IR absorption associated with the Fe-N stretching frequency.The data of Mössbauer and IR spectra, as well as of magnetic susceptibility measurements are given and discussed.

Solid solutions of a Jahn-Teller compound in an undistorted host. 2. High-Spin, Six-Coordinate Cr2+ without Jahn-Teller Distortion

1991 ◽  
Vol 598 (1) ◽  
pp. 53-70 ◽  
Author(s):  
F. Albert Cotton ◽  
Larry R. Falvello ◽  
E. Lanelle Ohlhausen ◽  
Carlos A. Murillo ◽  
Jaime F. Quesada
Keyword(s):  
High Spin ◽  
Solid Solutions ◽  
Teller Distortion ◽  
Jahn Teller ◽  
Jahn Teller Distortion
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