Magnetic circular x-ray dichroism in transverse geometry: Importance of noncollinear ground state moments

AbstractMass-selected V and Fe monomers, as well as the heterodimer $${\text{Fe}}_1{\text{V}}_1$$ Fe 1 V 1 , were deposited on a Cu(001) surface. Their electronic and magnetic properties were investigated via X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) spectroscopy. Anisotropies in the magnetic moments of the deposited species could be examined by means of angle resolving XMCD, i.e. changing the X-ray angle of incidence. A weak adatom-substrate-coupling was found for both elements and, using group theoretical arguments, the ground state symmetries of the adatoms were determined. For the dimer, a switching from antiparallel to parallel orientation of the respective magnetic moments was observed. We show that this is due to the existence of a noncollinear spin-flop phase in the deposited dimers, which could be observed for the first time in such a small system. Making use of the two magnetic sublattices model, we were able to find the relative orientations for the dimer magnetic moments for different incidence angles.

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Experimental evidence of the ferrimagnetic ground state of Sr 2 FeMoO 6 probed by X-ray magnetic circular dichroism

EPL (Europhysics Letters) ◽

10.1209/epl/i2002-00262-4 ◽

2002 ◽

Vol 60 (4) ◽

pp. 608-614 ◽

Cited By ~ 67

Author(s):

M Besse ◽

V Cros ◽

A Barthélémy ◽

H Jaffrès ◽

J Vogel ◽

...

Keyword(s):

Circular Dichroism ◽

Experimental Evidence ◽

Ground State ◽

Magnetic Circular Dichroism ◽

X Ray ◽

Circular Dichroïsm

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Reactions of (η5-C9H7)Rh(η2-C2H4)2 with quinones: molecular structure of [(η5-C9H7)Rh(2,3,5,6-C6O2(CH3)4)]

Canadian Journal of Chemistry ◽

10.1139/v98-228 ◽

1999 ◽

Vol 77 (2) ◽

pp. 199-204

Author(s):

Stephen A Westcott ◽

Nicholas J Taylor ◽

Todd B Marder

Keyword(s):

Molecular Structure ◽

Least Squares ◽

Ground State ◽

Slip Parameter ◽

X Ray Diffraction ◽

X Ray ◽

A Value ◽

Hinge Angle

Reactions of (η5-C9H7)Rh(η2-C2H4)2 (1) with quinones were investigated. Substitution of the labile ethylene ligands was observed upon addition of either duroquinone (2,3,5,6-tetramethyl-1,4-benzoquinone) or 1,4-benzoquinone to complex 1. The molecular structure of neutral (η5-C9H7)Rh(2,3,5,6-C6O2(CH3)4) (3), determined by X-ray diffraction, shows that the duroquinone ligand lies in a plane nearly parallel to the indenyl group. The carbonyl moieties of duroquinone lie in a plane incorporating Rh, C2, and the midpoint between C3a and C7a of the indenyl ring. The slip parameter (Δ= d(average Rh-C3a,7a) -d(average Rh-C1,3)) was calculated to be 0.112(2) Å; whereas a value of ca. 0.05 Å had been obtained previously from film data. Values for the hinge angle (HA = angle between normals to the least-squares planes defined by C1, C2, C3 and C1, C7a, C3a, C3) and fold angle (FA = angle between normals to the least-squares planes defined by C1, C2, C3 and C3a, C4, C5, C7, C7a) are 7.2° and 4.0°, respectively.Key words: indenyl, rhodium, quinones, ring-slippage, ground-state distortion.

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Comparative Spectroscopic Studies on Luminescence Performance of Er3+ Doped Tellurite Glass Embedded with Different Nanoparticles (Ag Co and Fe) at 0.55 μm Emission

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.317.81 ◽

2021 ◽

Vol 317 ◽

pp. 81-86

Author(s):

Syariffah Nurathirah Syed Yaacob ◽

Md. Rahim Sahar ◽

Faizani Mohd Noor ◽

Nur Liyana Amiar Rodin ◽

Siti Khadijah Mohd Zain ◽

...

Keyword(s):

Energy Transfer ◽

Ground State ◽

Tellurite Glass ◽

Spectroscopic Studies ◽

The Other ◽

X Ray Diffraction ◽

Melt Quenching ◽

X Ray ◽

Doped Glass ◽

Luminescence Performance

The spectroscopic performance of Er3+ doped glass at 0.55 mm emission contain different nanoparticles NPs have been comparatively evaluated. Glass containing 1.0 mol % of Er3+ doped with different NPs (Ag, Co and Fe ) have been prepared using melt quenching technique. X-ray diffraction analysis reveals the all the prepared samples are amorphous. The UV-Vis absorption spectra of all glasses show several prominent peaks at 525 nm, 660 nm, 801nm, 982 nm and 959 nm due to transition from ground state 4I15/2 to different excited of 2H11/2, 4F9/2, 4I9/2, 4I11/2, and 4I13/2. The emission of Er3+ at 0.55 mm for glass contain Ag NP shows significant enhancement about 3 folds up to 0.6 mol%. On the other hand, the emission of Er3+ at 0.55 mm for glass containing Fe NPs and Co NPs intensely quench probably due to the energy-transfer from Er3+ ion to NPs and magnetic contributions.

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Resonant X-ray scattering as a probe of the valence and magnetic ground state and excitations in Pr0.6Ca0.4MnO3

Physica B Condensed Matter ◽

10.1016/j.physb.2003.11.008 ◽

2004 ◽

Vol 345 (1-4) ◽

pp. 6-10 ◽

Cited By ~ 1

Author(s):

S. Grenier ◽

K.J. Thomas ◽

Young-June Kim ◽

J.P. Hill ◽

Doon Gibbs ◽

...

Keyword(s):

Ground State ◽

Magnetic Ground State ◽

X Ray ◽

X Ray Scattering ◽

Ray Scattering

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X-ray laser lines in nickel-like erbium

Canadian Journal of Physics ◽

10.1139/cjp-2015-0438 ◽

2016 ◽

Vol 94 (8) ◽

pp. 705-711

Author(s):

Wessameldin S. Abdelaziz

Keyword(s):

Ionization Potential ◽

Excited States ◽

Ground State ◽

Energy Levels ◽

Single Electron ◽

Electron Densities ◽

X Ray ◽

Electron Excited States

Energy levels of 249 excited levels in nickel-like erbium are calculated using the 3s23p63d10 as a ground state and the single electron excited states from n = 3 to n = 4, 5 orbitals, calculations have been performed using FAC code (Gu. Astrophys. J. 582, 1241 (2003). doi:10.1086/344745 ). The populations are calculated over electron densities from 1020 to 1023 cm−3 and electron temperatures 1/2, 3/4 of the ionization potential of Ni-like Er. The gain coefficients of the transitions are calculated.

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A single crystal, linearly polarized Fe 2p X-ray absorption study of gillespite

Mineralogical Magazine ◽

10.1180/002646198547477 ◽

1998 ◽

Vol 62 (1) ◽

pp. 65-75 ◽

Cited By ~ 7

Author(s):

P. F. Schofield ◽

G. van der Laan ◽

C. M. B. Henderson ◽

G. Cressey

Keyword(s):

Single Crystal ◽

Ground State ◽

Branching Ratio ◽

Linear Dichroism ◽

Electronic Charge ◽

Magic Angle ◽

X Rays ◽

X Ray ◽

Peak Structure ◽

X Ray Absorption

AbstractThe Fe 2p X-ray absorption spectra of single crystal gillespite, BaFeSi4O10, show a strong linear dichroism, i.e. a large difference in the absorption when measured with the polarization of the X-rays either parallel or perpendicular to the plane of the FeO4 group. The isotropic spectrum, obtained from measurement at the ‘magic angle’, and the polarization dependent spectra have been compared to atomic multiplet calculations and show an excellent agreement with theory. Analysis of the branching ratio, the linear dichroism, and the detailed peak structure confirms that the 5A1 level is the ground state at room temperature and pressure. The 5B2 level is sufficiently low in energy that a distortion of the electronic charge density, induced by increased pressure, may result in a 5B2 ground state.

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Preparation, and complexes with nickel(II) and copper(II), of a diazepane amine alcohol. The structure of [4,4-dimethyl-7-(5,5,7-trimethyl-1,4-diazepan-1-yl)-5-azaheptan-2-ol]nickel(II) perchlorate

Australian Journal of Chemistry ◽

10.1071/ch9831341 ◽

1983 ◽

Vol 36 (7) ◽

pp. 1341 ◽

Cited By ~ 4

Author(s):

KR Morgan ◽

GJ Gainsford ◽

NF Curtis

Keyword(s):

Ground State ◽

Coordination Compounds ◽

Major Product ◽

Boat Conformation ◽

Singlet Ground State ◽

X Ray Diffraction ◽

X Ray ◽

Oxygen Donor ◽

Square Planar ◽

Coordination Plane

Reduction of 4,4,12,12-tetramethyl-5,8,11-triazapentadecane-2,14-dione diperchlorate by sodium borohydride yields as the major product one isomer of 4,4-dimethyl-7-(5,5,7-trimethyl-1,2-diazepam 1-yl)-5-azaheptan-2-ol, pyaz. The coordination compounds [M(pyaz)] (ClO4), and [Ni(pyaz)(NCS)] CNS (M = NiII, CuII) were prepared, the latter being assigned five-coordinate structures. The structure of singlet ground state [Ni(pyaz)] (ClO4)2 was determined by X-ray diffraction [space group P212121, Z 4, a 1450.8(2), b 1522.2(1), c 1048.5(1) pm, R 0.0675, Rw 0.0768 for 2461 reflections]. The compound has a square-planar coordination arrangement, with the three nitrogen and the oxygen donor atoms of the pyaz ligand approximately coplanar [Ni-O 190.0(6) pm; Ni-N 192.8(6), 189.2(6), 189.2(6) pm in sequence N(5) of chain, N(l), N(4) of diazepane]. The diazepane ring adopts a boat conformation. One side of the nickel(II) coordination plane is sterically crowded by the presence of two axial methyl substituents. The ligand has two non-equivalent chiral centres (C(14) of the diazepane ring and C(2) of the amine alcohol chain), both present in the R configuration in the crystal studied. The three nitrogen atoms, which became chiral centres upon coordination, are present in the S configuration for two diazepane nitrogen atoms and in the R configuration for the 5-aza chain nitrogen.

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