Anomalous spin Hamiltonian parameters of pseudotetrahedral copper(II) complexes. ESR spectra of copper(II)-doped dichlorobis(triphenylphosphine oxide)zinc(II)

In this report, Fe 3+ impurity ions present in green sapphire ( Al 2 O 3) were studied experimentally, by heating a light green sapphire in flowing oxygen atmosphere for 12 h from 1200, 1300, 1400, 1500 and 1600°C, respectively. Electron spin resonance (ESR) spectra in X-band (~9.45 GHz ) were recorded by mounting the crystal with the c-axis perpendicular (θ = 90°) to the magnetic field direction. The spectra were recorded and simulated by a numerical diagonalization of spin Hamiltonian matrix in the range from 0 to 180 degrees for every 15 degrees of rotation angle (φ). In our case, only the last two sets of peaks strongly depend on the rotation angle (φ), and each exhibits C 3 symmetry due to two magnetically inequivalent Fe 3+ sites in the corundum structure. For polycrystalline ESR spectra, seven main Fe 3+ ESR absorption peaks occur at the resonance magnetic fields of 100.20, 310.24, 486.80, 525.00, 550.60, 761.00 and 777.00 mT respectively. Specifically, ESR signals show that the number of paramagnetic Fe 3+ ions increase roughly linearly with the heat treating temperature, having the [Formula: see text] ratio ~1.41 at 1600°C.

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REDUCTION BY HYDROGEN OF VANADIUM IN PHOSPHATE AND VANADATE LEAD APATITES: AN ESR STUDY

Modern Physics Letters B ◽

10.1142/s0217984907013742 ◽

2007 ◽

Vol 21 (22) ◽

pp. 1489-1500 ◽

Cited By ~ 4

Author(s):

M. IKRAM ◽

H. AHMED ◽

PIETRO MENDES ◽

F. A. MIR ◽

A. BASHIR ◽

...

Keyword(s):

Solid Solution ◽

Computer Simulations ◽

Esr Spectroscopy ◽

Esr Spectra ◽

Hydrogen Gas ◽

Charge Carriers ◽

Spin Hamiltonian ◽

Powder Spectrum ◽

Hamiltonian Parameters ◽

Vanadium Ions

A solid solution of phosphate and vanadate lead apatites Pb 10( PO 4)6-x( VO 4)x( OH )2 (x = 0.5, 1.0, 2.0, 3.0, and 6.0) were reduced with hydrogen gas at temperature 300°C for one hour. All these compounds were investigated by XRD and ESR spectroscopy. Only one reduced oxidation state, V 4+, was detected. Two types of species-like isolated vanadium (+ 4) and clusters of V 4+ were observed. The EPR powder spectrum computer simulations were performed using the program Simfonia from Bruker. Spin Hamiltonian parameters were also calculated. As the concentrations of vanadium ions increase to 2.0, the intensity of the ESR lines increases, and x = 3.0 the intensity of the ESR line decreases sharply. After this concentration, i.e. x > 3.0, there is again an increase in the intensity. The variation of the line shape and intensity of the ESR spectra can be attributed to increases in the hopping rate of the charge carriers (polarons) in different apatite compositions.

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THE SPIN HAMILTONIAN PARAMETERS CALCULATION OF 14N AND 15N IN NATURAL TYPE I DIAMOND

International Journal of Modern Physics B ◽

10.1142/s0217979208050498 ◽

2008 ◽

Vol 22 (25n26) ◽

pp. 4740-4748 ◽

Cited By ~ 2

Author(s):

CHITTRA KEDKAEW ◽

PICHET LIMSUWAN ◽

KANPHOT THONGCHAM ◽

SIWAPORN MEEJOO

Keyword(s):

Natural Diamond ◽

Microwave Frequency ◽

Esr Spectra ◽

Type I ◽

Spin Hamiltonian ◽

X Band ◽

Natural Type ◽

Hamiltonian Parameters ◽

Parameters Calculation ◽

Resonance Magnetic Field

The main purpose of this work is to present the ESR spectra and calculate the spin Hamiltonian parameters of 14 N and 15 N impurities in natural diamond. The ESR spectra of diamond crystal were measured on ESR spectrometer operating at X-band microwave frequency. The results of ESR spectra show that the diamond has a P1 center. This center gives rise to three strong resonance absorption peaks at θ = 90°, φ = 0° due to hyperfine interaction between electron spin and nuclear spin of 14 N . The ESR spectra of 15 N impurity consist of two satellites at the same rotation angle (φ). The effects of isolated substitution nitrogen on carbon atom produced a symmetric distortion from Td to C3V symmetry. According to this symmetry, the resonance magnetic field positions of ESR spectra for the rotation angles of 0°, 90° and 180° are almost overlap. The g-factor values and spin Hamiltonian parameters of 14 N and 15 N are: g = 2.0019, A⊥ = 29.73, A‖ = 40.24 and g = 2.0019, A⊥ = −39.90, A‖ = −57.05, respectively.

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Electron Spin Resonance Of Vo2+ In Likso4 Single Crystals

Zeitschrift für Naturforschung A ◽

10.1515/zna-2004-7-813 ◽

2004 ◽

Vol 59 (7-8) ◽

pp. 488-490

Author(s):

Manu Jain

Keyword(s):

Electron Spin Resonance ◽

Single Crystals ◽

Electron Spin ◽

Esr Spectra ◽

Spin Hamiltonian ◽

X Band ◽

Spin Resonance ◽

Hamiltonian Parameters

Electron spin resonance of VO2+ doped in LiKSO4 single crystals has been studied at 295 K, using an X-band spectrometer. Three sites have been observed. VO2+ enters the lattice at Li and K substitutional sites. The ESR spectra have been analysed and spin-Hamiltonian parameters evaluated. PACS: 76.30 F

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EPR Spectroscopy Elucidates the Electronic Structure of [FeV(O)(TAML)] Complexes

Inorganic Chemistry Frontiers ◽

10.1039/d1qi00522g ◽

2021 ◽

Author(s):

Yujeong Kim ◽

Jin Kim ◽

Linh. K. Nguyen ◽

Yong-Min Lee ◽

Wonwoo Nam ◽

...

Keyword(s):

Electronic Structure ◽

Epr Spectroscopy ◽

Macrocyclic Ligands ◽

Spin Hamiltonian ◽

Pulse Epr ◽

Hamiltonian Parameters

Multifrequency, multitechnique pulse EPR spectroscopy was employed to unravel the spin Hamiltonian parameters of 17O in the [FeV=O] moiety with two different tetraamido macrocyclic ligands (TAMLs), [FeV(O)(TAML-1)]– (1, H4(TAML-1) =...

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