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The M\"ossbauer effect of ${\mathrm{Fe}}^{57}$ in the metalloprotein ferrichrome $A$ (FA) has been investigated at temperatures between 0.98 and 300\ifmmode^\circ\else\textdegree\fi{}K; some cases absorber was placed an external field 18 kOe, oriented perpendicular to propagation direction. polycrystalline paramagnetic sample exhibited temperature-, field-, concentration-dependent magnetic hyperfine structure. At 0.98\ifmmode^\circ\else\textdegree\fi{}K zero field, a well-resolved six-line...

A theoretical and experimental study was made of the shift in atomic core-electron binding energies caused by chemical environment. Two models are presented to account for these “chemical shifts.” The first uses an energy cycle break into a free-ion contribution classical Madelung contribution. contributes significant part binding-energy shift. It can, principle, be evaluated rigorously although there is some ambiguity as surface correction. reference level must also considered comparing...

The Mn K-edge x-ray absorption spectra for the pure S states of tetranuclear cluster oxygen-evolving complex photosystem II during flash-induced S-state cycling have been determined. relative populations in samples given 0, 1, 2, 3, 4, or 5 flashes were determined from fitting electron paramagnetic resonance (EPR) multiline signal oscillation pattern to Kok model. edge 3 combined with EPR information calculate spectra. positions (defined as zero-crossing second derivatives) are 6550.1,...

Sharp-line fluorescence, paramagnetic resonance in the ground state, and optical absorption due to ${\mathrm{Mn}}^{4+}$ $\ensuremath{\alpha}$-${\mathrm{Al}}_{2}$${\mathrm{O}}_{3}$ have been observed (analog of ${\mathrm{Cr}}^{3+}$). The valence state is obtained by charge compensation with ${\mathrm{Mg}}^{2+}$. increased compared ${\mathrm{Cr}}^{3+}$ results a stronger crystal field greater covalency whose effects are clearly seen both results. splitting 0.39...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTState of manganese in the photosynthetic apparatus. 1. Extended x-ray absorption fine structure studies on chloroplasts and di-.mu.-oxo-bridged dimanganese model compoundsJ. A. Kirby, S. Robertson, J. P. Smith, C. Thompson, R. Cooper, M. KleinCite this: Am. Chem. Soc. 1981, 103, 18, 5529–5537Publication Date (Print):September 1, 1981Publication History Published online1 May 2002Published inissue 1 September...

A technique for making 31P NMR spectroscopic measurements in rat kidney, heart, and liver vivo is presented. Two-turn solenoid coils were surgically implanted around the organ sufficiently advance of experiments to allow recovery animal. These chronically allowed acquisition high-resolution spectra at 40.5 97.3 MHz. No resolution improvement occurred higher field. Spectra stable up 24 hr, during which time a variety could be performed. By accumulating 10-min intervals, effects...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTState of manganese in the photosynthetic apparatus. 2. X-ray absorption edge studies on membraneJ. A. Kirby, D. B. Goodin, T. Wydrzynski, S. Robertson, and M. P. KleinCite this: J. Am. Chem. Soc. 1981, 103, 18, 5537–5542Publication Date (Print):September 1, 1981Publication History Published online1 May 2002Published inissue 1 September 1981https://pubs.acs.org/doi/10.1021/ja00408a043https://doi.org/10.1021/ja00408a043research-articleACS...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHead group modulation of membrane fluidity in sonicated phospholipid dispersionsD. M. Michaelson, A. F. Horwitz, and P. KleinCite this: Biochemistry 1974, 13, 12, 2605–2612Publication Date (Print):June 1, 1974Publication History Published online1 May 2002Published inissue 1 June 1974https://pubs.acs.org/doi/10.1021/bi00709a021https://doi.org/10.1021/bi00709a021research-articleACS PublicationsRequest reuse permissionsArticle...

We have measured the magnetic circular dichroism of ferrocytochrome c from 350 to 1000 nm and MCD ferricytochrome 750 nm. present expressions for shapes absorption spectra in presence a field randomly oriented molecules general case which band is split zero field, two components different intensities. After correcting effects unresolved zero-field splitting, we find that ``angular momentum'' Q00 Fe(II) cyt 7.9 μB. show 23-fold decrease upon oxidation Fe(III) due about fivefold increased...

The limits of electron spin resonance detection sensitivity are investigated for absorption and induction spectrometers employing superheterodyne detection. the conventional bridge spectrometer is found to decrease rapidly below theoretical limit set by noise figure receiver when klystron power increased above about 10 mw. This shown arise from extreme frequency dependence balance. bimodal cavity spectrometer, which has a highly stable independent balance, shows no departure limit. Flicker...

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Abstract A new concept of the NMR Mobile Universal Surface Explorer (NMR‐MOUSE) using simple bar magnets instead u‐shaped is described. The magnetic field profiles are comparatively homogeneous in extended lateral planes, and close to magnet pole face axial gradient nearly constant. Different geometric arrangements figure‐8 coils adapted sample geometry Simulations measurements from radio frequency discussed. © 2002 Wiley Periodicals, Inc. Concepts Magnetic Resonance (Magn Reson Engineering)...

For bulk samples of superconducting Y${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ powder and pellets subject to a dc magnetic field ${H}_{0}$ parallel ac ${H}_{1}$ at frequency $f\ensuremath{\sim}{10}^{3} \mathrm{to} {10}^{5}$ Hz, we report data on the generated harmonic power $P(\mathrm{nf})$ up $n\ensuremath{\approx}40$, finding: (1) If ${H}_{0}=0$, only odd harmonics; (2) if ${H}_{0}\ensuremath{\ne}0$, even harmonics are additionally generated; (3) for sufficiently large...

Abstract The electron-capture decay of a cobalt-57 atom triggers an Auger event resulting in the loss several electrons from molecule which it is incorporated. 14.4 keV Mössbauer emission conveys information regarding chemical forms daughter iron-57 ‘stabilized’ within 10−7 sec following electron capture. During this time electronic relaxation occurs completely and tens volt energy deposited as result neutralization. We find that ethylenediamine tetra-acetate, bis-salicylaldehyde...

Recent experimental studies have reported anomalous and contradictory results for the absorption of left right circularly polarized light (LCPL RCPL) by zinc magnesium coproporphyrins in presence a magnetic field: both compounds, bands distinctly different shapes at room temperature; 77°K unexplained shoulders appear spectra polarizations but not compound; value angular momentum lowest energy excited state computed from separation peaks LCPL RCPL differs obtained circular dichroism (MCD)...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEXAFS structural study of FX, the low-potential iron-sulfur center in photosystem IAnn E. McDermott, Vittal K. Yachandra, Ronald D. Guiles, Kenneth Sauer, Melvin P. Klein, Kevin G. Parrett, and John H. GolbeckCite this: Biochemistry 1989, 28, 20, 8056–8059Publication Date (Print):October 1, 1989Publication History Published online1 May 2002Published inissue 1 October 1989https://doi.org/10.1021/bi00446a013RIGHTS & PERMISSIONSArticle...

An instrument employing several novel features has been assembled for the measurement of magnetic and natural circular dichroism (MCD CD) in visible, ultraviolet near infrared spectral regions. The is fitted with two magnets: an electromagnet routine use a superconducting magnet when higher performance required. contributions CD MCD are separated by measuring net spectrum twice; first field parallel to Poynting vector optical beam then it antiparallel. value activity each wavelength...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation L. N. Kramer, M. P. Klein; Chemical Shifts in Core Electron Binding Energies of Iron Sulfur Complexes Determined by Photoelectron Spectroscopy. J. Chem. Phys. 15 October 1969; 51 (8): 3618–3620. https://doi.org/10.1063/1.1672562 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley...

High-resolution measurements of photoelectrons produced by x-rays in compounds iodine and europium have revealed chemical shifts the core-level energies, from which bonding information can be obtained. The observed shifts, 0.8 electron volt per unit change oxidation number 9.6 volts europium, are discussed terms two theoretical models.

Abstract Herein, the design of novel and safe electrolyte formulations for high‐voltage Ni‐rich cathodes is reported. The solvent mixture comprising 1,1,2,2‐tetraethoxyethane propylene carbonate not only displays good transport properties, but also greatly enhances overall safety cell thanks to its low flammability. influence conducting salts, that is, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) bis(fluorosulfonyl)imide (LiFSI), additives bis(oxalato)borate (LiBOB)...