scholarly journals H/D isotope effect and magnetic properties of cyanide-bridged Nd(III)-Fe(III) complex

2011 ◽  
Vol 1 (1) ◽  
pp. 425-428
Author(s):  
T. Akitsu ◽  
Y. Kimoto ◽  
Y. Yamada ◽  
K. Nomura
Keyword(s):  
Magnetic Properties ◽  
Hydrogen Bonds ◽  
Crystal Lattice ◽  
Temperature Dependence ◽  
Isotope Effect ◽  
Mössbauer Spectra ◽  
Isotope Effects ◽  
Intermolecular Hydrogen Bonds ◽  
Coordination Environment ◽  
Mossbauer Spectra

AbstractWe have prepared four H/D isotope forms of Nd(DMF)4(H2O)3Fe(CN)6·H2O (DMF = N,N-dimethylformamide) by using D2O or DMF-d1. Temperature dependence of magnetization exhibits H/D isotope effects resulting from intermolecular hydrogen bonds. Temperature dependence of Fe 2p3/2 and 2p1/2 XAS and 57Fe Mössbauer spectra suggested that the influence of coordination environment could be distiguished from the influence of crystal lattice based on preliminary crystallographic results.

scholarly journals Structure and thermal properties associated with some hydrogen bonds in crystals. IV. Isotope effects in some acid phosphates

1942 ◽  
Vol 179 (979) ◽  
pp. 399-407 ◽  
Keyword(s):  
Thermal Properties ◽  
Hydrogen Bonds ◽  
Crystal Lattice ◽  
Isotope Effect ◽  
Isotope Effects ◽  
Monoclinic Structure ◽  
Monoclinic Form

The isotope effect has been measured for (NH 4 )H 2 PO 4 . Expansion of the crystal lattice takes place on substituting deuterium for hydrogen. The expansion is in the direction of the hydrogen bonds, and is of the same magnitude as in the isomorphous KH 2 PO 4 . A contraction of the lattice at right angles to the plane containing the hydrogen bonds is considerably larger for (NH 4 )H 2 PO 4 than for KH 2 PO 4 . From an application of the calculus of errors, the accuracy of the results is estimated to be α 11 = + 0.00269 ± 0.00006, α 33 = - 0.00123 ± 0.00009. Further investigations on the monoclinic form of KD 2 PO 4 has shown the presence of curious diffuse reflexions in moving-film photographs. Attempts to obtain (NH 4 )D 2 PO 4 or KH 2 PO 4 in the monoclinic structure were unsuccessful.

Mössbauer spectra and magnetic properties of Tm0.65Sr0.35Fe x Mn1 − x O3 (x = 0.3, 0.35, 0.4)

2013 ◽  
Vol 49 (9) ◽  
pp. 939-942
Author(s):  
V. V. Parfenov ◽  
A. V. Pyataev ◽  
I. I. Nig’matullina ◽  
Sh. Z. Ibragimov
Keyword(s):  
Magnetic Properties ◽  
Mössbauer Spectra ◽  
Mossbauer Spectra

Dithiolium and diselenolium compounds of the transition metals

1969 ◽  
Vol 22 (1) ◽  
pp. 83 ◽  
Author(s):  
RL Martin ◽  
IM Stewart
Keyword(s):  
Transition Metals ◽  
Temperature Dependence ◽  
Mössbauer Spectra ◽  
Mossbauer Spectra ◽  
First Time

The preparations are reported of an extended series of compounds of the type ML2X4 where M is Mn, Fe, Co, or Ni; X is Cl or Br; and L is analytically identical with dithioacetylacetone. ��� Electronic, infrared, and Mossbauer spectra together with the temperature dependence of the magnetism (80-300�K) of these compounds establish-contrary to previous suggestions in the literature-that they should be properly formulated as tetrahalometallate salts of the 3,5- dimethyl-1,2-dithiolium cation. Simple salts of this cation (such as the iodide) have also been isolated. ��� During the course of this work salts (I- and [CoCl4]2-) of the hitherto unknown 3,5-dimethyl-1,2-diselenolium ion were synthesized and characterized for the first time.

Local Spin Configurations of Fe Atoms in Microinhomogeneous PdMnxFe1-x Alloys

2009 ◽  
Vol 152-153 ◽  
pp. 49-53
Author(s):  
V.V. Serikov ◽  
N.M. Kleinerman ◽  
N.V. Volkova ◽  
N.I. Kourov
Keyword(s):  
Magnetic Properties ◽  
Intermetallic Compound ◽  
Curie Temperature ◽  
Mössbauer Spectra ◽  
Ferromagnetic Phase ◽  
Multiphase Medium ◽  
Mossbauer Spectra ◽  
Local Spin ◽  
Ferromagnetic Alloys ◽  
Intermediate Concentration

The Mössbauer spectra of PdMnxFe1-x alloys obtained at 80 K and at 300 K were studied in the 0.2 < x < 0.8 concentration range, in which there realizes a microinhomogeneous multiphase medium formed by isostructure phases of the constituent compositions: ferromagnetic PdFe (ТС=730 К) alloy undergoing atomic ordering and antiferromagnetic PdMn (TN=815 К) intermetallic compound. Magnetic properties studies evidence the presence of a third presumably noncollinear phase with its own ordering temperature lying below the Curie temperature of the ferromagnetic phase in the 0.2 < x < 0.8 concentration range. The Mössbauer spectra at 300 K exhibit a doublet for antiferromagnetic alloys (x > 0.8) and a sextet at Hhf ~350 kOe for ferromagnetic alloys (x < 0.2). In the intermediate concentration range several peaks 0 < Hhf < 350 kOe have been observed in the P(Hhf) curves, which result from microinhomogeneous multiphase state.

Untersuchungen zur Reaktion der Alkoholdehydrogenase mit Tritium-markierten Substraten

1966 ◽  
Vol 21 (6) ◽  
pp. 540-546 ◽  
Author(s):  
Dieter Palm
Keyword(s):  
Alcohol Dehydrogenase ◽  
Temperature Dependence ◽  
Isotope Effect ◽  
Substrate Binding ◽  
Isotope Effects ◽  
Direct Interaction ◽  
Enzyme Complex ◽  
Temperature Range ◽  
Yeast Alcohol Dehydrogenase ◽  
Rate Controlling Step

Unexpectedly, the isotope effect of ethanol-1-Τ as a substrate of yeast alcohol dehydrogenase, increases with rising temperature from kH/kT = 3.2 at 5 —15°C to 3.8—4.7 at 20 —35 °C. This suggests a change of the rate controlling step as proposed by MÜLLER-HILL and WALLENFELS, who investigated the temperature dependence of the activation energies in this temperature range. A comparison of the affinities of propanol and butanol with the isotope effects of the corresponding tritium labelled compounds (propanol-1-Τ 6.7 at 25 °C, butanol-1-Τ 6.8 at 25 °C) supports the proposal, that during substrate binding, there must be a direct interaction between the enzyme complex and hydrogen which is removed in the reaction. These influences are less pronounced for the ethanol homologues which are bound less tightly to the enzyme. Therefore the H transfering step proper gives a greater contribution to the overall experimental isotope effect.

Preparation and characterization of iron oxide pillared montmorillonite

Clay Minerals ◽  
1988 ◽  
Vol 23 (4) ◽  
pp. 367-377 ◽  
Author(s):  
D. H. Doff ◽  
N. H. J. Gangas ◽  
J. E. M. Allan ◽  
J. M. D. Coey
Keyword(s):  
Magnetic Properties ◽  
Iron Oxide ◽  
Powder Diffraction ◽  
Mössbauer Spectra ◽  
Pillared Clay ◽  
Cross Linking ◽  
X Ray ◽  
Pillared Montmorillonite ◽  
Mossbauer Spectra

AbstractPillared smectites in which the pillars consist of iron oxide are expected to have interesting and unusual magnetic properties. Several possible routes by which such materials might be made have been investigated, namely intercalation of hydroxy-Fe(III) polycations, mixed hydroxy-Fe(III)/Al polycations, phenanthroline-Fe(II) cations, and trinuclear Fe(III) acetato cations into Na-montmorillonite. Only the last of these yielded a pillared clay (PILC) on calcination. The products have been characterized using X-ray powder diffraction and 57Fe Mössbauer spectroscopy. The precursor Fe-PILC has a d-spacing of 21 Å and expands to 23 Å on solvation with glycol. The calcined Fe-PILC has a d-spacing of 19 Å (gallery height 9·4 Å) and does not expand with glycol, confirming cross-linking of the layers. From Mössbauer spectra at 4·2 K it is estimated that there are of the order of some hundred Fe atoms per pillar.

scholarly journals Manganese/Yttrium Codoped Strontium Nanohexaferrites: Evaluation of Magnetic Susceptibility and Mossbauer Spectra

Nanomaterials ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 24 ◽  
Author(s):  
Munirah Almessiere ◽  
Yassine Slimani ◽  
Hakan Güngüneş ◽  
Abdulhadi Baykal ◽  
S.V. Trukhanov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Mössbauer Spectra ◽  
Ac Susceptibility ◽  
Sol Gel ◽  
Hyperfine Magnetic Field ◽  
Analytical Techniques ◽  
Magnetic Interactions ◽  
Mossbauer Spectra

Manganese (Mn)- and yttrium (Y)-substituted Sr-nanohexaferrites (MYSNHFs) of composition Sr1−xMnxFe12−xYxO19 (with 0.0 ≤ x ≤ 0.5) were prepared by citrate sol-gel autocombustion method. As-prepared MYSNHFs were characterized via diverse analytical techniques to determine the influence of Mn and Y cosubstitution on their microstructures and magnetic properties. 57Fe Mössbauer spectra of the MYSNHFs were used to evaluate the variation in the line width, isomer shift, quadrupole splitting, and hyperfine magnetic field values. It was shown that the dopant ions could preferentially occupy the 12k, 4f2, and 2b sites. Furthermore, the observed shift in the blocking temperatures of the studied MYSNHFs towards lower values with rising Mn2+ and Y3+ contents was attributed to the overall particles size reduction. Meanwhile, the AC susceptibility of the proposed MYSNHFs revealed that the magnetic interactions were weakened with the increase in dopant contents which was ascribed to the replacement of both Sr2+ and Fe3+ ions by the Mn2+ and Y3+ dopants.

Mössbauer spectra and magnetic properties of iron nitrides

1994 ◽  
Vol 94 (1) ◽  
pp. 2067-2073 ◽  
Author(s):  
Qinian Qi ◽  
K. O'Donnell ◽  
E. Touchais ◽  
J. M. D. Coey
Keyword(s):  
Magnetic Properties ◽  
Mössbauer Spectra ◽  
Iron Nitrides ◽  
Mossbauer Spectra

scholarly journals Crystal structure of [bis(2,6-diisopropylphenyl) phosphato-κO]tris(methanol-κO)lithium methanol monosolvate

2015 ◽  
Vol 71 (5) ◽  
pp. 443-446 ◽  
Author(s):  
Mikhail E. Minyaev ◽  
Ilya E. Nifant'ev ◽  
Alexander N. Tavtorkin ◽  
Sof'ya A. Korchagina ◽  
Shadana Sh. Zeynalova
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Tetrahedral Coordination ◽  
Intermolecular Hydrogen Bonds ◽  
Coordination Environment ◽  
The Family ◽  
Phosphate Diesters ◽  
Distorted Tetrahedral Coordination

Crystals of the title compound, [Li{OOP(O-2,6-iPr2C6H3)2}(CH3OH)3]·CH3OH or [Li(C24H34O4P)(CH3OH)3]·CH3OH, have been formed in the reaction between HOOP(O-2,6-iPr2C6H3)2and LiOH in methanol. The title compound is of interest as it represents the first reported crystal structure of the family of lithium phosphate diesters. The {Li(CH3OH)3[O2P(O-iPr2C6H3)2]} unit displays the Li atom in a slightly distorted tetrahedral coordination environment and exhibits one intramolecular O—H...O hydrogen bond between a coordinating methanol molecule and the terminal non-coordinating O atom of the phosphate group. The unit is connected with two non-coordinating methanol molecules through two intermolecular O—H...O hydrogen bonds, and with a neighbouring unit through two other O—H...O interactions. These intermolecular hydrogen bonds lead to the formation of infinite chains along [100]. There are no significant interactions between the chains.

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