Search results for "Mossbauer spectra"

Application of 61Ni Mössbauer spectroscopy to chemical problems

1996

Using the possibility to produce 61Co sources at the MAinz MIcrotron, 61Ni Mossbauer spectroscopy was applied to different kinds of chemical problems. Measurements of isomer shifts and V zz values in some common compounds and compounds with unusual chemical bonding for comparison with band structure calculations, measurement of 61Ni Mossbauer parameters in model compounds for hydrogenase and dehydrogenase with an active [NiS4] centre, and study of novel binary NiF3 compounds at helium temperature are presented.

Complexes of diorganotin(IV) dihalides with diphosphoryl compounds and their Mössbauer spectra

1993

Synthese und Strukturen neuer Eisen-Sauerstoff-Alkoxid-Cluster

2004

Der Eisen-Sauerstoff-Alkoxy-Cluster [Fe9O3(OC2H5)21]·C2H5OH kann unter unterschiedlichen Bedingungen zu Molekulen umgesetzt werden, denen alle die allgemeine Formel [Fe5O(OR)8(OR′)5] gemeinsam ist. Erwarmt man [Fe9O3(OC2H5)21]·C2H5OH in Toluol, so entsteht [Fe5O(OC2H5)13], das durch Kristallisation abgetrennt werden kann, wohingegen ein Auflosen von [Fe9O3(OC2H5)21]·C2H5OH in tert-Butylamin zum 1 : 2-Addukt [Fe5O(OC2H5)13]·2 t-Bu-NH2 fuhrt. Mit Triethyl- oder Triphenylsilanol entsteht aus [Fe9O3(OC2H5)21]·C2H5OH wieder ein Sauerstoff-Eisencluster des gleichen Motivs: [Fe5O(OC2H5)8{OSi(C2H5)3}5] bzw. [Fe5O(OC2H5)8{OSi(C6H5)3}5]. Die Molekulstruktur [Fe5O(OC2H5)8{OSi(C2H5)3}5], die uber Rontg…

A heptanuclear Fe(II)–Fe(III)6 system with twelve unpaired electrons

2000

Abstract The pentadentate ligand 5 LH2 = saldptn = N,N′-bis(1-hydroxy-2-benzyliden)-1,7-diamino-4-azaheptane has been prepared by a Schiff base condensation between 1,7-diamino-4-azaheptane and the corresponding salicyaldehyde. Its complexation with Fe(III) gave the high-spin (S=5/2) complex of [Fe III ( 5 L)Cl]. This precursor was combined with [Fe(CN)6]4− and a blue heptanuclear complex [FeII{(CN)Fe III ( 5 L)}6]Cl2 resulted. This system belongs to the class of high-spin molecules possessing twelve unpaired electrons (S=6) as proven by the magnetic susceptibility measurements and Mossbauer spectra.

Physico-chemical characterization of perlite of various origins

1985

Abstract Pearlstones (perlite) from Sardinia (Italy). Milos (Greece) and Siberia (USSR) have been evaluated in terms of chemical composition, phase analysis, iron distribution, morphology and thermal properties, for application as raw material in zeolite synthesis.

57Fe Mössbauer spectroscopy predicts superstructure for K0.08[Cu(II)(N,N'app)Cl]2[Fe(III)(CN)6].0.92H3O.3H2O.

2007

The compound [Cu(N,N'app)Cl](2)[Fe(CN)(6)].xH(2)O, with N,N'app being bis(N,N'-3-aminopropylpiperazine), was prepared and its structure determined by single crystal X-ray analysis, confirming a ratio of two copper complexes to one iron complex; (57)Fe Mössbauer spectra showed three quadrupole doublets typical of iron(iii) low spin species which call for the presence of a superstructure.

57Fe and119Sn Mössbauer investigations on some substituted barium hexaferrites

1994

57Fe and119Sn Mossbauer measurements have been carried out on powder samples of three differently substituted M-type barium hexaferrites. By57Fe Mossbauer measurements in an external magnetic field applied parallel to the γ-ray direction, we found a canted spin structure for all samples. Furthermore, we detected a strong preference of the Sn4+ ions for the 4f2 sites. From57Fe Mossbauer measurements aboveT N, we conclude that the substitution does not influence the 2b sites. The analysis of the magnetically split119Sn Mossbauer spectra at room temperature in the case of the Co-Sn and Zn-Sn substituted samples shows a strong difference between the two. The spectra were interpreted due to the …

Study of very thin oxide layers by conversion and Auger electrons

1990

Oxidic layers as thin as 20–30 A on α-Fe and stainless steel are studied by57Fe-DCEMS with K-conversion electrons and ICEMS. No indication of a vanishingf-factor could be found. Mossbauer spectra, recorded by use of LMM-Auger electrons (AEMS) and by electrons emitted with energies below 15 eV (LEEMS), contain information on the surface layer as well as on the bulk material, showing that part of these electrons are due to secondary effects and the high escape depths of K-conversion electrons.

Basic Physical Concepts

2010

Mossbauer spectroscopy is based on recoilless emission and resonant absorption of γ-radiation by atomic nuclei. The aim of this chapter is to familiarize the reader with the concepts of nuclear γ-resonance and the Mossbauer effect, before we describe the experiments and relevant electric and magnetic hyperfine interactions in Chaps. 3 and 4. We prefer doing this by collecting formulae without deriving them; comprehensive and instructive descriptions have already been given at length in a number of introductory books ([7–39] in Chap. 1). Readers who are primarily interested in understanding their Mossbauer spectra without too much physical ballast may skip this chapter at first reading and p…

1H NMR spectra of Ph2SbX, PhSbX2, and Ph3SbX2 (XCl, Br, I); 121Sb Mössbauer spectra of PhSbX2 and crystal structure of Ph2SbI1

1996

1H NMR spectroscopic data of Ph2SbX, PhSbX2, and Ph3SbX2 (XCl, Br, I) have been determined by iterative simulation. 121Sb Mossbauer spectra of PhSbX2 (XCl, Br, I) have been measured. The synthesis of Ph2SbI is achieved by reaction of Ph2SbCl with NaI in ethanol. The crystal structure of Ph2SbI consists of molecules with pyramidal C2SbI units.