Mixed oxidation state compounds of antimony: a 121Sb Mössbauer study of some antimony–fluorine systems

1978 ◽  
Vol 56 (18) ◽  
pp. 2417-2421 ◽  
Author(s):  
Jack G. Ballard ◽  
Thomas Birchall ◽  
Ronald J. Gillespie ◽  
Edward Maharajh ◽  
David Tyrer ◽  
...  

Antimony-121 Mössbauer spectra for [Sb2F42+][SbF6−]2 and three compounds containing the [Sb3F14−] ion are reported. The Mössbauer data are discussed in relation to their known structures. Two of the compounds give spectra which, on analysis, give η values of unity.

Mineralogia ◽  
2013 ◽  
Vol 44 (1-2) ◽  
pp. 3-12 ◽  
Author(s):  
Kamaleldin M. Hassan ◽  
Julius Dekan

AbstractOlivine basalts from southern Egypt were studied by 57Fe Mössbauer spectroscopy at 297 and 77 K, and by optical microscopy and X-ray diffraction. The 57Fe Mössbauer spectra show three-magnetic sextets, three doublets of ferrous (Fe2+), and a weak ferric (Fe3+) doublet that is attributable to a nanophase oxide (npOx). The magnetic sextets relate to titanomagnetite and the Fe2+ doublets to olivine, pyroxene, and ulvöspinel. Variations in the hyperfine parameters of the various Fe components are attributed to changes in the local crystal chemistry. The intensity of oxidation (Fe3+/ΣFe) in the rocks varies from 20-27% with the oxidized iron largely residing in the titanomagnetite.


Clay Minerals ◽  
1981 ◽  
Vol 16 (3) ◽  
pp. 221-230 ◽  
Author(s):  
A. Kotlicki ◽  
J. Szczyrba ◽  
A. Wiewióra

AbstractFour bands occur in the Mössbauer spectra of pelletal glauconites ranging in age from Cambrian to Oligocene. Components due to Fe3+ in the cis M(2) positions are visible in all the spectra but their shapes depend on the expanding layer content. In the spectrum of the Oligocene glauconite a very well-developed shoulder due to Fe2+ in the trans M(1) positions is observed. In the younger glauconites (15–20% expanding layers) the conventional assignments of the spectra indicate that Fe2+ occupies the trans M(1) positions, the cis M(2) positions being vacant. Conversely, in the Palaeozoic samples (~5% expanding layers) the cis occupancy significantly prevails over trans occupancy.


1982 ◽  
Vol 60 (11) ◽  
pp. 1564-1572
Author(s):  
J. M. Daniels ◽  
H. Y. Lam ◽  
P. L. Li

57Fe Mössbauer spectra were obtained by scattering in a narrow angle geometry from a face, containing the basal plane, of a single crystal of the hexagonal β phase Fe1.67 Ge. Spectra were also obtained from a source of 57Co diffused into an a–c face of a single crystal of this alloy. In all cases, the spectra were satisfactorily resolved into three six-line patterns, and measurements of the relative intensities of the lines indicate that the antiferromagnetic state has a canted structure with all the spins lying in the basal plane.


Nukleonika ◽  
2015 ◽  
Vol 60 (1) ◽  
pp. 7-10 ◽  
Author(s):  
Mieczysław Budzyński ◽  
Virgil C. Constantin ◽  
Ana-Maria J. Popescu ◽  
Zbigniew Surowiec ◽  
Tamara M. Tkachenka ◽  
...  

Abstract The Nd2Fe14B cylindrical magnets were treated with water solutions of alkali, acid, and salt. Mössbauer spectroscopy was applied to study the composition and properties of the surface material of the treated magnets. It is shown that the main phase of the permanent Nd2Fe14B magnet partly decomposes. The released α-Nd at the grain boundaries interacts with water and forms neodymium hydroxide matrix, and the released Fe diffuses into it. The presence of Fe-Nd(OH)3 is reflected in the paramagnet doublet in the Mössbauer spectra of treated neodymium magnets.


1975 ◽  
Vol 53 (22) ◽  
pp. 3371-3373 ◽  
Author(s):  
Jack G. Ballard ◽  
Thomas Birchall

Mössbauer data for α- and β-SnWO4 and Sn(SO3X)2 are reported and the spectrum of SnCl2 re-examined.


1976 ◽  
Vol 54 (5) ◽  
pp. 711-717 ◽  
Author(s):  
R. G. Goel ◽  
H. S. Prasad ◽  
G. M. Bancroft ◽  
T. K. Sham

Dimethyltin chromate and basic dimethyltin and diphenyltin carbonates have been isolated for the first time. Structural features of these compounds, as well as of the previously known basic dimethyltin chromate, have been investigated by examining their infrared, Raman, and Mössbauer spectra. Infrared, Raman, and Mössbauer spectra of [Me2Sn(NCS)]2O have also been examined, and by comparing its spectroscopic data with those for (Me2Sn)2OCrO4, (Me2Sn)2OCO3, and (Ph2Sn)2O(CO3), possible structures have been suggested for the latter compounds. From the combined infrared and Mössbauer data, a structure is also proposed for Me2SnCrO4. All compounds are indicated to have polymeric structures with bridging CrO42− or CO32−.


1981 ◽  
Vol 59 (6) ◽  
pp. 913-917 ◽  
Author(s):  
Nigel S. Dance ◽  
Pablo Dobud ◽  
Colin H. W. Jones

The 125Te Mössbauer spectra of a number of hexahalotellurates have been measured and no significant effects of the size or symmetry of the cation on the Mössbauer parameters were observed. The mixed hexahalotellurates, M2TeX4Y2 (X, Y = Cl, Br, or I), do not exhibit a quadrupole splitting, Δ, and the trends in δ with variation in X and Y are discussed. The pentahalotellurates MTeCl5, MTeBr5, and MTeBr4Cl also yield single line spectra and this is interpreted as evidence of intermolecular bridging. The tetrahaloaryltellurates MArTeX4 and MArTeX3Y (X, Y = Cl, Br, or I) have been studied and the trends in Δ with variation X and Y are consistent with an additive model. The trends in δ are more complex.


Author(s):  
Ahmed D. Al-Rawas ◽  
Abbasher M. Gismelseed ◽  
Subhi Nasir ◽  
Ali A. Yousif ◽  
Mohamed E. Elzain ◽  
...  

A number of meteorites from the desert of Oman, classified as H-chondrites, with known and unknown ages, were studied by using 57Fe Mössbauer spectroscopy to determine their Fe3+-bearing compositions. Mössbauer spectra measured at 78 K were composed of paramagnetic doublets superimposed on magnetic sextets. The doublets are assigned to the silicate minerals olivine and pyroxene and Fe3+ phases. The magnetic sextets in most samples showed the presence of at least three magnetic phases, namely troilite, magnetite and kamacite, which commonly exist in most ordinary chondrites. The relative amounts (area %) of Fe3+ in the known-age meteorites, determined from the Mössbauer spectra, were plotted against their terrestrial ages. The plot was used to estimate the terrestrial ages of meteorites with unknown terrestrial age.


1986 ◽  
Vol 64 (5) ◽  
pp. 987-990 ◽  
Author(s):  
C. H. W. Jones ◽  
R. D. Sharma ◽  
D. Naumann

The 125Te Mössbauer spectra for (CF3)2Te and (C6F5)2Te have been recorded and exhibit significantly larger quadrupole splittings (14.02 and 13.40 mm s−1 respectively) than those of Me2Te (10.5 mm s−1) and Ph2Te (11.0 mm s−1). The dihalides (CF3)2TeX2 and (C66F5)2TeX2 (X = F, Cl,Br) have consistently smaller quadrupole splittings than the dihalides Me2Tex2 and Ph2TeX2. These observations are consistent with the greater electronegativity of the CF3 and C6F5 ligands. The 125Te nmr chemical shifts of (C6F5)Te and its dihalides show a consistent trend to more positive values (increased deshielding) as the electronegativity of the ligands attached to tellurium increases ((C6F5)Te, 297.6 ppm; (C6F5)2TeF2, 1060 ppm). However, for (CF3)2Te and its dihalides a more complex pattern is observed which may be explained by changes in the mean electronic excitation term in the Ramsey paramagnetic shielding term.


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