A. Forster

Precision measurement of the electric quadrupole interaction in zinc metal

To decide on the validity of various values for the quadrupole coupling constant of Zn metal available in the literature, we have used the frequency modulation technique to the 93.3 keV Mössbauer resonance of67Zn. We obtained for a67Zn metal absorber: e2qQ/h =vO = 12.34 ± 0.03 MHz. The asymmetry parameter was found to be η=0.00−0+0.06. These precise values can be used as a calibration standard for67Zn Doppler drives.

Mössbauer study of illite associated with iron oxi-hydroxides

An illite separated from mylonites from the southern rim of the Bohemian massif was studied by Mössbauer spectroscopy at temperatures between 300 and 1.8 K. The iron is mainly contained in oxides associated with the illite. Only 13% of the iron are structural Fe3+ and Fe2+ within the clay mineral matrix. The transformations of the oxidic iron during heating at temperatures up to 1250°C were followed by Mössbauer measurements at 300 and 4.2 K.

Mössbauer spectroscopy with the 93 keV-resonance in67Zn

The procedures and results of high resolution Mössbauer experiments performed with the 93.3 keV resonance in absorbers of67ZnO,67ZnS (both wurtzite and sphalerite structures),67ZnSe,67ZnTe and67ZnF2 are reported. An essentially linear dependence between the isomer shift and the Pauling electronegativity of the ligands was found. A value ofΔ 〈r2〉=+11×10−3 fm2 is estimated. The Mössbauer parameters for both ZnS structures are equal within present limits of error. In particular, no quadrupole interaction was observed in the wurtzite modification. This indicates a nearly identical local symmetry at the Zn site in the two ZnS structures.

The quadrupole interaction in zinc metal

Abstract Using the 93.3 keV Mossbauer transition in 67Zn the electric field gradient in zinc metal has been determined and was found to be axially symmetric with a value of eq = + (3.02 ± 0.05) × 1 017V/cm2.

A microprocessor controlled spectrometer for frequency modulation Mössbauer measurements

A Mossbauer spectrometer for the frequency modulation technique using piezo-quartzes is described. All its subsystems like the wave form synthesizer, the voltage divider and the data storage system are centrally controlled by a microprocessor. The system has been used for precision determination of hyperfine splittings of the very high resolution 93.3 KeV Mossbauer resonance in 67Zn.

Mössbauer study of the Cu-Zn alloy system

Using the 93.3keV transition in67Zn, the Lamb-Mössbauer factor, the electron density and the electric field gradient at the Zn nucleus have been determined for pure Zn metal, the ε−, γ−, Β′−, and α-phases as well as pure Cu metal.

High pressure Mössbauer investigation of 67ZnS

Abstract The 67 Zn (93 keV) Mossbauer spectrum of ZnS has been investigated in the pressure range up to 33 kbar at 4.2 K. A linear increase with pressure of the s-electron density at the Zn nucleus is seen.