Element specific magnetization has been determined at the surface and in the bulk of Co2Cr0.6Fe0.4Al Heusler alloy films grown on α-Al2O3 and capped by Al, using x-ray magnetic circular dichroism both in transmission and total electron yield. The magnetic moments for Co and Fe are considerably reduced at the upper surface in comparison to their values in the bulk of the film. The large reduction at room temperature of 17% for thick films averaged along the electron escape depth implies an even larger reduction at the topmost layer which is crucial for spin-dependent transport. The surface magnetization decreases additionally with respect to the bulk value with decreasing film thickness below 20nm.

Quaternary Heusler alloys Co 2 Cr 1-x FexAl with varying Cr to Fe ratio x were investigated experimentally and theoretically.The electronic structure and spectroscopic properties were calculated using the full relativistic Korringa-Kohn-Rostocker method with coherent potential approximation to account for the random distribution of Cr and Fe atoms as well as random disorder.Magnetic effects are included by the use of spin dependent potentials in the local spin density approximation.Magnetic circular dichroism in X-ray absorption was measured at the L 2,3 edges of Co, Fe, and Cr of the pure compounds and the x = 0.4 alloy in order to determine element specific magnetic moments.Calculations and measurements show an increase of the magnetic moments with increasing iron content.Resonant (560eV -800eV) soft X-ray as well as high resolution -high energy (≥ 3.5keV) hard X-ray photo emission was used to probe the density of the occupied states in Co 2 Cr 0.6 Fe 0.4 Al.

The family of half-Heusler compounds offers a variety of half-metallic ferromagnetic materials. We have applied the Mössbauer spectroscopy to study the atomic order, local surroundings and hyperfine fields to several half-Heusler compounds. 121Sb Mössbauer study of the compound CoMnSb revealed the presence of two nonequivalent antimony positions in the elementary cell and enabled to identify the structure. 119mSn, 155Gd and 197Au Mössbauer spectroscopic studies were used to characterize the properties of ferromagnetic granular material based on the half-Heusler ferromagnet MnAuSn in the antiferromagnetic GdAuSn matrix.

Zeitschrift für anorganische und allgemeine ChemieVolume 630, Issue 11 p. 1771-1771 Poster Charakterisierung von dotierten Heusler-Verbindungen: Co2Cr1−xFexAl S. Wurmehl, Corresponding Author S. Wurmehl Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzInstitut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorG. H. Fecher, G. H. Fecher Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorH. C. Kandpal, H. C. Kandpal Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorK. Kroth, K. Kroth Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorH.-J. Elmers, H.-J. Elmers Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorG. Schönhense, G. Schönhense Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorC. Felser, C. Felser Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorJ. Morais, J. Morais Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, BrasilSearch for more papers by this authorY. Hwu, Y. Hwu Academia Sinica, Taipei, 11529, TaiwanSearch for more papers by this authorR. Klauser, R. Klauser National Synchrotron Radiation Research Center, Hsinchu, 30077, TaiwanSearch for more papers by this author S. Wurmehl, Corresponding Author S. Wurmehl Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzInstitut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorG. H. Fecher, G. H. Fecher Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorH. C. Kandpal, H. C. Kandpal Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorK. Kroth, K. Kroth Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorH.-J. Elmers, H.-J. Elmers Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorG. Schönhense, G. Schönhense Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorC. Felser, C. Felser Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorJ. Morais, J. Morais Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, BrasilSearch for more papers by this authorY. Hwu, Y. Hwu Academia Sinica, Taipei, 11529, TaiwanSearch for more papers by this authorR. Klauser, R. Klauser National Synchrotron Radiation Research Center, Hsinchu, 30077, TaiwanSearch for more papers by this author First published: 31 August 2004 https://doi.org/10.1002/zaac.200470154Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume630, Issue11September 2004Pages 1771-1771 RelatedInformation

Zeitschrift für anorganische und allgemeine ChemieVolume 630, Issue 11 p. 1738-1738 Poster Strukturaufklärung der Halb-Heusler-Verbindung CoMnSb mit Hilfe von 121Sb-Mößbauer-Spektroskopie K. Kroth, Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorV. Ksenofontov, Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorG. Melnyk, Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorC. Felser, Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this author K. Kroth, Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorV. Ksenofontov, Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorG. Melnyk, Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this authorC. Felser, Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Staudingerweg 9, D-55099 MainzSearch for more papers by this author First published: 31 August 2004 https://doi.org/10.1002/zaac.200470091AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume630, Issue11September 2004Pages 1738-1738 RelatedInformation

The magnetic moment of the 161 keV state of 133 Cs was remeasured by the 1PAC technique in an external magnetic field of 9.5 T as μI(161keV) = 2.0(2)n.m. The known half-life of the 161 keV state, T1/2 = 190(15)ps, was confirmed by a Coulomb-excitation experiment. The 161 keV state as well as the few other states for which large B(E2)↑ values are observed exhibit the characteristic properties of a ground state core-excitation multiplet as proposed by de-Shalit. A high precision remeasurement of the 276 keV–161 keV γ-γ angular correlation by use of a three Ge(Li) detector system gave A2 = −0.495(5) and A4 = −0.54(6), and confirms the result obtained by Winn and Sarantites which is in contradiction to all previous data. A comparison of the M1/E2 mixing ratio derived from this angular correlation for the 161 keV transition with recent precise data for the total conversion coefficient proves that anomalous conversion is present and leads to the penetration parameter λ = +25(9).

Sign and magnitude of the magnetic hyperfine field suggest the existence of a localized moment of about −0.4 µ B at the site of Os in Gd.

Time differential perturbed angular correlation spectra of111Cd in ferromagnetic polycrystalline Dy have been measured at 4.2 K in external magnetic fields up to 60 kG. The experimental data were well reproduced by a calculation which assumed that the angular distribution of the magnetic hyperfine fields is identical to that of the magnetic moments of the 4f-shells. The distribution of the 4f-moments was derived from magnetic anisotropy data. The results of this work seem to justify the application of the integral perturbed angular correlation technique for the determination of magnetic hyperfine fields in incompletely polarized ferromagnetic samples. The magnetic hyperfine fields of177Hf:Gd and177Hf:Dy have been measured by this method as:Hhf(Hf:Gd)=−375(60)kG andHhf(Hf:Dy)=−225(45)kG.

Theg-factor of the 4 1 + -state of202Pb was investigated by the IPAC-technique. Inspite of the long half-life, which was measured as:T1/2(4 1 + -state)=1.97(2)ns and the strong applied external magnetic field of 95.0 kG no rotation of the 787 keV-(422keV)-961 keVγ-γ angular correlation could be observed. Theg-factor must therefore be very small. A computer fit gave the limits:g(4 1 + -state)=+0.002(4).

The Larmor-precession frequencies for197Hg in Fe have been determined to beω L = 1291 ±25 MHz at 293 K andω L = 1334±25 MHz at 105 K. For199Hg in Feω L =1372±50 MHz has been measured at 293 K. The half-lives of the 5/2− states in197Hg and199Hg have been remeasured asT1/2(197Hg)=8.1±0.16 nsec andT1/2(199Hg)=2.45±0.05 ns, respectively. The magnetic moment of the 5/2− 158keV state in199Hg was redetermined by the integral perturbed angular correlation method in an external magnetic field of 47kG asμ(5/2 − ) = 0.905±0.091 nm. With this new value consistency for the magnetic hyperfine fields at Hg in Fe measured with the TDPAC-method and with the NMR/ON-method is obtained. This fact is used to determine theg-factors of the 5/2− states in197Hg and199Hg more precisely fromω L -values given above:g(197Hg)=0.342(6);g(199Hg)=0.352(13). The magnetic moments of the first excited 2+ states in198–204Hg isotopes which rely on calibrations with the199Hg-g-factor, are revised.

The half-life of the 202.5 keV level in 90Y has been remeasured by the γγ delayed coincidence technique to 250(7) ps. The g-factor of this state has been measured by the integral perturbed angular correlation technique using the large field of a superconducting magnet as g = −0.283(23). The intensity ratio of the 682 keV E5 transition to the 480 keV M4 transition depopulating the 7+ state in 90Y has been determined to be 4.0(8) × 10−3. The electromagnetic properties of the low lying states in 90Y are discussed within the framework of the jj coupling shell model.