FN ISI Export Format VR 1.0 PT J AU Vertes, A Klencsar, Z Vanko, G Marek, T Suvegh, K Homonnay, Z Kuzmann, E TI Nuclear techniques in the elucidation of chemical structure SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY NR 77 AB The paper offers three applications of nuclear methods in the research of chemical structure. First, progress in positron annihilation spectroscopy is illustrated by a positron beamline study, which obtained results that are not available through conventional experiments. The positron beam was used for the study of Langmuir-Blodgett (LB) films containing 4-58 layers of arachidic acid and its salts. These measurements have shown that this emerging technique is capable of characterizing even such elusive systems. Second, the potential of Mossbauer spectroscopy to answer current challenges of solid state chemistry are shown in a study on perovskites of recent interest. Eu-151 Mossbauer spectroscopy was used to study the effect of Pr substitution in EuBa2Cu3O7-delta. It was shown that the introduction of Pr into the rare earth site as well as into the Ba site results in the appearance of extra electrons both in the copper oxide planes and at the 4f shell of Eu cations. The observed effects were explained by the hole filling effect of Pr. Finally, a survey is presented on the recently developed techniques for nuclear resonant scattering of synchrotron radiation, an exciting and very rapidly developing extension to conventional Mossbauer spectroscopy. An interesting new result is that nuclear inelastic scattering experiments performed on solutions of Fe-57 complexes show contribution from vibrations rather than from diffusion to the inelastic spectra. CR BARON AQR, 1997, PHYS REV LETT, V79, P2823 BEDNORZ JG, 1986, Z PHYS B CON MAT, V64, P189 BLACKSTEAD HA, 1996, PHYS REV B, V54, P6122 BLACKSTEAD HA, 1995, PHYS REV B, V51, P11830 BOTTYAN L, 1998, HYPERFINE INTERACT, V113, P295 BOTTYAN L, IN PRESS BRANDL D, 1995, THIN SOLID FILMS, V256, P220 BRANDT W, 1960, PHYS REV, V120, P1289 CHU CW, 1988, PHYS REV LETT, V60, P941 CHUMAKOV A, 1998, HYPERFINE INTERACT, V113, P59 CHUMAKOV AI, 1997, PHYS REV B, V56, P10758 CHUMAKOV AI, 1996, PHYS REV B, V54, PR9596 CHUMAKOV AI, 1996, PHYS REV LETT, V76, P4258 COUSSEMENT R, 1996, PHYS REV B, V54, P16003 DEAK L, 1994, HYPERFINE INTERACT, V92, P1083 DEAK L, 1996, PHYS REV B, V53, P6158 EIBSCHUTZ M, 1987, PHYS REV B, V35, P8714 FEHRENBACHER R, 1993, PHYS REV LETT, V70, P3471 FELNER I, 1995, SUPERCOND SCI TECH, V8, P121 GERDAU E, 1985, PHYS REV LETT, V54, P835 GHOSH VJ, 1995, APPL SURF SCI, V85, P187 GUAN WY, 1993, PHYSICA C, V209, P19 GUILLAUME M, 1994, J PHYS-CONDENS MAT, V6, P7963 HA DH, 1998, PHYSICA C, V302, P299 HARP GR, 1990, PHYS REV LETT, V65, P1012 IQBAL Z, 1994, PHYS REV B, V49, P12322 KHOMSKII D, 1994, PHYSICA B, V199, P328 KLENCSAR Z, 1998, PHYSICA C, V304, P124 KLENCSAR Z, UNPUB PHYS REV LETT KOHN VG, 1998, PHYS REV B, V58, P8437 KORECKI P, 1999, PHYS REV B, V59, P6139 KORECKI P, 1997, PHYS REV LETT, V79, P3518 KRAMER MJ, 1997, PHYS REV B, V56, P5512 LABBE C, IN PRESS P 34 ZAK SC LANGMUIR I, 1935, KOLLOID Z, V73, P257 LATKA K, 1990, PHYSICA C, V171, P287 MAEDA H, 1988, JPN J APPL PHYS PT 2, V27, P209 MAREK T, 1997, MATER SCI FORUM, V255-, P686 MOOLENAAR AA, 1996, PHYSICA C, V267, P279 MOSSBAUER RL, 1958, Z PHYS, V151, P124 NAGY DL, 1997, CONDENSED MATTER STU, P17 NAGY DL, 1992, HYPERFINE INTERACT, V71, P1349 NAGY DL, 1999, NATO ASI 3 HIGH TECH, V66, P323 NAROZHNYI VN, 1999, PHYS REV LETT, V82, P461 NIEVA G, 1991, PHYS REV B, V44, P6999 NORTON DP, 1991, PHYS REV LETT, V66, P1537 ODEURS J, 1998, HYPERFINE INTERACT, V113, P455 PARK M, 1996, PHYSICA C, V259, P43 PAULSEN H, 1999, PHYS REV B, V59, P975 POOLE CP, 1995, SUPERCONDUCTIVITY REN YT, 1993, PHYSICA C, V213, P224 ROBERTS GG, 1985, ADV PHYS, V34, P475 SALDIN DK, 1990, PHYS REV LETT, V64, P1270 SCHULTZ PJ, 1988, REV MOD PHYS, V60, P701 SETO M, 1995, PHYS REV LETT, V74, P3828 SETTE F, 1995, PHYS REV LETT, V75, P850 SHENG ZZ, 1988, NATURE, V332, P55 SMIRNOV GV, 1996, HYPERFINE INTERACT, V97-8, P551 SMIRNOV GV, 1997, PHYS REV B, V55, P5811 SODERHOLM L, 1987, NATURE, V328, P604 STADNIK ZM, 1991, PHYS REV B, V44, P12552 STURHAHN W, 1995, PHYS REV LETT, V74, P3832 SZOKE A, 1986, AIP C P, V147 TEGZE M, 1991, EUROPHYS LETT, V16, P41 TEGZE M, 1996, NATURE, V380, P49 TEGZE M, 1999, PHYS REV LETT, V82, P4847 TOMKOWICZ Z, 1991, PHYSICA C, V174, P71 VANVEEN A, 1997, MATER SCI FORUM, V255-, P76 VANVEEN A, 1990, SLOW POSITRON BEAMS, P171 VERTES A, 1990, MOSSBAUER SPECTROSCO VERTES A, 1979, MOSSBAUER SPECTROSCO WORTMANN G, 1988, PHYS LETT A, V126, P434 WORTMANN G, 1990, SOLID STATE COMMUN, V75, P981 XU ZA, 1997, PHYSICA C, V282, P1197 ZHANG XW, 1995, JPN J APPL PHYS, V34, P330 ZOU Z, 1999, PHYS REV LETT, V82, P462 ZOU ZG, 1997, JPN J APPL PHYS 2, V36, PL18 TC 0 BP 241 EP 253 PG 13 JI J. Radioanal. Nucl. Chem. PY 2000 PD JAN VL 243 IS 1 GA 338JA J9 J RADIOANAL NUCL CHEM UT ISI:000088414700032 ER PT J AU Nagy, DL Bottyan, L Deak, L Szilagyi, E Spiering, H Dekoster, J Langouche, G TI Synchrotron Mossbauer reflectometry SO HYPERFINE INTERACTIONS NR 34 AB Grazing incidence nuclear resonant scattering of synchrotron radiation can be applied to perform depth-selective phase analysis and to determine the isotopic and magnetic structure of thin films and multilayers. Principles and recent experiments of this new kind of reflectometry are briefly reviewed. Methodological aspects are discussed. Model calculations demonstrate how the orientations of the sublattice magnetisation in ferro- and antiferromagnetic multilayers affect time-integral and time-differential spectra. Experimental examples show the efficiency of the method in investigating finite-stacking, in-plane and out-of-plane anisotropy and spin-flop effects in magnetic multilayers. CR AFANASEV AM, 1965, ZH EKSP TEOR FIZ, V21, P215 ALP EE, 1993, PHYS REV LETT, V70, P3351 ANDREEVA MA, 1999, J ALLOY COMPD, V286, P322 BARON AQR, 1994, PHYS REV B, V50, P10354 BERNSTEIN S, 1963, PHYS REV, V132, P1625 BORN M, 1970, PRINCIPLES OPTICS, P51 BOTTYAN L, 1998, HYPERFINE INTERACT, V113, P295 BOTTYAN L, 1999, UNPUB CARBONE C, IN PRESS CHUMAKOV AI, 1999, HYPERFINE INTERACT, V123, P427 CHUMAKOV AI, 1993, PHYS REV LETT, V71, P2489 DEAK L, 1999, CONDENSED MATTER STU, P151 DEAK L, 1994, HYPERFINE INTERACT, V92, P1083 DEAK L, 1996, PHYS REV B, V53, P6158 FERMI E, 1946, PHYS REV, V70, P103 GROTE M, 1991, EUROPHYS LETT, V14, P707 HANNON JP, 1985, PHYS REV B, V32, P5068 IRKAEV SM, 1993, NUCL INSTRUM METH B, V74, P545 KIESSIG H, 1931, ANNLN PHYS, V10, P715 KOHLHEPP J, 1997, PHYS REV B, V55, PR696 KULCSAR K, 1971, P INT C MOSSB SPECTR, P594 LAX M, 1951, REV MOD PHYS, V23, P287 MAJOR M, 1999, CONDENSED MATTER STU, P165 NAGY DL, 1997, CONDENSED MATTER STU, P17 NAGY DL, 1992, HYPERFINE INTERACT, V71, P1349 NAGY DL, 1999, MOSSBAUER SPECTROSCO, P323 NIESEN L, 1998, PHYS REV B, V58, P8590 NOTERMANN FC, 1992, PHYS REV B, V46, P10847 ROHLSBERGER R, 2000, HYPERFINE INTERACT, V125, P69 SMIRNOV GV, 1996, HYPERFINE INTERACT, V97-8, P551 SPIERING H, 2000, HYPERFINE INTERACT, V125, P197 SPIERING H, 1985, HYPERFINE INTERACT, V24, P737 TOELLNER TS, 1995, PHYS REV LETT, V74, P3475 WANG RW, 1994, PHYS REV LETT, V72, P920 TC 0 BP 353 EP 361 PG 9 JI Hyperfine Interact. PY 2000 VL 126 IS 1-4 GA 323TL J9 HYPERFINE INTERACTIONS UT ISI:000087581000053 ER PT J AU Deak, L Bayreuther, G Bottyan, L Gerdau, E Korecki, J Kornilov, EI Lauter, HJ Leupold, O Nagy, DL Petrenko, AV Pasyuk-Lauter, VV Reuther, H Richter, E Rohloberger, R Szilagyi, E TI Pure nuclear Bragg reflection of a periodic Fe-56/Fe-57 multilayer SO JOURNAL OF APPLIED PHYSICS NR 22 AB Grazing incidence nuclear multilayer diffraction of synchrotron radiation from a periodic stack of alternating Fe-56 and Fe-57 layers was observed. Resonant layer fraction, substrate size, flatness, and surface roughness limits were optimized by previous simulations. The isotopic multilayer (ML) sample of float glass/Fe-57(2.25 nm)/[Fe-56(2.25 nm)/Fe-57(2.25 nm)]X15/Al(9.0 nm) nominal composition was prepared by molecular beam epitaxy at room temperature. Purity structure and lateral homogenity of the isotopic ML film was characterized by magnetometry, Auger electron, Rutherford backscattering, and conversion electron Mossbauer spectroscopies. The isotopic ML structure was investigated by neutron and synchrotron Mossbauer reflectometry. Surface roughness of about 1 nm of the flat substrate (curvature radius > 57 m) was measured by scanning tunneling microscopy and profilometry. A pure nuclear Bragg peak appeared in synchrotron Mossbauer reflectometry at the angle expected from neutron reflectometry while no electronic Bragg peak was found at the same position by x-ray reflectometry. The measured width of the Bragg peak is in accordance with theoretical expectations. (C) 1999 American Institute of Physics. [S0021-8979(99)09201-4]. CR BARON AQR, 1994, PHYS REV B, V50, P10354 BORN M, 1970, PRINCIPLES OPTICS, P51 BOTTYAN L, 1998, HYPERFINE INTERACT, V113, P295 CHUMAKOV AI, COMMUNICATION CHUMAKOV AI, 1991, JETP LETT, V54, P271 CHUMAKOV AI, 1992, JETP LETT+, V55, P509 CHUMAKOV AI, 1993, PHYS REV LETT, V71, P2489 DEAK L, 1993, CONDENSED MATTER STU, P269 DEAK L, 1994, HYPERFINE INTERACT, V92, P1083 DEAK L, 1996, PHYS REV B, V53, P6158 HANNON JP, 1985, PHYS REV B, V32, P6363 HANNON JP, 1984, PHYS REV B, V32, P5068 KABANNIK VA, 1989, VERSION NUCL RESONAN KIKUTA S, 1989, REV SCI INSTRUM, V60, P2126 KOMEEV DA, 1992, SURFACE XRAY NEUTRON, P213 KOTAI E, 1994, NUCL INSTRUM METH B, V85, P588 NAGY DL, 1992, HYPERFINE INTERACT, V71, P1349 PASZTI F, 1990, NUCL INSTRUM METH B, V47, P187 PENFOLD J, 1990, J PHYS-CONDENS MAT, V2, P1369 ROHLSBERGER R, 1993, J APPL PHYS, V74, P1933 TOELLNER TS, 1995, PHYS REV LETT, V74, P3475 TRAMMELL GT, 1977, AIP C P, V38, P46 TC 2 BP 1 EP 7 PG 7 JI J. Appl. Phys. PY 1999 PD JAN 1 VL 85 IS 1 GA 148DM J9 J APPL PHYS UT ISI:000077489200001 ER PT J AU Bottyan, L Dekoster, J Deak, L Baron, AQR Degroote, S Moons, R Nagy, DL Langouche, G TI Layer magnetization canting in Fe-57/FeSi multilayer observed by synchrotron Mossbauer reflectometry SO HYPERFINE INTERACTIONS NR 13 AB Synchrotron Mossbauer reflectometry and GEMS results on a [Fe- 57(2.55 nm)/FeSi (1.57 nm)](10) multilayer (ML) on a Zerodur substrate are reported. CEMS spectra are satisfactorily fitted by alpha-Fe and an interface layer of random alpha-(Fe, Si) alloy of 20% of the 57Fe layer thickness on both sides of the individual Fe layers. Kerr loops show a fully compensated AF magnetic layer structure. Prompt X-ray reflectivity curves show the structural ML Bragg peak and Kiessig oscillations corresponding to a bilayer period and total film thickness of 4.12 and 41.2 nm, respectively. Grazing incidence nuclear resonant Theta-2 Theta scans and time spectra (E = 14.413 keV, lambda = 0.0860 nm) were recorded in different external magnetic fields (0 < B-ext < 0.95 T) perpendicular to the scattering plane. The lime integral delayed nuclear Theta-2 Theta scans reveal the magnetic ML period doubling. With increasing transversal external magnetic field, the antiferromagnetic ML Bragg peak disappears due to Fe layer magnetization canting, the extent of which is calculated from the fit of the time spectra and the Theta-2 Theta scans using an optical approach. In a weak external field the Fe layer magnetization directions are neither parallel with nor perpendicular to the external field. We suggest that the interlayer coupling in [Fe/FeSi](10) varies with the distance from the substrate and the ML consists of two magnetically distinct regions, being of ferromagnetic character near substrate and antiferromagnetic closer to the surface. CR BOTTYAN L, IN PRESS CHAIKEN A, 1996, PHYS REV B, V53, P5518 DEAK L, 1996, PHYS REV B, V53, P6158 DEKOSTER J, 1995, MATER RES SOC SYMP P, V382, P253 FULLERTON EE, 1995, PHYS REV B, V53, P5112 KOHLHEPP J, 1997, PHYS REV B, V55, PR696 MATTSON JE, 1993, PHYS REV LETT, V71, P185 NAGY DL, 1992, HYPERFINE INTERACT, V71, P1349 NAGY DL, 1997, P 32 ZAK SCH PHYS ZA RUFFER R, 1996, HYPERFINE INTERACT, V97-8, P589 SAITO Y, 1996, JPN J APPL PHYS 2, V35, PL100 STEARNS MB, 1963, PHYS REV, V129, P1136 TOSCANO S, 1992, J MAGN MAGN MATER, V114, PL6 TC 6 BP 295 EP 301 PG 7 JI Hyperfine Interact. PY 1998 VL 113 IS 1-4 GA 124CT J9 HYPERFINE INTERACTIONS UT ISI:000076164300021 ER PT S AU Szilagyi, E Bottyan, L Deak, L Gerdau, E Gittsovich, VN Grof, A Kotai, E Leupold, O Nagy, DL Semenov, VG TI Corrosion depth profiles by Rutherford backscattering spectrometry and synchrotron X-ray reflectometry SO MATERIALS SCIENCE APPLICATIONS OF ION BEAM TECHNIQUES NR 6 AB Rutherford backscattering and synchrotron x-ray reflectometry was used to analyse the depth profile of elements in a sputtered iron thin film of originally 20 nm thickness following corrosion heat treatments. An ''up to self- consistency'' simultaneous evaluation of both kinds of spectra allowed for accurate determination both elemental composition and thickness of the sub-layers. Different iron oxide and oxi- hydroxide layers were identified on top of the iron layer depending on the treatment. An oxide layer of overall composition close to Fe2O3 was also observed at the iron/glass interface. CR BORN M, 1978, PRINCIPLES OPTICS COWLEY RA, 1987, J PHYS D APPL PHYS, V20, P61 HANNON JP, 1994, PHYS REV B, V32, P5068 KOTAI E, 1994, NUCL INSTRUM METH B, V85, P588 NAGY DL, 1992, HYPERFINE INTERACT, V71, P1349 NEVOT L, 1980, REV PHYS APPL, V15, P761 TC 0 BP 365 EP 368 PG 4 SE MATERIALS SCIENCE FORUM PY 1997 VL 248- GA BJ36H J9 MATER SCI FORUM UT ISI:A1997BJ36H00066 ER PT J AU Deak, L Bottyan, L Nagy, DL Spiering, H TI Coherent forward-scattering amplitude in transmission and grazing incidence Mossbauer spectroscopy SO PHYSICAL REVIEW B-CONDENSED MATTER NR 19 AB The theory of both transmission and grazing incidence Mossbauer spectroscopy is reanalyzed. Starting with the nuclear susceptibility tensor a common concise first-order perturbation formulation is given by introducing the forward-scattering amplitude into an anisotropic optical scheme. Formulas of Blume and Kistner as well as those of Andreeva are rederived for the forward-scattering and grazing incidence geometries, respectively. Limitations of several previously intuitively introduced approximations are pointed out. The grazing incidence integral propagation matrices are written in a form built up from 2 x 2 matrix exponentials which is particularly suitable for numerical calculations and practical fitting of both energy domain (conventional source experiment) and time domain (synchrotron radiation experiment) Mossbauer spectra. CR AFANASEV AM, 1965, ZH EKSP TEOR FIZ, V21, P215 ANDREEVA MA, 1982, MESSBAUEROVSKAYA GAM ANDREEVA MA, 1986, POVERKHNOST, V9, P145 ANDREEVA MA, 1994, SOV PHYS JETP, V78, P965 ANDREEVA MA, 1986, VESTN MOSK U FIZ AS+, V27, P57 BLUME M, 1968, PHYS REV, V171, P417 BORZDOV GN, 1976, ZH PRIKL SPEKTROSK, V25, P526 FEDOROV FI, 1976, TEORIYA GIROTROPII FORST JC, 1985, APPL PHYS LETT, V47, P581 HANNON JP, 1969, PHYS REV, V186, P306 HANNON JP, 1968, PHYS REV, V169, P315 HANNON JP, 1985, PHYS REV B, V32, P5068 HANNON JP, 1985, PHYS REV B, V32, P6363 IRKAEV SM, 1993, NUCL INSTRUM METH B, V74, P545 IRKAEV SM, 1993, NUCL INSTRUM METH B, V74, P554 LAX M, 1951, REV MOD PHYS, V23, P287 NAGY DL, 1992, HYPERFINE INTERACT, V71, P1349 ROHLSBERGER R, 1994, THESIS U HAMBURG SPIERING H, 1985, HYPERFINE INTERACT, V24, P737 TC 11 BP 6158 EP 6164 PG 7 JI Phys. Rev. B-Condens Matter PY 1996 PD MAR 1 VL 53 IS 10 GA TZ773 J9 PHYS REV B-CONDENSED MATTER UT ISI:A1996TZ77300030 ER PT J AU DEAK, L BOTTYAN, L NAGY, DL TI CALCULATION OF NUCLEAR RESONANT SCATTERING SPECTRA OF MAGNETIC MULTILAYERS SO HYPERFINE INTERACTIONS NR 11 AB We report on calculations of the angle- and time-dependent photon reflectivity of multilayers using the technique of characteristic matrices. Spectra of Fe-56/Fe-57 and Cr/Fe multilayers are calculated under various conditions. The parameters of the multilayers are optimized for suitable test samples of reflectometry measurements. CR BLUME M, 1968, PHYS REV, V171, P417 BORN M, 1970, PRINCIPLES OPTICS, P51 CHUMAKOV AI, 1991, PISMA ESKP TEOR FIZ, V53, P258 DEAK L, 1993, 18TH P ZAK SCH PHYS, P269 FOLKERTS W, 1992, J APPL PHYS, V71, P362 HANNON JP, 1969, PHYS REV, V186, P306 HANNON JP, 1985, PHYS REV B, V32, P5068 HANNON JP, 1985, PHYS REV B, V32, P6363 KAGAN Y, 1979, J PHYS C SOLID STATE, V12, P615 LAX M, 1951, REV MOD PHYS, V23, P287 NAGY DL, 1992, HYPERFINE INTERACT, V71, P1349 TC 8 BP 1083 EP 1088 PG 6 JI Hyperfine Interact. PY 1994 VL 92 IS 1-4 GA QB952 J9 HYPERFINE INTERACTIONS UT ISI:A1994QB95200024 ER