MOSHE DEUTSCH, PROFESSOR

Telephone972-3-5318476

Fax972-3-5353298

email deutsch@alon.cc.biu.ac.il ( and moshe@solids.phy.bnl.gov )

Topics of research:

  1. Experimental studies of condensed matter by X-Ray techniques
  2. Application of synchrotron radiation in x-ray spectroscopy and diffraction
  3. Surface structure of liquids, soft condensed matter and solids
  4. X-ray spectroscopy of single and multielectronic processes
  5. Bonding and charge density distribution in crystals
  6. Perfect crystal x-ray optical elements and devices
  7. Non destructive evaluation in industry and medicine by x-ray techniques

List of recent publications

Recent Abstracts

  1. X.Z. Wu(1), E.B. Sirota(1), S.K. Sinha(1), B. M. Ocko(3), and M. Deutsch(2,3)

    Surface Crystallization of Liquid Normal-Alkanes

    (1) Corporate Research Science Laboratory, Exxon Research and Engineering Co., Route 22 East, Annandale, NJ 08801

    (2) Physics Department, Bar Ilan University, Ramat Gan 52900, Israel

    (3) Physics Department Brookhaven National Laboratory, Upton, NY 11973

    X-ray scattering and surface tension measurements reveal the formation of a crystalline monolayer on the surface of liquid n-alkanes at about 3 C above the bulk solidification temperature. The molecules in the monolayer are hexagonally packed, and oriented normal to the surface. The single solid monolayer persists down to the bulk solidification temperature, thus exhibiting a very limited partial wetting.

  2. Z.W. Lu(1), Alex Zunger(1) and Moshe Deutsch(2). The electronic charge distribution in crystalline diamond, silicon, and germanium: theory versus experiment. Phys. Rev. B 47, 9385 (1993).

    (1) National Renewable Energy Laboratory, Golden, Colorado 80401

    (2) Department of Physics, Bar Ilan University, Ramat-Gan, 52900, Israel

    Recent refinement studies of a consolidated set of Si structure factors have produced information on the Si charge density with an unprecedented level of accuracy, unmatched by any other crystallographic study to date. In this work we examine the extent to which an accurate implementation of the local density formalism can describe the charge distribution in silicon, as well as that of the experimentally less refined data on diamond and germanium. Results of a refinement study of recent germanium and diamond measurements are presented and compared with the ab-initio calculations. Our ab-initio calculated structure factors for Si show a 2-5 fold improvement in the R-factor over previous local density calculations. We describe in detail, total, valence, and deformation charge density maps for C, Si, and Ge. We analyze the effects of high- momentum components (currently outside the range of the high-precision measurements) as weas dynamic structure factors on the ensuing charge density maps.

  3. B.M. Ocko(1), X.Z. Wu(2), E.B. Sirota(2), S.K. Sinha(2), and M. Deutsch(3). An X-ray Reflectivity Study of Thermal Capillary Waves On Liquid Surfaces. Phys. Rev. Lett. 72, 242 (1994).

    (1) Physics Department Brookhaven National Laboratory, Upton, NY 11973

    (2) Corporate Research Laboratory, Exxon Research and Engineering Co., Route 22 East, Annandale, NJ 08801

    (3) Physics Department, Bar Ilan University, Ramat Gan 52900, Israel

    X-ray reflectivity measurements have been carried out at the liquid/vapour interface of normal alkanes. The reflectivities over a large temperature range of different chain lengths (C20 and C36) provides a critical test of the various capillary wave models. Our data is most consistent with the hybrid model which allows for a molecular size dependent cutoff qmax for the capillary waves and an intrinsic interface width sigma.

  4. Shay Gueron(1) and Moshe Deutsch(2). Single-projection radiography for non- circular symmetries: a generalization of the Abel transform method. J. Appl. Phys., in press (1995).

    (1) Department of Mathematics, Technion, Haifa 32000, Israel

    (2) Department of Physics, Bar-Ilan University, Ramat-Gan 52900, Israel

    We present a new method which extends the use of the single projection radiographic Abel method, hitherto applicable only to objects of circular cross-sections and elliptical cross-sections, to objects having general, non-circular symmetries. This is done by developing a new integral equation that is similar in applications to Abel's equation, and includes it as a special case. The use of the new equation is discussed for objects having a smooth and convex cross-section boundary (e.g., elliptic), a piecewise smooth convex boundary (e.g. bi-parabolic) and a boundary with regions of zero curvature (e.g., polygons). Specific examples are given for each of these three classes, and analytic inverses are calculated for these cases. Also, numerical inversion of the integral equation is given, showing satisfactory results. We show that in contrast to Abel's equation in many cases the kernel of the integral equation is non-singular. Consequently, fairly simple inversion techniques are sufficient. Finally, the azimuthal variation of the transmitted intensity is employed to provide a convenient and fast NDE test of the deviation of the radiographed object from a prescribed symmetry.

  5. M. Deutsch(1), G. Hoelzer(2), J. Haertwig(3), J. Wolf(4), M. Fritsch(2) and E. Foerster(3). The Kalpha and Kbeta x-ray emission spectra of copper. Phys. Rev. A 51, 283 (1995).

    (1) Physics Department, Bar-Ilan University, Ramat-Gan 52900, Israel.

    (2) Max-Planck-Arbeitsgruppe ``Roentgenoptik'' an der Friedrich-Schiller- Universitat Jena, Max-Wien-Platz 1, D-07743 Jena, Germany.

    (3) ESRF, B.P. 220, F-38043 Grenoble Cedex, France.

    (4) Institut fur Optik und Quantenelektronik, Friedrich-Schiller-Universitat Jena, Max-Wien-Platz 1, D-07743 Jena, Germany.

    The Kalpha1,2 and Kbeta1,3 spectra of copper were measured using double- and single- crystal diffractometers whose finite resolution effects were carefully characterized and corrected for. A phenomenological resolution of the spectra into lorentzians is given, yielding excellent R-factors close to 1 percent. Fits to our detailed relativistic Dirac-Fock and non- relativistic Hartree-Fock ab-initio calculations reveal that the line shapes can be accounted for by the diagram and the single 3d spectator hole transitions only, with R-factors of 3-5 percent. The contribution of the 3d spectator transitions to both spectra is 26-30 percent. The Kalpha spectrum may also contain a small, 0.5 percent, contribution from the 3p spectator transition. The fit residuals of the Kbeta spectrum show systematic deviations in the vicinity of the beta' feature, which may be due to exchange interactions or plasmon excitations. Contributions of similar origins to the Kalpha spectrum were not detected. Line widths, energies and intensities are reported, some of which for the first time, for the raw as well as the fit-resolved spectra, and critically compared with previous data, where available.

  6. M.J. Regan(1), E.H. Kawamoto(1), S. Lee(1), P.S. Pershan(1), N. Maskil(2), M. Deutsch(2), O.M. Magnussen(3), B.M. Ocko(3), and L.E. Berman. Surface Layering in Liquid Gallium: An X-Ray Reflectivity Study. Phys. Rev. Lett. 75, 2498 (1995).

    (1) Div. of Applied Sciences and Dept. of Physics, Harvard University, Cambridge, MA 02138.

    (2) Physics Dept., Bar-Ilan University, Ramat-Gan 52900, Israel.

    (3) Physics Dept., Brookhaven National Laboratory, Upton, NY 11973.

    (4) NSLS, Brookhaven National laboratory, Upton, NY 11973.

    Surface induced atomic layering in liquid gallium has been observed using x-ray reflectivity, ultra high vacuum conditions and sputter clean surfaces. Reflectivity data, collected on a supercooled liquid sample to momentum transfers as large as qz=3.0 (1/A) exhibit a strong maximum near 2.4 (1/A) indicating a layer spacing that is comparable to its atomic dimensions. The amplitude of the electron density oscillations decays with a characteristic length of 6 A. This is unexpectedly twice that of recent results for Hg, and the difference may be related to covalent bonding or supercooling.