In recent years Dilano Saldin's
research has focused on the
development of methods for the solution of inverse scattering problems in
the recovery of the atomic structure of materials from x-ray and electron
diffraction data. In the use of low energy electron probes for the determination
of surface structures, Saldin's group has pioneered the technique of holographic
low energy electron diffraction, which directly reconstructs a 3D picture of
adsorption sites of atoms. The 3D holographic image is displayed by
state-of-the-art computer graphics techniques. Similar methods have been
developed for photoelectron diffraction, where the probe electrons are generated
by the absorption of x-ray photons (typically produced by a synchrotron) within
the material to be studied. This enables 3D images around chemically distinct
sites to be generated independently.
Synchrotron x-rays may also be used more directly to produce x-ray
diffraction patterns of surfaces. In surface x-ray diffraction, intensity
measurements along rods in reciprocal space gives information about the surface
electron density. Work is in progress on developing methods for the direct
recovery of this surface electron distribution from the diffraction data, using
a combination of holographic and other methods for phasing that have been studied
in optics, astronomy and related fields. Similar ideas are
being applied for the development of direct methods for the x-ray
crystallography of macromolecules, such as proteins.
Work is also in progress on theories and related computer codes for the
interpretation of other synchrotron radiation experiments such as x-ray
absorption and photoemission on a variety of materials, ranging from the
perovskite high temperature superconductors to hydrocarbon molecules on catalyst
surfaces.
Saldin is the Associate Executive Editor of Surface Review and
Letters . He was a Junior Fellow at Oxford and has served as a member
of the Peer Review Panel for the Office of Basic Energy Sciences, U.S.
Department of Energy. He is the author of over 100 publications and the holder
of 2 U.S. patents. Saldin's work is currently supported by the
National Science Foundation and the U.S. Department of Energy..
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