Development of a High Resolution X-Ray Analyzer for Transition Metal Oxide
Research and Education
Investigators: Trevor A. Tyson, New Jersey
Institute of Technology (tyson@adm.njit.edu,
tel: 973-642-4681)
Wolfgang Caliebe, National Synchrotron Light Source, BNL
Chi-Chang Kao, National Synchrotron Light Source, BNL (kao@bnl.gov,
tel: 631-344-4494)
Funding Source: National Science
Foundation, Major Research Instrumentation/Instrumentation for Materials
Research Grant DMR
0216858
Contacts for Access: Trevor A. Tyson, New Jersey Institute of Technology (tyson@adm.njit.edu,
tel: 973-642-4681)
Chi-Chang Kao, National Synchrotron Light Source, BNL (kao@bnl.gov, tel: 631-344-4494)
Abstract
High-resolution x-ray emission
spectroscopy based at electron storage rings at national laboratories has
developed into a powerful tool to examine the chemistry of metal atoms. This
tool can be applied to study the valence of metal sites in protein molecules in
order to understand their function. In addition, this approach can be used to
study light atom such as carbon without the need for a high vacuum system.
However, its use has been limited to specialists because of the lack of
dedicated systems. With this award from the Instrumentation for Materials
Research program and the Major Research Instrumentation program scientists at
the New Jersey Institute of Technology (NJIT) will develop a high resolution
x-ray analyzer which will be stationed at the National Synchrotron Light Source
(NSLS) in Brookhaven National Laboratory. Stationing the system at the NSLS will
make the system available to a broad range of users in fields as diverse of
chemistry, biology, geology and physics. At all levels of the construction and
research conducted with this analyzer graduate students will be involved. The
proposed instrument will have a broad impact through the education of graduate
and undergraduate students based on its use in laboratory courses. In addition,
the instrument will be utilized as a chemical analysis tool in a transition
metal oxide preparation and characterization workshop for Newark area high
school students conducted at the NJIT. This will serve to develop scientific
literacy and to directly influence students from underrepresented groups to
pursue careers in science.
Summer 2003 Full System Test of the High Resolution
X-Ray Spectrometer at X21A (NSLS)
Fig. 1. First Mn Kb spectrum collected with
new spectrometer.
2(a)
2(b)
Fig. 2. Spectrometer
with He bag in place (temporary- to be replaced by a sealed Al enclosure). 2(a) gives a full view while 2(b) shows the
sample
and ion chamber used to measure I0.
Fig. 3. Full picture of spectrometer.
(micro
radian accuracy) in both the horizontal (theta) and vertical planes (chi).
Fig. 5. Measurement of the Mn Kb
spectrum of MnF2 with a 2 sec/point sampling rate. The upper curve on the left is the
expanded higher energy spectrum.
Fig. 6. Carbon K-Edge x-ray absorption measured with the
spectrometer This system can measure
the absorption edges of light
atoms with bulk sensitivity as an x-ray Raman signal. The energy resolution is currently ~0.5 eV. This can be significantly improved
with the construction of better x-ray mirrors.