Resonant x-ray reflectivity from a bromine-labeled
fatty acid Langnmir monolayer
Strzalka J, DiMasi E, Kuzmenko I, Gog T, Blasie JK
PHYSICAL REVIEW E
70 (5): Art. No. 051603 Part 1, NOV 2004
Resonant x-ray reflectivity exploits the energy dependence of atomic scattering
factors to locate resonant atoms within the electron density distribution
of thin films. We apply the technique to a monolayer of bromostearic acid
at the air/water interface. The data collection protocol employed cycles
through several energies in the vicinity of the bromine K absorption edge
and verifies that the energy dependencies observed are indeed resonant effects.
The analysis specifies the location of the Br atom with sub-angstrom precision
and must consider both the real and imaginary parts of the changes in the
scattering factor to be consistent with the known structure and stoichiometry
of this test case.