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X-ray spectroscopies are uniquely poised to describe the geometric and electronic structure of metalloenzyme active sites under a wide variety of sample conditions. UV/Vis (ultraviolet/visible) spectroscopy is a similarly well-established technique that can identify and quantify catalytic intermediates. The work described here reports the first simultaneous collection of full in situ UV/Vis and high-energy resolution fluorescence detected x-ray absorption spectra. Implementation of a fiber optic UV/Vis spectrometer and parabolic mirror setup inside the dual array valence emission spectrometer allowing for simultaneous measurement of microfluidic flow and mixing samples at the Photon-In Photon-Out X-ray Spectroscopy beamline is described, and initial results on ferricyanide and a dilute iron protein are presented. In conjunction with advanced microfluidic mixing techniques, this will allow for the measurement and quantification of highly reactive catalytic intermediates at reaction-relevant temperatures on the millisecond timescale while avoiding potential complications induced by freeze quenching samples.
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Developments in Mössbauer Spectrometry: From Instrumentation to High Pressure Studies on Spins and Phonons
Ph.D. thesis by Pedro Guzman, presenting work on a microminiature Mossbauer spectrometer for possible planetary missions, and work with a large spectrometer at a beamline at the Advanced Photon Source. The work at the advanced photon source showed the thermodynamic origin of the pressure-induced Invar effect in Fe-45%Ni as a balance between phonons and spins.
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- Award ID(s):
- 1904714
- PAR ID:
- 10640461
- Publisher / Repository:
- California Institute of Technology
- Date Published:
- Subject(s) / Keyword(s):
- Mössbauer, piezoelectric, Invar, Elinvar, entropy
- Format(s):
- Medium: X
- Institution:
- California Institute of Technology
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Dissertation:
- https://doi.org/10.7907/hyry-q484
