Faculty Collaboration Database

Rutile dielectric loop-gap resonator for X-band EPR spectroscopy of small aqueous samples. J Magn Reson 2019 Oct;307:106585

Date

09/10/2019

Pubmed ID

31499469

Pubmed Central ID

PMC6948142

DOI

10.1016/j.jmr.2019.106585

Scopus ID

2-s2.0-85071859156 (requires institutional sign-in at Scopus site)   10 Citations

Abstract

The performance of a metallic microwave resonator that contains a dielectric depends on the separation between metallic and dielectric surfaces, which affects radio frequency currents, evanescent waves, and polarization charges. The problem has previously been discussed for an X-band TE₀₁₁ cylindrical cavity resonator that contains an axial dielectric tube (Hyde and Mett, 2017). Here, a short rutile dielectric tube inserted into a loop-gap resonator (LGR) at X-band, which is called a dielectric LGR (dLGR), is considered. The theory is developed and experimental results are presented. It was found that a central sample loop surrounded by four "flux-return" loops (i.e., 5-loop-4-gap) is preferable to a 3-loop-2-gap configuration. For sufficiently small samples (less than 1 µL), a rutile dLGR is preferred relative to an LGR both at constant Λ (B₁/P_l) and at constant incident power. Introduction of LGR technology to X-band EPR was a significant advance for site-directed spin labeling because of small sample size and high Λ. The rutile dLGR introduced in this work offers further extension to samples that can be as small as 50  nL when using typical EPR acquisition times.

Author List

Mett RR, Sidabras JW, Anderson JR, Klug CS, Hyde JS

Authors

Candice S. Klug PhD Professor in the Biophysics department at Medical College of Wisconsin
Richard R. Mett PhD Adjunct Professor in the Biophysics department at Medical College of Wisconsin
Jason W. Sidabras PhD Assistant Professor in the Biophysics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Algorithms
Electromagnetic Fields
Electron Spin Resonance Spectroscopy
Equipment Design
Finite Element Analysis
Microwaves
Radio Waves
Titanium
Water