Frequency dependence of EPR signal intensity, 248 MHz to 1.4 GHz.

The electron paramagnetic resonance pulsed free induction decay (FID) of a degassed solution of a triaryl methyl radical, methyl tris(8-carboxy-2,2,6,6-tetramethyl(-d3)-benzo[1,2-d:4,5-d']bis(1,3)dithiol-4-yl) tripotassium salt, 0.2 mM in H2O, was measured at VHF (247.5 MHz) and L-band (1.40 GHz). The calculated and observed FID signal amplitudes (in millivolts) agreed within 1 and 6%, and the ratio of the normalized FID signals at the two frequencies agreed within 5%. The FID decay time constant was 2.7 micros at both frequencies.

[1]  W. Mims.  Electron Echo Methods in Spin Resonance Spectrometry , 1965 .

[2]  J. Hyde,et al.  Loop-gap resonators , 1986 .

[3]  J. Freed,et al.  Spectral rotation in pulsed ESR spectroscopy , 1986 .

[4]  A. Hoff,et al.  Advanced EPR : applications in biology and biochemistry , 1989 .

[5]  Howard J. Halpern,et al.  Imaging radio frequency electron‐spin‐resonance spectrometer with high resolution and sensitivity for in vivo measurements , 1989 .

[6]  Sankaran Subramanian,et al.  Radiofrequency FT EPR Spectroscopy and Imaging , 1993 .

[7]  W. Froncisz,et al.  Relative Benefits of Overcoupled Resonators vs Inherently Low-Q Resonators for Pulsed Magnetic Resonance , 1994 .

[8]  George A. Rinard,et al.  A 1–2 GHz pulsed and continuous wave electron paramagnetic resonance spectrometer , 1996 .

[9]  G. Rinard,et al.  Dispersion and Superheterodyne EPR Using a Bimodal Resonator , 1996 .

[10]  G. Rinard,et al.  Easily Tunable Crossed-Loop (Bimodal) EPR Resonator , 1996 .

[11]  R Murugesan,et al.  In vivo imaging of a stable paramagnetic probe by pulsed‐radiofrequency electron paramagnetic resonance spectroscopy , 1997, Magnetic resonance in medicine.

[12]  James B. Mitchell,et al.  A broadband pulsed radio frequency electron paramagnetic resonance spectrometer for biological applications , 1998 .

[13]  J S Petersson,et al.  EPR and DNP properties of certain novel single electron contrast agents intended for oximetric imaging. , 1998, Journal of magnetic resonance.

[14]  Giuseppe Placidi,et al.  A Submicrosecond Resonator and Receiver System for Pulsed Magnetic Resonance with Large Samples , 1998 .

[15]  Alecci,et al.  A Radiofrequency (220-MHz) Fourier Transform EPR Spectrometer , 1998, Journal of magnetic resonance.

[16]  Spatially resolved magnetic resonance : methods, materials, medicine, biology, rheology, geology, ecology, hardware , 1998 .

[17]  G. Rinard,et al.  Absolute EPR spin echo and noise intensities. , 1999, Journal of magnetic resonance.

[18]  J. Harbridge,et al.  Frequency dependence of EPR signal-to-noise. , 1999, Journal of magnetic resonance.

[19]  R Murugesan,et al.  High-speed data acquisition system and receiver configurations for time-domain radiofrequency electron paramagnetic resonance spectroscopy and imaging. , 1999, Journal of magnetic resonance.

[20]  G. Rinard,et al.  An L-band crossed-loop (Bimodal) EPR resonator. , 2000, Journal of magnetic resonance.

[21]  H. Halpern,et al.  Electron spin relaxation of triarylmethyl radicals in fluid solution. , 2001, Journal of magnetic resonance.

[22]  James B. Mitchell,et al.  Time-Domain Radio Frequency EPR Imaging , 2003 .

[23]  G. Rinard,et al.  Frequency Dependence of EPR Sensitivity , 2004 .