C. Anderson. Evans

Use of the integral of saturation transfer electron paramagnetic resonance spectra to determine molecular rotational correlation times. Slowly tumbling spin labels in the presence of rapidly tumbling spin labels

Abstract A correlation of the integral of saturation transfer EPR spectra with the rotational tumbling rate of a slowly tumbling nitroxide has been determined. Since the integral or area under the ST-EPR spectrum of a rapidly tumbling nitroxide has a value very near zero, it is proposed that this correlation will be useful for determining rotational correlation times of slowly tumbling nitroxides “contaminated” with rapidly tumbling nitroxides. Some examples of such rotational tumbling rate determinations in model systems are given.