Investigation of the possibilities of measuring relaxation parameters by the EPR method within the framework of the concept of spin temperature

Procedures for measuring some relaxation parameters of uniformly and nonuniformly broadened systems by the EPR method in a high-temperature approximation are proposed. The theoretical consideration is based on the concept of spin temperature and Provotorov's equations. A trial field is used along with a saturating superhigh-frequency field. The measuring methods for the time of the transverse relaxation T₂ in the case of uniform broadening and some relaxation parameters or their combinations in the case of nonuniform broadening are based on measuring the frequency characteristics of the system when the absorption becomes zero at the frequency of the trial field. Institute of Physical and Organic Chemistry, National Academy of Sciences of Belarus, 13, Surganov Str., Minsk, 220072. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 2, pp. 266–270, March–April, 1999.