ABSTRACT
This chapter deals with spin–lattice () and transverse () relaxation and their mechanisms in the liquid state. -relaxation is sensitive to fast random motions (those close to the resonance frequency), whereas -relaxation is sensitive additionally to slow random motions (close to zero frequency). determines the saturation behaviour of the spectrum, whereas determines the Lorentzian linewidths; only for very fast motion do we get . Both depend on the hyperfine state of the nitroxide. A valuable summary is given in the concluding section of this chapter. Appendices O.3–O.6 given at the end of the book are directly relevant to this chapter.
