Dipolar exchange, relaxation-induced

A second dipolar effect in CODEX is the relaxation-induced dipolar exchange due to dipolar couplings to heteronuclei,82 83 in particular 14N and 15N, which undergo significant longitudinal relaxation during tm. The relaxation removes a heteronuclear coherence term from the density operator and thus reduces the stimulated echo. This effect is described in detail in ref. 83. 

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