Constant-time periods with two-J evolution

In X-Y heteronuclear systems when evolution of both J_IX and J_XY couplings take place (d6=1/4J_IX and d4=1/4J_XY). If X and Y are homonuclear spins, then d6=d4=(2n+1)/4J_XY.

     

Evolution of X chemical shift: (t₁/2)+d6+(d4-d6)+(d5-d4)-(d5-t₁/2)=t₁
Evolution of J_IX coupling constant: (t₁/2)+d6-(d4-d6)-(d5-d4)+(d5-t₁/2)=2*d6
Evolution of J_XX' coupling constant: (t₁/2)+d6+(d4-d6)+(d5-d4)+(d5-t₁/2)=2*d5
Evolution of J_XY coupling constant:(t₁/2)+d6+(d4-d6)-(d5-d4)+(d5-t₁/2)=2*d4

Easy implementation on AVANCE spectrometers.