Modification of a refocused I-S INEPT into a 2D HSQC sequence,and use of States-TPPI quad detection INEPT 2-spin INEPT order 31 φ12 φ1=6-x φ2=x,x,-x,-x φ31=x-七-6x G: 2LS±21S2±2lS2 /4s φ31 φ2 φ1=6x +States-TPPI =1(0)+(ni-1)/sw1 2=xx,-x,-x G φ31=北，-6-x,x +States-TPPl 21S.21-S.2S,21Scos(os1)21S.215 ×cos(元J11) -21-Sx sin(os n) ×cos(πJt)