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New pulse schemes are presented for separation of integrals of partially resolved doublets using non-selective RF pulses. The separation is based on the evolution under the influence of chemical shift leading to two orthogonal magnetization components. The selection of one of these orthogonal signals is then achieved by retaining it in the transverse plane while converting the other into unobservable longitudinal magnetization. Alternatively, the desired signal is converted into longitudinal magnetization while the other signal is dephased using gradients. Subsequently, the longitudinal magnetization is converted to detectable signal. Experimental results are demonstrated, separately, using 1H and 13C NMR.

A method that combines sensitivity and a gradient-enhanced two-dimensional heteronuclear shift correlation experiment with constant-time evolution during the $t_1$ period is proposed for multiplicity editing of the spectra at natural $^1^3C$ abundance. In the resultant two-dimensional spectrum the cross-peaks of CH and $CH_3$ groups are negative whereas those of $CH_2$ groups are positive in sign. We demonstrate the technique on a small biomolecule. cyclosporin A. It is observed that the sensitivity of the new multiplicity editing experiment (named as CT-PFG-PEP-HSQC) is comparable with that of the conventional PFG-PEP-HSQC experiment and therefore the new scheme can be useful for routine applications.

Deuteron NMR studies of mixtures of nematic liquid crystals such as N-(p-ethoxybenzylidene)-p-n-butylaniline and trans-4-pentyl-4-(4-cyanophenyl)cyclohexane and the molecules dissolved therein show the coexistence of up to three different spectra at certain concentrations and temperatures. This is attributed to the coexistence of nematic and “induced” smectic phases.