We present a detailed study on the integration of individual single-walled carbon nanotubes (SWNTs) within a lyotropic hexagonal liquid crystal (LC) for the first time. Two systems are studied in this work; in the first, the same surfactant is used for both the dispersion of the SWNTs and the formation of the LC. In the second system, we use different surfactants for the dispersion of SWNTs and LC formation. Light microscopy imaging combined with small-angle X-ray scattering (SAXS) indicates that the nanotubes (NTs) are well dispersed and aligned along the LC director. The macroscopic property, namely, the viscosity, is strongly enhanced by the presence of the NTs.

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Spin–lattice relaxation in a liquid containing protons in two different molecular environments can proceed by three different routes. There is a route to relaxation associated with each of the environments resulting from interactions between protons within that same environment. The third route to relaxation results from interaction between protons in different environments and is called cross relaxation. In such a system, the total spin–lattice relaxation decay determined by pulsed NMR will be the sum of two exponentials. Three relaxation rate constants are derived from such data. When cross relaxation arises entirely from dipole–dipole interaction in the extreme narrowing limit, these rate constants may be associated with the three routes to relaxation. (The cross-relaxation rate can always be identified, regardless of the mechanism.) To illustrate such relaxation behavior and the methods for obtaining three independent relaxation rates, 1-phenylpropyne was studied as a function of temperature.

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The microwave spectra of CH3C35Cl:CH2 and CH3C37Cl:CH2 have been observed in the ground and first excited torsional states. The ground-state rotational constants of CH3C35Cl:CH2 are A=9272.79±0.10 Mc/sec, B=4983.84±0.10 Mc/sec, and C=3304.39±0.10 Mc/sec. The ground-state rotational constants for CH3C37Cl:CH2 are A=9272.31±0.10 Mc/sec, B=4850.48±0.10 Mc/sec, and C=3245.11±0.10 Mc/sec. The quadrupole coupling constants along the appropriate principal inertial axes in the ground torsional state of CH3C35Cl:CH2 are χaa=−68.15±0.10 Mc/sec, χbb=37.11±0.10 Mc/sec, and χcc=31.04±0.10 Mc/sec. The quadrupole coupling constants for CH3C35Cl:CH2 in the excited torsional state were within the experimental error of the corresponding ground-state values. The quadrupole coupling constants in CH3C37Cl:CH2 are χaa=−53.80±0.10 Mc/sec, χbb=29.30±0.10 Mc/sec, and χcc=24.50±0.10 Mc/sec. Analysis of the first excited-torsional-state rotational spectrum yielded a barrier to the internal rotation of the methyl group of 2671±20 cal/mole. Microwave double-resonance experiments were used to provide a positive confirmation for the assignments of the 000→101 and 101→202 transitions in CH3C35Cl:CH2 as well as exhibiting some interesting features in the energy levels involved in the transitions. Two types of experiments were performed. The first experiments involved irradiating the quadrupole components in the 000→101 transition while observing the 101→202 transition. The second set of experiments involved irradiating one of the quadrupole components in the 000→101 transition and using a second klystron to observe the entire 000→101 triplet.