NUCLEAR MAGNETIC-RELAXATION AND MOLECULAR-REORIENTATION OF DICYANOACETYLENE IN HYDROCARBON SOLUTIONS

14N linewidths and 13C spin lattice relaxation rates have been measured for dicyanoacetylene, neat and in several hydrocarbon solutions. The correlation between molecular reorientation rates and solvent viscosity is found to break down in the sense that the reorientation rates of dicyanoacetylene in aromatic solvents are significantly slower than in saturated hydrocarbon solvents. Without making reference to specific solute-solvent interactions this behavior may be rationalized by taking into account the isothermal compressibility of the various solvents. © 1979 American Institute of Physics.