The r -structure of thiophene in various liquid crystals with 13C-methane as an internal reference

Abstract
The r -structure of thiophene was studied in thermotropic liquid crystals and in their mixtures. In each case, 13C-enriched methane was added to the sample to serve as an internal ‘deformation reference’. The results indicate that the structure of thiophene is very sensitive to the liquid crystal environment. The structure obtained for thiophene in such liquid crystal mixtures in which the D CH of methane is vanishingly small is in agreement with the microwave structure. The best agreement, however, is obtained in the mixture of MBBA and ZLI 1167 where the D CH of methane is c. 2 Hz.