Ordering of apolar and polar solutes in nematic solvents

Autor: Andreas F. Terzis, Christoph Wutz, Edward T. Samulski, Demetri J. Photinos, T. Dingemans
Rok vydání: 2003
Předmět:
Zdroj: The Journal of Chemical Physics. 118:7046-7061
ISSN: 1089-7690
0021-9606
DOI: 10.1063/1.1560941
Popis: The quadrupolar splittings of deuteriated para- and ortho-dichlorobenzene (1,4-DCB and 1,2-DCB, respectively) are measured by nuclear magnetic resonance (NMR) in the nematic solvents hexyl- and pentyloxy-substituted diphenyl diacetylene (DPDA-C6 and DPDA-OC5, respectively). Measurements are taken for all four combinations of the nominally apolar (1,4-DCB) and polar (1,2-DCB) solutes in the apolar (DPDA-C6) and polar (DPDA-OC5) solvents, and throughout the entire nematic temperature range of the solutions. The temperature dependence of the second-rank orientational order parameters of the solutes are obtained from these measurements and the respective order parameters of the mesogenic cores of solvent molecules are obtained independently from carbon-13 NMR measurements. The order parameter profiles of the two solutes are found to be very different but show little variation from one solvent to the other. The results are analyzed and interpreted in terms of the underlying molecular interactions using atomist...
Databáze: OpenAIRE