Atm. Marcelis et al., THERMAL AND OPTICAL-PROPERTIES OF CHIRAL TWIN LIQUID-CRYSTALLINE BIS(CHOLESTERYL) ALKANEDIOATES, Journal of materials chemistry, 6(9), 1996, pp. 1469-1472
The thermal and optical properties of a series of bis (cholesteryl) al
kanedioates were investigated. The melting points, the cholesteric to
isotropic transition temperatures, the entropy changes at this tempera
ture and the selective reflection wavelengths of the cholesteric phase
all exhibit an odd-even effect as a function of spacer length. This i
s attributed to a difference in the ordering of the cholesteric phase
as a function of the parity of the spacer. Because the properties of t
he members of the series with a short spacer could not be measured for
several reasons, their properties were also determined as a 5 wt% sol
ution in a cholesteric host. A similar odd-even influence on the chole
steric to isotropic transition temperatures and the optical properties
of the host was observed as for the pure compounds. The influence on
the properties of the host is stronger for compounds with a short spac
er than for compounds with a longer spacer.