Preferred Label : liquid-crystal transitions;
IUPAC definition : A liquid crystal is a molecular crystal with properties that are both solid- and liquid-like.
Liquid crystals are composed predominantly of rod-like or disc-like molecules, that
can exhibit one or more different, ordered fluid phases as well as the isotropic fluid;
the translational order is wholly or partially destroyed but a considerable degree
of orientational order is retained on passing from the crystalline to the liquid phase
in a mesomorphic transition. ol li Transition to a nematic phase. br/ A mesomorphic
transition that occurs when a molecular crystal is heated to form a nematic phase
in which the mean direction of the molecules is parallel or antiparallel to an axis
known as the director. /li li Transition to a cholesteric phase. br/ A mesomorphic
transition that occurs when a molecular crystal is heated to form a cholesteric phase
in which there is simply a spiralling of the local orientational order perpendicular
to the long axes of the molecules. /li li Transition to a smectic state. br/ A
mesomorphic transition that occurs when a molecular crystal is heated to yield a smectic
state in which there is a one-dimensional density wave which produces very soft/disordered
layers. /li /ol ;
Origin ID : L03579;
See also
A liquid crystal is a molecular crystal with properties that are both solid- and liquid-like.
Liquid crystals are composed predominantly of rod-like or disc-like molecules, that
can exhibit one or more different, ordered fluid phases as well as the isotropic fluid;
the translational order is wholly or partially destroyed but a considerable degree
of orientational order is retained on passing from the crystalline to the liquid phase
in a mesomorphic transition. ol li Transition to a nematic phase. br/ A mesomorphic
transition that occurs when a molecular crystal is heated to form a nematic phase
in which the mean direction of the molecules is parallel or antiparallel to an axis
known as the director. /li li Transition to a cholesteric phase. br/ A mesomorphic
transition that occurs when a molecular crystal is heated to form a cholesteric phase
in which there is simply a spiralling of the local orientational order perpendicular
to the long axes of the molecules. /li li Transition to a smectic state. br/ A
mesomorphic transition that occurs when a molecular crystal is heated to yield a smectic
state in which there is a one-dimensional density wave which produces very soft/disordered
layers. /li /ol
