  The n-alkanes C12H26, C14H30, and C16H34 have been imbibed and solidified in
mesoporous Vycor glass with a mean pore diameter of 10nm. The samples have been
investigated by x-ray diffractometry and calorimetric measurements. The
structures and phase sequences have been determined. Apart from a reduction and
the hysteresis of the melting/freezing transition, pore confined C12 reproduces
the liquid-triclinic phase sequence of the bulk material, but for C16 an
orthorhombic rotator mesophase appears that in the bulk state is absent for C16
but well known from odd numbered alkanes of similar length. In pore confined
C14 this phase shows up on cooling but not on heating.
