alpha,omega -Diphenylpermethyloligosilanes, Ph(SiMe2)(n)Ph where n = 12 (3), and 13 (4), showed the mesophases in the range of 126-139 and 127-155 degreesC, respectively. In the mesophases, the silicon chains adopted the all-trans conformation and were perpendicular to the layer plane and hexagonally ordered within the layer, Furthermore, the phenyls at both ends of the silicon chain were interdigitated between the neighboring layers.