Calcined MCM-41 type mesoporous samples have been characterized by tra
nsmission electron microscopy(TEM). Samples are not crystalline at the
atomic level. The existence of an array of long silicate tubules pack
ed in honeycomb fashion, nearly always bent and curved has been eviden
ced. The formation of such a silicate architecture through a liquid-cr
ystal template mechanism had been hypothesized before. Equidistant par
allel lines observed in this study are shown to be related to the hexa
gonal repeat between tubules: the honeycomb array is sufficiently regu
lar to give fringes in projection under proper orientation of the spec
imen. The existence of a hypothetical lamellar phase in the calcined m
aterial is not confirmed by our observations. Samples with different c
ompositions all had the same general architecture.