Key Word : terthiophene-briged silsesquioxane, tergothiophene, lamellar, and birefringenceMaterials ceramics products based on SiO 2 gels have been produced via sol-gels processing in present of 1% NH 4 F/H 2 O as catalyst. Alkoxysilane from tetraethoxysilane (TEOS) are chose as a matrices or template sources, than the product's of syntheses precursor: 2,5-bis(trimethoxysilyl)terthiophene (= BTS3T) used as a motif organic compound. That product formed matrices as silicate backbone of terthiophene-briged silsesquioxane net-work; [O 1.5 Si-(C 4 H 2 S) n -SiO 1.5 ] n . The structure silsesquioxane terthiophene-briged formed have layer distance of 4.6and 8.6 angstroms. So, that terthiophenes units in their structure give an effect on the characteristic pattern as an ordered micro lamellar structure. Electron microscopy analyses in matrices -Si-O-Sithere spheres formed by diameter about 10 µm which are rich in silicon.The effect of terthiophenes unites on SiO 2 gels formed shown that birefringence phenomenas are strong in presence of higher quantity oligothiophenes units, and will decrease with increase quantity of alkoxysilane, with anisotropic values differences decrease every 1.125 x 10 -3 per mole SiO 2 , whereas the optical transparency of SiO 2 gels formed are increase.
INTRODUCTIONPreparation of ceramics via sol-gel processing from alkoxysilane containing motif organic precursor is very widely used for development of new materials with certain characteristic of optical applications. The alkoxysilane functions were partially hydrolyzed and condensed as the matrix formation [1].The alkoxysilane are usually used are tetramethoxysilane Si(OMe) 4 , more usually know as TMOS and tetraethoxysilane, Si(OEt) 4 , known as TEOS. Both compounds have become a notorious chemical precursor in two important and widely used applications: (a) the preparation of inorganic materials by sol-gel methods [1], and (b) the formation of