Materials of formula (I): [G]g(SiO1/2)x are described where G is R3SiR1R2(O)k; R1, R2, R3 are independently a C1-16 alkyl which may be partly or fully halogenated, H and formula (IA), wherein Y is selected from COO, OCO, O, S, CHOH, CHF, CH2; Q=(CH2)n where one or more non-adjacent methylenes may be replaced by O and n=1=20; Z is O, S, a single covalent bond, COO, OCO; when Y is CH2, then n may also be 0; (a) represents any mesogenic group; provided that at least one of R1, R2, R3, is selected from formula (IA): k=0 or 1; g=4 or 6 or 8 or 10 or 12; 1=3 or 8 provided that: if k=1, 1=3 and x is selected form 6, 8, 10, 12 then g=x; if k=0, 1=8 and g=4 then x=1; and further provided that G may have up to g different structures for any single compound. Pyroelectric and piezoelectric devices, liquid crystal electro-optical display devices and optical recording media containing the adsorbed liquid crystals mixed with other liquid crystal materials are described.