| 摘要 |
<p> (i) A compound of the formula:
<CHEM>
wherein R is H, a metal or a group containing a tetravalent N atom;
<CHEM>
R<1> is NO2, CN or COOY;
Y is H, C1-4-alkyl, a metal or a group containing a tetravalent N atom;
R<2> & R<3> are each independently H or a non-hydrophilic aliphatic or cycloaliphatic group containing up to 30 carbon atoms;
R<4> & R<5> are each independently H or a non-hydrophilic aliphatic or cycloaliphatic group containing up to 30 carbon atoms;
and R<6> & R<7> are each independently H or a non-hydrophilic group containing up to 4 carbon atoms;
or R<4> & R<6> together comprise ring fused to Ring A and R<5> & R<7> are as hereinbefore defined;
or R<5> & R<7> together comprise ring fused to Ring A and R<4> & R<6> are as hereinbefore defined;
or R<2> & R<4> together with the N atom to which R<2> is attached form a ring fused to Ring A and R<3> & R<5> are as hereinbefore defined;
or R<3> & R<5> together with the N atom to which R<3> is attached form a ring fused to Ring A and R<2> & R<4> are as hereinbefore defined;
provided there are, in total, from 8 to 40 carbon atoms in one or two of the groups independently represented by R<2>, R<3>, R<4> & R<5>;
(ii) an optical element comprising a compound of Formula I having non-linear optical (NLO) properties for use in the generation of NLO signals,
(iii) a method of preparation of such an optical element comprising a plurality of monomolecular layers of the compound of Formula I on the surface of a transparent or reflecting substrate by a Langmuir-Blodgett technique; and
(iv) an optical device incorporating such an optical element.</p> |
