Optically non-linear materials and thin films incorporating these materials

Claim 1

A body of optically non-linear material, comprising a multilayer Langmuir-Blodgett film having molecules extending perpendicular to the plane of the film in a Y configuration, alternate monolayers of said film being composed of first elongate chromophore molecules each having an electron donor-acceptor (D/A) pair and being of the general formula: ##STR10## and second elongate chromophore molecules each having an electron donor/acceptor pair and being of the general formula: ##STR11## wherein D and D' are the same or different electron-donor atoms or groups, Ch and Ch' are the same or different elongate chromophore groups, A and A' are the same or different electron-acceptor atoms or groups, and Hy and Hy' are the same or different hydrophobic groups, whereby the electron donor/acceptor pairs of alternate layers are reversed relative to the respective hydrophobic group so that all of said electron donor-aceptor pairs of said molecules have the same orientation throughout the thickness direction of said Y-configuration film.

Claim 24

A method of making a body of optically non-linear material comprising the steps: (a) depositing alternate layers of compounds of the general formulae: ##STR16## in a Langmuir Blodgett film, R 3 and R 4 being independently H or the same or different alkyls such that the groups ##STR17## are hydrophilic groups, C j and C j ' being the same or different substituted conjugated hydrocarbon and/or aromatic groups, D being an electron-donor atom or group, A being an electron-acceptor atom or group, D and/or A being attached to a hydrophilic group, such that said compounds are oriented substantially in the Y-configuration; and (b) exposing said film to hydrazine so as to form conjugated links between said layers which can transmit charge from D to A, whereby the overall configuration of the resultant multilayer film is non-centrosymmetric.

Claim 25

A method of making a body of optically non-linear material comprising the steps: (a) depositing alternate layers of compounds of the general formulae: ##STR16## in a Langmuir Blodgett film, R 3 and R 4 being independently H or the same or different alkyls such that the groups ##STR17## are hydrophilic groups, C j and C j ' being the same or different substituted conjugated hydrocarbon and/or aromatic groups, D being an electron-donor atom or group, A being an electron-acceptor atom or group, D and/or A being attached to a hydrophilic group, such that said compounds are oriented substantially in the Y-configuration; and (b) exposing said film to hydrazine so as to form conjugated links between said layers which can transmit charge from D to A, whereby the overall configuration of the resultant multilayer film is non-centrosymmetric.