Lyotropic compositions containing nonlinear optical chromophores

Abstract

To provide nonlinear optical chromophores which form lyotropic mixtures in a solvent and exhibit liquid crystalline properties, providing improved poling efficiency.SOLUTION: A lyotropic composition comprises a nonlinear optical chromophore represented by the general formula (I): D-Π-A. In the formula: D represents an organic electron-donating group; A represents an organic electron-accepting group having an electron affinity greater than the electron affinity of D; and Π represents a Π-bridge between A and D; where the electron-donating group D comprises a tetrahydrocarbazole moiety bound to the Π-bridge at a carbon atom in the tetrahydro six-membered carbon ring of the tetrahydrocarbazole moiety, and where the hydrogen bound to the nitrogen of the five-membered ring of the carbazole moiety is replaced with a substituent R, where R represents a moiety other than hydrogen.SELECTED DRAWING: None

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 288,089, filed December 10, 2021, the entire contents of which are incorporated herein by reference. [Background technology]

[0002] Nonlinear optical (NLO) chromophores provide the electro-optical (EO) activity in poled polymer electro-optic devices. Electro-optic polymers have long been investigated as an alternative to inorganic materials such as lithium niobate in electro-optic devices. Electro-optic devices can include external modulators for applications such as telecommunications, datacom, RF photonics, and optical interconnects. Polymeric electro-optic materials have shown great potential for core applications in a wide range of next-generation systems and devices, including electro-optical modulators, optical switches, phased array radar, satellite and fiber optic communications, cable television (CATV), optical gyroscopes for aviation and missile guidance, electronic countermeasures (ECM) systems, backplane interconnects for high-speed computing, ultrafast analog-to-digital conversion, mine detection, radio frequency photonics, spatial light modulation, and all-optical (optical-switching-optical) signal processing.

[0003] Many NLO molecules (chromophores) have been synthesized with high molecular electro-optic properties. The product of molecular dipole moment (μ) and hyperpolarizability (β) is often used as a measure of a molecule's electro-optic performance due to the dipole's involvement in material processing. See U.S. Patent No. 5,849,333, entitled "New Class of High Hyperpolarizability Organic Chromophores and Process for Synthesizing the Same," by Dalton et al.

[0004] Nevertheless, it is possible to calculate the hyperpolarizability of a microscopic molecule (β) by comparing it to the hyperpolarizability of a macroscopic material (χ 2) has been extremely challenging to translate into practical applications. This is because the molecular auxiliary components (chromophores) must be incorporated into NLO materials that exhibit (i) high macroscopic nonlinearity and (ii) sufficient temporal, thermal, chemical, and photochemical stability. High electro-optic activity and the stability of the electro-optic activity, also known as "temporal stability," are important for commercially viable devices. The electro-optic activity of electro-optic polymers can be increased by increasing the concentration of the nonlinear optical chromophore in the host polymer and enhancing the electro-optic properties of the chromophore. However, some techniques for increasing the chromophore concentration can decrease the temporal stability. Simultaneously solving these dual problems is considered a final obstacle to the widespread commercialization of EO polymers in numerous devices and systems.

[0005] NLO chromophores have poor aggregation properties, making them ideal for high hyperpolarizability materials (χ 2 The fabrication of NLO chromophores is limited. Commercially usable materials must contain a large molecular density of chromophores with the desired molecular moments statistically oriented around a single material axis. To achieve this, the charge-transfer (dipole) nature of NLO chromophores is typically exploited during material processing by applying an external electric field, which localizes low-energy states favoring non-centrosymmetric dimensions. Unfortunately, even at moderate chromophore densities, the molecules form multimolecular dipolar-bonded (centrosymmetric) aggregates that cannot be removed via practical electric field energy. To overcome this problem, non-aggregating dipolar chromophores are typically incorporated into cooperative material structures by constructing physical barriers (e.g., antipacking steric groups) that restrict the association between neighboring molecules.

[0006] Therefore, a high glass transition temperature (T gIt is widely believed that producing nonlinear optical chromophores, including materials that exhibit high glass transition temperatures, would be beneficial in the art. Materials with high glass transition temperatures exhibit improved thermal stability and maintain their macroscopic electro-optical properties to a greater extent than materials with low glass transition temperatures. However, materials with such elevated glass transition temperatures require very high temperatures during the poling process to achieve sufficient alignment. However, the need to achieve such high temperatures is costly and time-consuming, resulting in inefficient poling. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. 2000 / 09613 [Patent Document 2] U.S. Patent Application No. 63 / 264,880 [Patent Document 3] U.S. Patent Publication No. 2012 / 0267583A1 [Patent Document 4] U.S. Patent Publication No. 2012 / 0267583A1 [Patent Document 5] U.S. Patent No. 5,670,091 [Patent Document 6] U.S. Patent No. 5,679,763 [Patent Document 7] U.S. Patent No. 6,090,332 [Patent Document 8] U.S. Patent No. 6,716,995 [Patent Document 9] U.S. Patent Application No. 17 / 358,960 [Patent Document 10] U.S. Patent Publication No. 2007 / 0260062 [Patent Document 11] U.S. Patent Publication No. 2007 / 0260063 [Patent Document 12] U.S. Patent Publication No. 2008 / 0009620 [Patent Document 13] U.S. Patent Publication No. 2008 / 0139812 [Patent Document 14] U.S. Patent Publication No. 2009 / 0005561 [Patent Document 15] U.S. Patent Publication No. 2012 / 0267583A1 [Patent Document 16] U.S. Patent No. 6,584,266 [Patent Document 17] U.S. Patent No. 6,393,190 [Patent Document 18] U.S. Patent No. 6,448,416 [Patent Document 19] U.S. Patent No. 6,44,830 [Patent Document 20] U.S. Patent No. 6,514,434 [Patent Document 21] U.S. Patent No. 5,044,725 [Patent Document 22] U.S. Patent No. 4,795,664 [Patent Document 23] U.S. Patent No. 5,247,042 [Patent Document 24] U.S. Patent No. 5,196,509 [Patent Document 25] U.S. Patent No. 4,810,338 [Patent Document 26] U.S. Patent No. 4,936,645 [Patent Document 27] U.S. Patent No. 4,767,169 [Patent Document 28] U.S. Patent No. 5,326,661 [Patent Document 29] U.S. Patent No. 5,187,234 [Patent Document 30] U.S. Patent No. 5,170,461 [Patent Document 31] U.S. Patent No. 5,133,037 [Patent Document 32] U.S. Patent No. 5,106,211 [Patent Document 33] U.S. Patent No. 5,006,285 [Patent Document 34] U.S. Patent Application No. 17 / 358,960 [Patent Document 35] U.S. Patent No. 6,584,266 [Patent Document 36] [[ID=十七]]U.S. Patent No. 6,393,190 [Patent Document 37] U.S. Patent No. 6,448,416 [Patent Document 38] U.S. Patent No. 6,44,830 [Patent Document 39] U.S. Patent No. 6,514,434 [Patent Document 40] U.S. Patent Application No. 17 / 358,960 [Non-Patent Document]

[0008] [Non-Patent Document 1] Chia-Chi Teng, Measuring Electro-Optic Constants of a Poled Film, in Nonlinear Optics of Organic Molecules and Polymers, Chp. 7, 447-49 (Hari Singh Nalwa & Seizo Miyata eds., 1997) [Non-Patent Document 2] C. W. Thiel, "For- wave Mixing and Its Applications,"www.physics.montana.edu.students.thiel.docs / FWMixing.pdf, [Summary of the Invention]

[0009] [[ID=5十三]] The present invention relates generally to nonlinear optical chromophores that form lyotropic mixtures in solvents and exhibit liquid crystalline properties. Thus, various embodiments of the present invention can provide improved poling efficiency.

[0010] Various embodiments of the present invention exhibit liquid crystalline properties and, when mixed with a solvent, form lyotropic compositions. For example, in certain embodiments, the chromophore exhibits a lyotropic nematic liquid crystalline phase in a polar organic solvent. The resulting liquid crystalline properties provide a mechanical anisotropy effect that allows the formation of a non-centrosymmetric chromophore-polymer matrix without the application of an electric field. In accordance with various embodiments described herein, the chromophore exhibits a sufficient electro-optic coefficient (r 33 ) is mechanically induced, and the need for applying poling temperatures and electric fields, typically 170°C and 100 v / pm, can be reduced. The liquid crystal properties and lyotropic composition allow for mild processing conditions and therefore high poling efficiency.

[0011] Various embodiments of the present invention comprise a nonlinear optical chromophore represented by general formula (I): D-Π-A (I) wherein D represents an organic electron donor group, A represents an organic electron withdrawing group having an electron affinity greater than that of D, and Π represents a Π bridge between A and D; The organic electron donor group D comprises a tetrahydrocarbazole moiety connected with a π-bridge at a carbon atom in the tetrahydro six-membered carbon ring of the tetrahydrocarbazole moiety, and the hydrogen attached to the nitrogen of the tetrahydro five-membered ring of the carbazole moiety is replaced with a substituent R.

[0012] Various embodiments of the present invention include lyotropic compositions comprising a nonlinear optical chromophore represented by general formula (I) and a solvent.

[0013] Various embodiments of the present invention include thin films formed from compositions as described herein. Various embodiments of the present invention include electro-optical devices comprising thin films as described herein.

[0014] Other aspects, features, and advantages will become apparent from the following disclosure, including the detailed description, preferred embodiments, and the appended claims.

[0015] The foregoing summary, as well as the following detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the accompanying drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments that are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. [Brief description of the drawing]

[0016]

[0014] FIG. 1 is a representative diagram of the optical absorption of a chromophore according to an embodiment of the present invention in the lyotropic phase and after solvent removal. [FIG. 2a] FIG. 2a is a polarized light microscope image of a chromophore according to an embodiment of the present invention forming a micelle in a solvent. [FIG. 2b] FIG. 2b is a polarized microscope image of a chromophore according to an embodiment of the present invention after shear alignment exhibiting a red shift. [FIG. 2c] FIG. 2c is a polarized light microscope image of a chromophore according to an embodiment of the present invention after removal of the solvent. DETAILED DESCRIPTION OF THE INVENTION

[0017] [Detailed Description of the Invention] As used herein, the singular terms "a" and "the" are synonymous and are used interchangeably with "one or more" and "at least one," unless otherwise indicated by language and / or context. Thus, for example, the phrase "solvent" or "said solvent" herein or in the appended claims can refer to a single solvent or more than one solvent or a mixture thereof. As a further example, and not limited to only multiple electron donor groups, the phrase "electron donor group" or "said electron donor group" herein or in the appended claims can refer to a single electron donor group or more than one electron donor group (e.g., "D" in any molecular formula herein can represent two or more electron donor groups, both of which may be attached to a π bridge). Furthermore, unless otherwise specified, all numerical values ​​are understood to be modified by the word "about."

[0018] As used herein, the term "nonlinear optical chromophore" (NLOC) refers to a molecule or portion of a molecule that produces a nonlinear optical effect when illuminated with light. A chromophore is any molecular unit that produces a nonlinear optical effect upon interaction with light. The desired effect can occur at a resonant or nonresonant wavelength. The activity of a particular chromophore in a nonlinear optical material is expressed as its hyperpolarizability, which is directly related to the molecular dipole moment of the chromophore. Various embodiments of the NLO chromophores of the present invention are structures useful for producing NLO effects.

[0019] Nonlinear optical chromophores according to various embodiments of the present invention exhibit liquid crystal properties and form lyotropic compositions when mixed with a solvent. Nonlinear optical chromophores according to various embodiments of the present invention exhibit high glass transition temperatures and, when mixed with a solvent to form a lyotropic composition, exhibit self-aligned J-aggregates, as opposed to the head-to-tail alignment exhibited by the prior art (i.e., H-aggregates). Nonlinear optical chromophores according to various embodiments of the present invention are combined with a solvent neat (i.e., without the addition of a matrix material or host polymer) to form a lyotropic composition, followed by additional shear to at least partially self-align the nonlinear optical chromophores and form a highly ordered and highly packed state. In various embodiments of the present invention, no further poling is required to provide nonlinear optical thin films for use in electro-optical devices, such as modulators. In various embodiments of the present invention, the solvent can be removed under controlled conditions to maintain the chromophores in a highly ordered and highly packed state. In various embodiments of the present invention, conventional poling processes can also be implemented, including applications in the art of thin chromophore films. Nonlinear optical chromophores according to various embodiments of the present invention can be combined with a matrix material or host polymer and a solvent to form a lyotropic composition. In various embodiments of the present invention, high-boiling point solvents can be used for poling according to the methods described in U.S. Patent Application Publication No. 2020 / 0122999, filed December 3, 2021, the entire contents of which are incorporated herein by reference.

[0020] First-order hyperpolarizability (β) is one of the most common and useful NLO properties. Higher-order hyperpolarizabilities are useful in other applications, such as any optical (light-switching-light) application. By carrying out the following tests, it is possible to determine whether a compound or material, such as a polymer, has first-order hyperpolarizability properties and a sufficient electro-optic coefficient (r 33It can be determined whether a material contains a nonlinear optical chromophore with a β function (β). First, the material in thin film form is placed in an electric field to align the dipoles. This can be done, for example, by sandwiching a film of the material between electrodes such as an indium tin oxide (ITO) substrate, a gold film, or a silver film.

[0021] The material is measured at its glass transition temperature (T g A potential is applied to the electrodes while heating the film near the electrode, generating a poling field. After a suitable time, the temperature is gradually decreased while maintaining the poling field. Alternatively, the material can be polarized by corona poling, in which a poling field is provided by a charged needle placed a suitable distance from the material film. In either case, dipoles in the material tend to align with the electric field.

[0022] The nonlinear optical properties of a poled material are tested as follows: polarized light, often from a laser, is passed through the poled material and then through a polarizing filter and a light intensity detector. If the intensity of the light received by the detector changes when the potential applied to the electrodes is changed, then the material contains a nonlinear optical chromophore and has an electro-optically variable refractive index. Techniques for measuring the electro-optic constants of poled films containing nonlinear optical chromophores are discussed in detail in "Electro-optical Properties of Polarized Films Containing Nonlinear Optical Chromophores," IEEE Transactions on Applied Physics, Vol. 1, No. 1, pp. 111-114, 2002, which is incorporated herein by reference in its entirety, except that in the event of any disclosure or definition that conflicts with this application, the disclosure or definition herein shall be deemed to control.

[0023] The relationship between the change in applied potential and the change in refractive index of a material is its EO coefficient, r 33 This effect is commonly referred to as the electro-optic effect, or EO effect. A device containing a material whose refractive index changes in response to a change in applied electric potential is called an electro-optic (EO) device.

[0024] Second-order hyperpolarizability (γ) or third-order susceptibility (χ (3)) is a typical measure of third-order NLO activity. There are several ways to measure these properties, but degenerate four-wave mixing (DFWM) is very common. See "Degenerate Four-Wave Mixing" by Chris G. "Degenerate Four-Wave Mixing" (DFT), "Analysis of Third-Order NLO Activity," IEEE Transactions on Optical Engineering, Vol. 1, No. 1, pp. 111-114, 2002, the entire contents of which are incorporated herein by reference. See "Patent Document 3," pp. 111-114, 2002, the entire contents of which are incorporated herein by reference. A method known in the art as degenerate four-wave mixing (DFWM) can be used to characterize the third-order NLO properties of thin films. In Figure 4 of Patent Document 4, beams 1 and 2 are picosecond coherent pulses absorbed by an NLO film deposited on a glass substrate. Beam 3 is a weaker beam with the same wavelength as beams 1 and 2, but slightly delayed. Beam 4 is generated by wave mixing diffracted from a temporal holographic grating, which is generated by the interference of beams 1 and 2 within the material of the NLO film. Beam 3 can be a "control" beam at a telecommunications wavelength that generates a "signal" beam at a frequency not absorbed by the NLO material.

[0025] The nonlinear optical chromophores according to various embodiments of the present invention have the general formula (I): D-Π-A (I) wherein D represents an organic electron donor group, A represents an organic electron withdrawing group having an electron affinity greater than that of D, and Π represents a Π bridge between A and D. The terms electron donor group (donor or "D"), Π bridge (bridging group or Π), and electron withdrawing group (acceptor or "A"), as well as general synthetic methods for forming D-Π-A chromophores, are known in the art and are described, for example, in U.S. Patent Nos. 5,629,999, 5,629,999, 5,629,999, 5,629,999, and 5,629,999, filed June 25, 2021, the contents of which are incorporated herein by reference in their entireties.

[0026] The acceptor is an atom or group of atoms with a low reduction potential that can accept electrons from the donor via a π-bridge. The acceptor (A) has a higher electron affinity than the donor (D), so that, at least in the absence of an external electric field, the chromophore is generally polarized with a relatively high electron density on the acceptor (D) in the ground state. Typically, the acceptor group contains at least one electronegative heteroatom that is part of a pi bond (double or triple bond), so that a resonance structure can be derived in which the heteroatom acquires a formal negative charge by transferring an electron pair from the pi bond to the heteroatom and simultaneously reducing the multiplicity of the pi bond (i.e., converting a double bond to a formal single bond or a triple bond to a formal double bond). This heteroatom can be part of a heterocycle. Exemplary acceptor groups include, but are not limited to, -NO, -CN, -CHO, COR, COR, -PO(OR), -SOR, -SOR, and -SOR (where R is alkyl, aryl, or heteroaryl). The total number of heteroatoms and carbons in the acceptor group is about 30, and the acceptor group may be further substituted with alkyl, aryl, and / or heteroaryl.

[0027] Suitable electron-withdrawing groups "A" (also referred to in the literature as electron-withdrawing groups) for the nonlinear optical chromophores according to various embodiments of the present invention include those described in U.S. Patent Nos. 5,629,999, ...

[0028] In the various nonlinear optical chromophores according to various preferred embodiments of the present invention, suitable electron-withdrawing groups are represented by the general formula (I a ),

[0029] [ka]

[0030] In the formula, R 2 and R 3 are each independently H, substituted or unsubstituted C-C 10 alkyl, substituted or unsubstituted C2-C 10 Alkenyl, substituted or unsubstituted C2-C 10 Alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted carbocycle, substituted or unsubstituted heterocycle, substituted or unsubstituted cyclohexyl, and (CH) n -O-(CH2) n (n is 1 to 10). As used herein,

[0031] [ka]

[0032] represents a point of attachment to another part of a larger molecular structure. In various preferred embodiments, R 2 and R 3 One or both of R represent halogen-substituted moieties. Halogen substitution can refer to mono-, di-, tri-, and higher degrees of substitution. In various preferred embodiments, R 2 and R 3 One of R represents a halogen-substituted alkyl moiety and the other represents an aromatic moiety. 2 and R 3 One of the groups represents a halogen-substituted aromatic moiety and the other represents an alkyl moiety. In various preferred embodiments, the electron-withdrawing group may be represented by the following formula:

[0033] [ka]

[0034] In various preferred embodiments, the electron-withdrawing group can be represented by the following formula:

[0035] [ka]

[0036] In various preferred embodiments, the electron-withdrawing group can be represented by the following formula:

[0037] [ka]

[0038] The donor comprises an atom or group of atoms with a low oxidation potential, which can donate electrons to an acceptor "A" via a π-bridge. The donor (D) has a lower electron affinity than the acceptor (A), so that, at least in the absence of an external electric field, the chromophore is generally polarized with a relatively low electron density on the donor (D).

[0039] The donor according to various preferred embodiments of the present invention may comprise a tetrahydrocarbazole moiety, represented by general formula (II).

[0040] [ka]

[0041] In the formula, R 1 represents a moiety other than hydrogen, and R 2 represents a moiety selected from hydrogen, halide, alkoxy group, alkyl group (branched or unbranched), and aryl group; R 3 represents a moiety selected from hydrogen and alkyl groups (branched or unbranched), and R 4represents a moiety selected from hydrogen and alkyl groups (branched or unbranched), and R 5 may optionally represent a fused aliphatic or aromatic ring having 3 to 5 carbon atoms. 3 and R 4 , may represent the same moiety. In various embodiments, R 1 represents a moiety selected from the group consisting of branched alkyl groups and aryl groups. 1 represents a moiety selected from substituted or unsubstituted benzyl groups.

[0042] Donors according to various embodiments of the present invention may include a tetrahydrocarbazole moiety, represented by general formula (IIa).

[0043] [ka]

[0044] In the formula, R represents a moiety other than hydrogen.

[0045] In various embodiments, the donor comprises a tetrahydrocarbazole moiety represented by general formula (II), R 1 may represent an aryl-containing moiety. In various embodiments, R 1 may represent an aryl group further substituted with a silyl group. In various embodiments, R 1 may represent an aryl group further substituted with a triaryl-substituted silyl group. 1 may represent 4-(triphenylsilyl)-phenylmethyl.

[0046] In various embodiments, the donor comprises a tetrahydrocarbazole moiety represented by general formula (IIa), where R can represent an aryl-containing moiety. In various embodiments, R can represent an aryl group further substituted with a silyl group. In various embodiments, R can represent an aryl group further substituted with a triaryl-substituted silyl group. In various embodiments, R can represent 4-(triphenylsilyl)-phenylmethyl.

[0047] A "π bridge" includes an atom or group of atoms that can delocalize electrons from an electron donor (defined above) to an electron acceptor (defined above) through the orbitals of the atoms in the bridge. Such groups are very well known in the art. Typically, the orbitals are double (sp 2 ) or p orbitals on triple (sp) bonded carbon atoms. Additionally, the orbitals may be p orbitals on atoms such as boron or nitrogen. Additionally, the orbitals may be p, d, or f organometallic orbitals or hybrid organometallic orbitals. The atoms of the bridge containing the orbitals in which the electrons are delocalized are referred to herein as "critical atoms." The number of critical atoms in the bridge may range from 1 to about 30. The critical atoms may be substituted with organic or inorganic groups. The substituents may be selected to improve the solubility of the chromophore in the polymer matrix, to increase the stability of the chromophore, or for other purposes.

[0048] Suitable bridging groups (Π) of the nonlinear optical chromophores according to general formula (I) of the present invention include those described in U.S. Patent No. 5,629,299, ... and U.S. Patent No. 5,629,299, filed June 25, 2021, the entire contents of which are incorporated herein by reference.

[0049] In various preferred embodiments, the bridging group (Π) of the nonlinear optical chromophore according to general formula (I) of the present invention is represented by the general formula (II a ) bridging group.

[0050] [ka]

[0051] In the formula, X represents a substituted or unsubstituted, branched or unbranched C2-C4 diyl moiety, a and b each independently represent an integer of 0 to 3, and z represents an integer of 0 to 3. In various embodiments, the general formula (II a In various preferred embodiments, the bridging group (Π) of the nonlinear optical chromophore according to the general formula (I) of the present invention can be a group represented by the general formula (II b ) bridging group.

[0052] [ka]

[0053] X represents a substituted or unsubstituted, branched or unbranched C2-C4 diyl moiety. In various embodiments of the present invention, one or more diamondoid groups are represented by the general formula II a or II b By covalently bonding to a bridging group according to the formula (I), one or more diamondoid groups may be bonded, for example, to a sulfur atom or an oxygen atom of a thiophene group, or may be bonded to one or more carbon atoms of X via an ether or thioether bond.

[0054] In various preferred embodiments, the bridging group (Π) of the nonlinear optical chromophore according to general formula (I) of the present invention is represented by the general formula (II c ) bridging group.

[0055] [ka]

[0056] wherein each Y independently represents a diamondoid-containing group covalently bonded to a bridging group via any of the various bonds described herein below, including, but not limited to, ether and thioether bonds, or each Y can represent hydrogen, an alkyl group, an aryl group, a sulfur- or oxygen-linked alkyl or aryl group, or any branched or unbranched heteroatom-containing C1-C4 substituent; a and b independently represent an integer from 0 to 3; z independently represent an integer from 1 to 3; and each A arc independently represents a substituted or unsubstituted C2-C4 alkyl group, which together with the carbon bearing the Y substituent and its two adjacent carbon atoms form a cyclic group. The substituted or unsubstituted C2-C4 alkyl group comprising A arc contains 1 to 4 hydrogen substituents, each of which may be a substituted or unsubstituted C1-C4 alkyl group. 10 alkyl, substituted or unsubstituted C2-C 10 Alkenyl, substituted or unsubstituted C2-C 10 Alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted carbocycle, substituted or unsubstituted heterocycle, substituted or unsubstituted cyclohexyl, and (CH) n -O-(CH2) n (n is 1 to 10). In various preferred embodiments, z represents 1. In various embodiments according to the present invention, the electron donor or electron withdrawing group may comprise one or more covalently bonded diamondoid groups and may be represented by the general formula II c Y may represent any of the substituents described above. In certain preferred embodiments, the chromophore may include one or more covalently bonded electron donor groups, preferably including adamantyl, and the bridging group may be represented by general formula II, where Y represents an aryl thioether substituent. c It may contain an isophorone group according to the formula:

[0057] In various preferred embodiments, the bridging group (Π) of the nonlinear optical chromophore according to general formula (I) of the present invention is represented by the general formula (II d ) bridging group.

[0058] [ka]

[0059] wherein each Y independently represents a diamondoid-containing group covalently bonded to a bridging group via any of the various linkages described herein below, including, but not limited to, ether and thioether linkages, or each Y can represent hydrogen, an alkyl group, an aryl group, a sulfur- or oxygen-linked alkyl or aryl group, an aryl group (optionally bearing a diamondoid group) directly linked by a carbon-carbon bond (e.g., adamantyl anisole), a halogen, a halogenated alkyl group, a halogenated aryl group, or any branched or unbranched heteroatom-containing C1-C4 substituent, and a and b independently represent an integer from 0 to 3, and z represents an integer from 1 to 3. In various embodiments according to the present invention, the electron donor or electron-withdrawing group can comprise one or more covalently bonded diamondoid groups and can be represented by the general formula II d Y in the formula (II) may represent any of the substituents described above. In certain preferred embodiments, the chromophore may include one or more covalently bonded electron donor groups, preferably including adamantyl, and the bridging group may be represented by the formula (II) where Y represents an aryl thioether substituent. d In various embodiments, the isophorone group may be of the general formula II d The geminal methyl groups on the isophorone bridge of each of the methyl groups may be independently substituted or unsubstituted C1-C 10 alkyl, substituted or unsubstituted C2-C 10 Alkenyl, substituted or unsubstituted C2-C 10 Alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted carbocycle, substituted or unsubstituted heterocycle, substituted or unsubstituted cyclohexyl, halogen, halogenated alkyl groups (e.g., -CF), halogenated aryl and heteroaryl groups (e.g., pentafluorothiophenol), and (CH) n-O-(CH2) n (wherein n is 1 to 10).

[0060] For example, the bridging group (Π) of the nonlinear optical chromophore according to general formula (I) of the present invention can include:

[0061] [ka]

[0062] Specific examples of nonlinear optical chromophores according to various embodiments can include:

[0063] [ka]

[0064] [ka]

[0065] [ka]

[0066] [ka]

[0067] and

[0068] [ka]

[0069] Various embodiments of the present invention include lyotropic compositions comprising a nonlinear optical chromophore as described herein and a solvent. Suitable solvents for lyotropic compositions according to various embodiments of the present invention can include aprotic polar solvents and mixtures thereof. In various embodiments, a suitable solvent can include propylene carbonate.

[0070] Suitable solvents can be combined with the nonlinear optical chromophore in any amount. In various embodiments, one or more solvents can be combined with the nonlinear optical chromophore in an amount of about 25% to about 75% by weight, and in various embodiments, about 35% to about 65% by weight, and in various embodiments, about 40% to about 60% by weight. In various embodiments, one or more solvents can be combined with the nonlinear optical chromophore in an amount up to 50% by weight.

[0071] Lyotropic compositions of nonlinear optical chromophores and solvents according to various embodiments of the present invention exhibit at least partial self-alignment. Such compositions can be efficiently poled with minimal applied voltage. In various embodiments, lyotropic compositions exhibit a high degree of self-alignment under shear, such that no applied poling is required. Lyotropic compositions according to various embodiments of the present invention can form dense, highly packed, and highly ordered thin films for use in electro-optical devices. Thin films according to various embodiments of the present invention can be formed without or with an externally applied voltage. In various embodiments, thin films can be formed without an applied voltage.

[0072] The present invention will now be described in further detail with reference to the following non-limiting examples. [Example]

[0073] Synthesis example 1:

[0074] Step 1: Synthesis of triphenyl(p-tolyl)silane:

[0075] [ka]

[0076] A dry RB flask (1) was charged with 1-bromo-4-methyl-benzene (9.93 mL, 0.0807 mol) and THF (200 mL) and then cooled to −78° C. in a dry ice / acetone bath. n-Butyllithium (2.50 mol / L, 32.3 mL, 0.0807 mol) was added (in 5 mL increments) at a rate such that the temperature did not rise above −55° C., and the reaction was stirred under nitrogen at −78° C. for 2 hours.

[0077] Another RB flask (2) was evacuated and then filled with nitrogen three times, charged with triphenylsilyl chloride (26.2 g, 0.0888 mol), evacuated / filled with nitrogen three times, and stirred under vacuum at 60°C for 1 H. RB flask (2) was cooled and filled with nitrogen, then charged with THF (100 mL) and cooled to -78°C.

[0078] The contents of flask (2) were cannulated into flask (1) in a steady dropwise manner, causing the temperature to rise by 5° C. The reaction was stirred under nitrogen and allowed to warm slowly to room temperature.

[0079] The reaction was diluted with DCM, washed with water, then brine, dried over MgSO4, and evaporated to give a white solid, which was stirred in hexane for 1H and filtered / washed with hexane (500 mL).

[0080] Triphenyl(p-tolyl)silane (25.4 g, 0.0725 mol, yield: 89.8%) was obtained as a white powder.

[0081] Step 2: Wahl-Ziegler bromination reaction of triphenyl(p-tolyl)silane

[0082] [ka]

[0083] An RB flask was charged with triphenyl(p-tolyl)silane (0 mmol / L, 0 mL, 0.0394 mol), N-bromosuccinimide (7.36 g, 0.0413 mol), 400 mL of DCM, and 2-[(E)-(1-cyano-1-methyl-ethyl)azo]-2-methyl-propanenitrile (0.323 g, 0.00197 mol). The reaction was refluxed overnight under nitrogen. TLC showed quantitative conversion to the bromide.

[0084] The reaction mixture was washed with water, then brine, dried over MgSO4, and evaporated to a tan powder. This was triturated with hexane and filtered to give 3343-A, 13.8 g, and the filtrate was evaporated to give 3343-H, 3.49 g. The hexane fraction was chromatographed eluting with hexane / ethyl acetate (3-5%). The appropriate fractions were combined and evaporated to give 3343-Fraction-AB. Fraction B was triturated with hexane and filtered to give 3343-B as a very white granular powder, 885 mg.

[0085] 4-[(bromomethyl)phenyl]-triphenyl-silane (14.7 g, 0.0342 mol, yield: 87.0%) was obtained.

[0086] Step 3: Alkylation of 1,2,3,9-tetrahydrocarbazol-4-one

[0087] [ka]

[0088] An RB flask under nitrogen was charged with 4-[(bromomethyl)phenyl]-triphenyl-silane (13.8 g, 0.0321 mol), 1,2,3,9-tetrahydrocarbazol-4-one (5.95 g, 0.0321 mol), and 200 mL of DMF. The mixture was cooled to 0 °C, and then sodium hydride (60%, 1.41 g, 0.0353 mol) was added. The reaction was stirred under nitrogen and allowed to warm slowly to room temperature (RT). After 2 h of reaction, the mixture was allowed to warm and become homogenous. The product was allowed to stand for 15 min, and then stirring was stopped. The reaction mixture became a solid white paste.

[0089] The reaction was triturated in water, then filtered and washed with water. The organics were chromatographed, eluting with hexane / ethyl acetate (5%). The appropriate fractions were combined and evaporated to give an off-white solid, which was dissolved in DCM, hexane was added, and the DCM was evaporated. The resulting solid was filtered.

[0090] 9-[(4-triphenylsilylphenyl)methyl]-2,3-dihydro-1H-carbazol-4-one (10.8 g, 0.0202 mol, yield: 63.0%) was obtained as a white solid.

[0091] Step 4: Alkylation of 9-[(4-triphenylsilylphenyl)methyl]-2,3-dihydro-1H-carbazol-4-one with methylmagnesium bromide

[0092] [ka]

[0093] A dry RB flask was charged with 9-benzyl-2,3-dihydro-1H-carbazol-4-one (6.18 g, 0.0224 mol) and 240 mL of THF under nitrogen. Methylmagnesium bromide (3.00 mol / L, 15.0 mL, 0.0449 mol) was added, and the reaction was stirred under nitrogen. After stirring over the weekend, the reaction was diluted with DCM, washed with water (a Grignard reaction was evident upon addition of water acidified with HCl to remove emulsion), then brine, dried over MgSO4, and evaporated. The material was chromatographed eluting with hexane / ethyl acetate (5%). Appropriate fractions were combined and evaporated.

[0094] 9-Benzyl-4-methyl-2,3-dihydro-1H-carbazol-9-ium bromide (2.19 g, 0.00618 mol, yield: 27.5%) was obtained.

[0095] Step 5: Reaction of the donor, bridge, and acceptor to form chromophore 1 An RB flask was charged with (3E)-2-chloro-3-(hydroxymethylene)cyclohexene-1-carbaldehyde (0.403 g, 0.00233 mol), 2-[3-cyano-4-methyl-5-phenyl-5-(trifluoromethyl)-2-furylidene]propanedinitrile (0.736 g, 0.00233 mol), and 12 mL of methanol. It was stirred under nitrogen at 40 °C for 1 hour. The methanol was evaporated, and then [4-[(4-methyl-2,3-dihydro-1H-carbazol-9-ium-9-yl)methyl]phenyl]-triphenyl-silane bromide (1.43 g, 0.00233 mol) and 12 mL of DCM were added. The reaction was stirred overnight at room temperature under nitrogen. The reaction was loaded onto a silica gel column and eluted with DCM. The appropriate fractions were combined and evaporated to recover 391 mg of clean carbazolium, 3307-C. The product and residue were chromatographed, eluting with DCM. The appropriate fractions were combined and evaporated to give 1.11 g of 3307-P, which was triturated in hot methanol, cooled, filtered, and washed with methanol to give 0.752 g of 3307-A after drying. The methanol was evaporated to give 3307-MeOH.

[0096] 2-[4-[(E)-2-[(3Z)-2-chloro-3-[(2Z)-2-[9-[(4-triphenylsilylphenyl)methyl]-2,3-dihydro-1H-carbazol-4-ylidene]ethylidene]cyclohexen-1-yl]vinyl]-3-cyano-5-phenyl-5-(trifluoromethyl)-2-furylidene]propanedinitrile (1.11 g, 0.00113 mol, yield: 48.4%): Chromophore 1 was obtained.

[0097] [ka]

[0098] Synthesis example 2:

[0099] Chromophore 2 was prepared using the donor group, 9-benzyl-4-methyl-2,3-dihydro-1H-carbazol-9-ium bromide, prepared in Synthesis Example 1, as follows: An RB flask was charged with (3E)-2-chloro-3-(hydroxymethylene)-5-(trifluoromethyl)cyclohexene-1-carbaldehyde (0.349 g, 0.00145 mol), 2-[3-cyano-4-methyl-5-phenyl-5-(trifluoromethyl)-2-furylidene]propanedinitrile (0.458 g, 0.00145 mol), and 12 mL of ethanol. The mixture was stirred under nitrogen at 40°C for 1 hour. The ethanol was evaporated, then [[4-[(4-methyl-2,3-dihydro-1H-carbazol-9-ium-9-yl)methyl]phenyl]-triphenyl-silane; bromide (809 mg, 0.00132 mol) and 12 mL of DCM were added. The reaction was stirred overnight at room temperature under nitrogen. The reaction was applied to a silica gel column and eluted with DCM. The appropriate fractions were combined and evaporated. The product and residue were chromatographed and eluted with DCM. The appropriate fractions were combined and evaporated. This was triturated with hot methanol, cooled, filtered, and washed with methanol.

[0100] 2-[4-[(E)-2-[(3Z)-2-chloro-5-(trifluoromethyl)-3-[(2Z)-2-[9-[(4-triphenylsilylphenyl)methyl]-2,3-dihydro-1H-carbazol-4-ylidene]ethylidene]cyclohexen-1-yl]vinyl]-3-cyano-5-phenyl-5-(trifluoromethyl)-2-furylidene]propanedinitrile (0.595 g, 0.000566 mol, yield 42.9%) was obtained.

[0101] [ka]

[0102] Specific examples of maximum absorption wavelengths for chromophore embodiments

[0103] Chromophore 1 was combined with propylene carbonate at 50% by weight to form a lyotropic composition. The composition was shear-conditioned between two glass substrates, and optical absorption analysis was performed across the visible and near-infrared spectra. Referring to Figure 1, the shear-conditioned sample (curve with an absorption peak near 1200 nm) exhibited a red shift as indicated by its peak value and an overall shift toward the near-infrared. As shown in Figure 1, the shear-conditioned sample, which was subsequently heated to 150°C for a short period to remove the solvent, did not exhibit such a red shift. Such a red shift is evidence of J-aggregate formation, which indicates at least partial self-alignment and anisotropy.

[0104] Chromophore 1 was combined with propylene carbonate at 50% by weight to form a lyotropic composition. The composition was placed between two glass substrates and subjected to polarized light microscopy. Referring to Figures 2a-2c, a red color was immediately observed in the shear-conditioned sample, indicating J-aggregate formation, at least partial self-alignment, and anisotropy. Figure 2c shows the sample between the two glass substrates before shear-conditioning. Clear micelle formation was observed, evidence of lyotropic properties. Figure 2b shows the shear-conditioned sample, which evidences a bright red color. Such a red color is evidence of J-aggregate formation, indicating at least partial self-alignment and anisotropy. In Figure 2c, the sample heated at 100°C to remove the solvent does not exhibit the red color.

[0105] It will be appreciated that changes could be made in the embodiments described above by those skilled in the art without departing from the broad inventive concept thereof. It is understood, therefore, that the invention is not limited to the particular embodiments disclosed, but that it is intended to cover modifications within the spirit and scope of the invention as defined by the appended claims.

Claims

1. A lyotropic composition comprising a nonlinear optical chromophore represented by the following general formula (I): D-Pi-A (I) wherein D represents an organic electron donor group, A represents an organic electron withdrawing group having an electron affinity greater than the electron affinity of D, and Π represents a Π bridge between A and D; The organic electron donor group D comprises a tetrahydrocarbazole moiety connected with a Π bridge at a carbon atom in the tetrahydro six-membered carbocyclic ring of the tetrahydrocarbazole moiety, wherein a hydrogen attached to a nitrogen of the five-membered ring of the carbazole moiety is replaced with a substituent R, where R represents a moiety other than hydrogen.

2. The tetrahydrocarbazole moiety is represented by the general formula (II): 【Chemical 1】 2. The lyotropic composition of claim 1, wherein R represents a moiety other than hydrogen.

3. 3. The lyotropic composition of claim 2, wherein R represents a moiety containing an aromatic ring.

4. 4. The lyotropic composition of claim 3, wherein R represents a moiety comprising an aromatic ring having a triaryl-substituted silyl substituent.

5. R represents a moiety containing an aromatic ring having a triaryl-substituted silyl substituent, as represented by general formula (III): 【Chemistry 2】 The lyotropic composition according to claim 4.

6. A is a group represented by the general formula (I a ) represents an electron-withdrawing group, 【Chemistry 3】 In the formula, R 2 and R 3 are each independently H, substituted or unsubstituted C 1 -C 10 alkyl, substituted or unsubstituted C 2 -C 10 Alkenyl, substituted or unsubstituted C 2 -C 10 Alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted carbocycle, substituted or unsubstituted heterocycle, substituted or unsubstituted cyclohexyl, and (CH 2 ) n -O-(CH 2 ) n 10. The lyotropic composition of claim 1, wherein n is a moiety selected from the group consisting of:

7. The nonlinear optical chromophore is represented by general formula (IV): 【Chemistry 4】 In the formula, R represents a substituent other than hydrogen, and R 2 and R 3 are each independently H, substituted or unsubstituted C 1 -C 10 alkyl, substituted or unsubstituted C 2 -C 10 Alkenyl, substituted or unsubstituted C 2 -C 10 Alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted carbocycle, substituted or unsubstituted heterocycle, substituted or unsubstituted cyclohexyl, and (CH 2 ) n -O-(CH 2 ) n (n is 1-10), wherein Y is independently hydrogen, halogen, alkyl, aryl, sulfur- or oxygen-linked alkyl or aryl groups, or any heteroatom-containing C 1 ~C 4 a and b each independently represent an integer of 0 to 3; z represents an integer of 1 to 3; and each arc A independently represents a substituted or unsubstituted C 2 -C 4 2. The lyotropic composition of claim 1, wherein the carbon atom bearing the Y substituent represents an alkyl group, which together with the carbon atom bearing the Y substituent and its two adjacent carbon atoms forms a cyclic group.

8. 10. The lyotropic composition of claim 1, further comprising one or more aprotic polar solvents.

9. 9. The lyotropic composition of claim 8, wherein the one or more aprotic polar solvents comprise propylene carbonate.

10. A thin film prepared from the lyotropic composition of claim 8.

11. 11. The thin film of claim 10, prepared by removing one or more solvents from the composition while the nonlinear optical chromophores are in a highly ordered and highly packed state.

12. An electro-optical device comprising the thin film according to claim 11.

13. A lyotropic composition comprising a nonlinear optical chromophore represented by the following general formula (I): D-Pi-A (I) wherein D represents an organic electron donor group, A represents an organic electron withdrawing group having an electron affinity greater than the electron affinity of D, and Π represents a Π bridge between A and D; The organic electron donor group D comprises a tetrahydrocarbazole moiety having the general formula (V): 【Chemistry 5】 In the formula, R 1 represents a moiety other than hydrogen, and R 2 represents a moiety selected from hydrogen, halide, alkoxy group, alkyl group (branched or unbranched), and aryl group; R 3 represents a moiety selected from hydrogen and alkyl groups (branched or unbranched); R 4 represents a moiety selected from hydrogen and alkyl groups (branched or unbranched); R 5 may optionally represent a fused aliphatic or aromatic ring having 3 to 5 carbon atoms.

14. R 1 14. The lyotropic composition of claim 13, wherein represents a moiety selected from the group consisting of branched alkyl groups and aryl groups.

15. R 1 15. The lyotropic composition of claim 14, wherein represents a moiety selected from substituted or unsubstituted benzyl groups.

16. R 1 15. The lyotropic composition of claim 14, wherein represents an aryl group substituted with a silyl group.

17. R 1 17. The lyotropic composition of claim 16, wherein represents an aryl group substituted with a triaryl-substituted silyl group.

18. R 1 18. The lyotropic composition of claim 17, wherein represents 4-(triphenylsilyl)-phenylmethyl.

19. 14. The lyotropic composition of claim 13, wherein A is selected from the following: 【Chemistry 6】 【Chemistry 7】 【Chemistry 8】

Images