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  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K50/00—Organic light-emitting devices
  • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
  • H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
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  • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
  • C07F9/02—Phosphorus compounds
  • C07F9/28—Phosphorus compounds with one or more P—C bonds
  • C07F9/50—Organo-phosphines
  • C07F9/5045—Complexes or chelates of phosphines with metallic compounds or metals
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  • C07—ORGANIC CHEMISTRY
  • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
  • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
  • C07F9/02—Phosphorus compounds
  • C07F9/547—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom
  • C07F9/553—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having one nitrogen atom as the only ring hetero atom
  • C07F9/576—Six-membered rings
  • C07F9/58—Pyridine rings
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  • H10K10/46—Field-effect transistors, e.g. organic thin-film transistors [OTFT]
  • H10K10/462—Insulated gate field-effect transistors [IGFETs]
  • H10K10/468—Insulated gate field-effect transistors [IGFETs] characterised by the gate dielectrics
  • H10K10/478—Insulated gate field-effect transistors [IGFETs] characterised by the gate dielectrics the gate dielectric comprising a layer of composite material comprising interpenetrating or embedded materials, e.g. TiO2 particles in a polymer matrix
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  • H10K85/141—Organic polymers or oligomers comprising aliphatic or olefinic chains, e.g. poly N-vinylcarbazol, PVC or PTFE
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  • H10K85/371—Metal complexes comprising a group IB metal element, e.g. comprising copper, gold or silver
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  • H10K2101/00—Properties of the organic materials covered by group H10K85/00
  • H10K2101/10—Triplet emission
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  • Y02E10/50—Photovoltaic [PV] energy
  • Y02E10/549—Organic PV cells

Definitions

• the invention relates to the use of mono- or binuclear metal complexes as emitters with variable emission colors, in particular in OLEDs (organic light-emitting diodes) and in other opto-electronic components.
• This new technology is based on the principle of OLEDs, Organic Light Emitting Diodes.
• the use of special metal-organic materials (molecules) many new optoelectronic applications, eg. As in the field of organic solar cells, organic field effect transistors, organic photodiodes, etc. from.
• OLEDs consist predominantly of organic layers, which are also flexible and inexpensive to manufacture.
• OLED components can be designed over a large area as lighting fixtures, but also as small pixels for displays.
• OLEDs Compared to conventional technologies, such as liquid crystal displays (LCDs), plasma displays or cathode ray tubes (CRTs), OLEDs have numerous advantages, such as a low operating voltage of a few volts, a thin structure of a few hundred nm, highly-efficient self-luminous pixels, high contrast and good resolution and the ability to display all colors. Furthermore, in an OLED light is generated directly when applying electrical voltage, instead of only modulating it.
• LCDs liquid crystal displays
• CRTs cathode ray tubes
• OLEDs are usually realized in layer structures.
• a basic structure of an OLED is shown in FIG. Due to the applied external voltage on a transparent indium tin oxide anode (ITO) and a thin metal cathode are injected from the anode positive holes and the cathode negative electrons. These differently charged charge carriers enter the emission layer via intermediate layers, which may also include here not drawn hole or electron blocking layers. There, the oppositely charged charge carriers meet at or near doped emitter molecules and recombine.
• the emitter molecules are usually incorporated into matrix molecules or polymer matrices (in, for example, 2 to 20% by weight), the matrix materials being chosen such that they also facilitate hole and electron transport.
• the selection of the matrix is of particular importance in the context of this invention, as will be explained below.
• This electroluminescent compound can then go into a specific electronic excited state, which is then converted as completely as possible and largely avoiding radiation-free deactivation processes by emitting light in the associated ground state.
• an electronic excited state which can also be formed by energy transfer from a suitable precursor exciton, comes, with a few exceptions, either a singlet or a triplet state, consisting of three sub-states into consideration.
• the triplet emitters suitable for triplet harvesting typically employ transition metal complex compounds in which the metal is selected from the third period of the transition metals. These are predominantly very expensive precious metals such as iridium or platinum. (See also H. Yersin, Top. Curr. Chem. 2004, 241, 1 and MA Baldo, DF O'Brien, ME Thompson, SR Forrest, Phys. Rev. B 1999, 60, 14422).
• the main reason for this lies in the high spin-orbit coupling (SBK) of the precious metal central ions (SBK constant Ir (III): “4000 cm “1 ; Pt (II): "4500 cm " 1 Ref: SL Murov, J.
• the emitter materials usually each have fixed emission colors. Thus, special requirements for emission colors can not be met in many cases. Of particular technological importance is z. B. the realization of white light emitters. For these, a very broad color spectrum superimposed from different primary colors has to be generated. Also in this area there is a deficit in the materials available so far. It is an object of this invention to tailor the emission colors of particular emitters. Brief description of the invention
• the invention relates to a method of shifting the emission wavelength of a metal complex emitting at a given wavelength to wavelengths greater than the given wavelength.
• the invention relates to a method for increasing the Stokes shift of an emitting metal complex.
• the Stokes shift of an emitting metal complex is the wavelength difference between the lowest-energy absorption (lowest-energy absorption peak) and the main emission maximum (emission peak).
• the Stokes shift for example, refers to the absorption from the singlet ground state into the lowest excited singlet state, as well as the emission from that excited singlet state to the singlet ground state.
• At least one metal complex which has the following properties: It has a given geometry in the area of the metal center in the electronic ground state and, in the electronically excited state, it aims at a changed geometry.
• the change in geometry depends on the environment of the emitting complex, in particular on a surrounding polymeric matrix.
• the method comprises the step of embedding the metal complex in a polymeric matrix.
• the polymeric matrix must be such that the geometry change of the embedded metal complex is possible as soon as it is electronically excited.
• the electronic excitation can be done for example by an optical light excitation or in an OLED by means of a hole-electron recombination. The nature of the geometry change will be explained below.
• the embedding of the metal complex in a polymeric matrix can be accomplished in any manner known in the art. It is possible to turn the metal complex into one already integrate existing matrix. Alternatively, the metal complexes can be incorporated into the matrix as part of the formation of the polymeric matrix, such as monomers or polymers. Preference is given to one-step reactions which are known to the person skilled in the art under the term "click reactions".
• a reaction for embedding the metal complex in a polymeric matrix comprises the following steps.
• a mixture of a first reactant in the form of an organic metal complex emitter and a second reactant in the form of a polymer, ie a means for immobilizing the metal complex, is applied to a solid support.
• the metal complex is cross-linked during the autocatalytic reaction of the first reactant with the second reactant in the forming multidimensional network.
• the formation of crosslinking at elevated temperature take place, preferably between 80 ° C to 120 ° C.
• the application of a mixture of both reactants to a solid support can be carried out by any of the methods known in the art, in particular by means of inkjet printing, dipping, spin coating, slot casting or knife coating.
• the first reactant and the second reactant have chemical groups that allow a fast and efficient covalent binding of the reactants to each other.
• anchor groups are also addressed here as anchor groups.
• first and second anchor group which are each complementary to one another, thus embedding (linking) a metal complex in the polymeric matrix, optionally be arranged on the metal complex or the unit forming the polymeric unit can.
• the attachment of the anchor groups to the organic ligand of the Metal complex can take place in any suitable position of the organic ligand of the metal complex, preferably not in the ortho position of the atom coordinating to the metal center.
• the metal complexes disclosed here preferably have at least one anchor group for embedding in the polymeric matrix.
• such reactions are preferred, in addition to the metal complex and the second reactant without the addition of another reactant, that is, at the most by a further application not disturbing catalyst manage.
• examples of such reactions are 1,3-dipolar cycloadditions, Diels-Alder reactions, nitrone-alkyne, nitrile-alkyne-alkyne, thiol-ene, thiol-in, thiol-isocyanate, tetrazole-alkene and others in the chemical literature known as click reactions.
• Preferred are those reactions which are catalyzed by the metal itself contained in the metal complex, which corresponds to an autocatalyzed cross-linking.
• the invention in a second aspect, relates to a composition which comprises a) at least one emitting metal complex having a geometry in the region of the metal center in the electronic ground state, which changes by electronic excitation and b) has a polymeric matrix.
• the metal complex is embedded in the polymeric matrix in such a way that the given geometry of the metal complex is changed by an electronic excitation (such as optical light absorption or hole-electron recombination).
• the metal complex used has an AE (Si-Ti) value between the lowest excited singlet (Si) and the underlying triplet (Ti) state of less than 2500 cm -1 , preferably less than 1500 cm " 1 , more preferably of less than 1000 cm " 1 , very particularly preferably of less than 500 cm "1 on.
• the emitting metal complex having a geometry given in the region of the metal center in the electronic ground state can be selected from the group consisting of mononuclear metal complexes and binuclear metal complexes.
• the metal complex is a copper, gold or silver complex.
• the mononuclear metal complex is a complex of Formula I and the binuclear metal complex is a complex of Formula II, shown below.
• the change of the given geometry by the electronic excitation is, in particular, the alteration of a tetrahedral coordination in the direction of a quadratic-planar coordination, which corresponds to a change with a planarization tendency.
• the electronically excited metal complex used in the process and present in the composition preferably has an emission lifetime of at most 20 ⁇ , preferably of at most 10. It is further preferred that the electronically excited, geometrically hardly distorted metal complex, ie z. B. embedded in relatively rigid crystalline form, an emission quantum yield of the solid of greater than 30%, preferably greater than 50%, more preferably greater than 70%.
• the Stokes shift can be increased by embedding the metal complex in the polymeric matrix by 10 nm, 50 nm, 100 nm, or 150 nm, so that a composition comprising a metal complex emitter can be provided having a correspondingly variable Stokes shift.
• the emission spectrum of the metal complex can be broadened by embedding in the polymeric matrix, in particular by 10 nm to 100 nm.
• an amorphous, soft polymer eg, polysiloxanes, polyethylene oxides
• a very rigid polymer eg, polyphenylene oxides
• the rigidity can be greatly increased by using crosslinkable polymers, wherein the crosslinking by means of thermal or UV activation or by the use of autocatalytic emitter materials, ie the metal center contained in the metal complex emitter serves as a catalyst, so that an autocatalyzed crosslinking takes place, can be triggered.
• the appropriate degree of "hardness" or "softness" of the polymeric Martrix can also be changed by annealing, for example.
• composition results in an emitter with altered color emission compared to the metal complex as a solid.
• Particularly preferred are compositions in which the embedded metal complex emits white light.
• the invention relates to opto-electronic devices comprising a composition of the type described herein.
• the composition according to the invention in the region of the emission layer is given by the ratio of the mass of the metal complex to the mass of the matrix material of between 1% by weight to 99% by weight. Preference is given to 2% by weight to 20% by weight.
• the invention relates to the use of a method of the type described herein or a composition of the type described herein in an optoelectronic device.
• opto-electronic device refers to organic light-emitting diodes (OLEDs), light-emitting electrochemical cells (LEECs or LECs), OLED sensors, in particular non-hermetically shielded gas and steam sensors, organic solar cells (OSCs), organic Field effect transistors, organic lasers, organic diodes, organic photodiodes and "down conversion" systems.
• OLEDs organic light-emitting diodes
• LEECs or LECs light-emitting electrochemical cells
• OLED sensors in particular non-hermetically shielded gas and steam sensors
• organic solar cells organic solar cells
• organic Field effect transistors organic lasers, organic diodes, organic photodiodes and "down conversion" systems.
• the invention relates to the provision and provision of compositions and their use, the compositions in particular having the following properties:
• the invention relates to a use of a metal complex having a given geometry in the electronic ground state region of the metal center, an altered geometry in the electronically excited state, and a 100% content in a microcrystalline or crystalline structure (ie, as a pure solid, for example as a crystal film) is present, in particular a metal complex according to formula I or II, in an opto-electronic component see.
• the metal complex used has an AE (Si-Ti) value between the lowest excited singlet (Si) and the underlying triplet (Ti) state of less than 2500 cm -1 , preferably less than 1500 cm -1 , more preferably of less than 1000 cm -1 , most preferably of less than 500 cm -1 .
• the emitting metal complex with a given geometry in the region of the metal center in the electronic ground state can be selected from the group consisting of mononuclear metal complexes and binuclear metal complexes.
• the metal complex is a copper, gold or silver complex.
• the mononuclear metal complex is a complex of Formula I and the binuclear metal complex is a complex of Formula II, shown below.
• the change in the given geometry by the electronic excitation is, in particular, the alteration of a tetrahedral coordination in the direction of a quadratic-planar coordination, which corresponds to a change with a planarization tendency.
• the electronically excited metal complex used in the composition and present in the composition preferably has an emission lifetime of at most 20 ⁇ s, preferably of at most 10. It is further preferred that the Metal complex has an emission quantum yield of the solid of greater than 45%, preferably greater than 70%, more preferably greater than 90%.
• the hole-electron recombination leads to a statistical average of 25% for the occupation of the singlet state (1 singlet path) and 75% for the occupation of AEi (Si-Ti) deeper triplet state (3 triplet paths).
• the Si-state excitation relaxes into the Ti state as a result of the inter-system crossing (ISC) process, which typically occurs faster in transition metal-organic complexes than in 10 "12 s Triplet state is very long for these metal complexes (eg 50 to 1000 or longer) Emitters with such long decay times are hardly suitable for OLED applications.
• ISC inter-system crossing
• Int (Si -> So) / Int (Ti -> So) represents the intensity ratio of the emission from the Si state and the Ti state
• k B is the Boltzmann constant
• T is the absolute temperature
• k (Si) / k (Ti) is the rate ratio of the (radiative) transition processes into the electronic ground state S 0 .
• this ratio is between 10 2 to 10 4 .
• Particularly preferred according to the invention are molecules with a rate ratio of 10 3 to 10 5 .
• AE (S 1 -T 1 ) stands for the energy difference AE 2 (Si-Ti) according to FIG. 2 b.
• Equation (2) should again be explained by a numerical example.
• Equation (2) For the assumed energy difference of and a cooldown of the fluorescent Si -
• the invention relates to a method for selecting complexes whose AE (Si-Ti) value between the lowest excited singlet (Si) and the underlying triplet state (Ti) is less than 2500 cm -1 , preferably less than 1500 cm "1 , more preferably less than 1000 cm " 1 , most preferably less than 500 cm "1 is.
• AE Si-Ti
• the determination of the AE (Si-Ti) value can be carried out either by quantum mechanical calculations by means of the computer programs known in the prior art (for example by means of turbomole programs using TDDFT and CC2 calculations) or, as further explained below - be carried out experimentally.
• the energy differences according to the invention can be achieved with AE (Si-Ti) smaller than 2500 cm “1 or smaller than 1500 cm " 1 or smaller than 1000 cm _1 or even smaller than 500 cm “1 .
• the energy AEE distance (S 1 -T 1) can be determined using the above equation (1) simple.
• any commercial Spectrophotometer can be used.
• a plot of the (logarithmic) intensity ratios ln ⁇ Int (Si-> So) / Int (Ti-> So) ⁇ measured against the reciprocal value of the absolute temperature T at various temperatures generally yields a straight line. The measurement is carried out in a temperature range from room temperature (300 K) to 77 K or to 4.2 K, wherein the temperature is adjusted by means of a cryostat.
• the intensities are determined from the (corrected) spectra, where Int (Si-> So) and Int (Ti-> So) represent the integrated fluorescence or phosphorescence band intensities, respectively, which can be determined by means of the programs belonging to the spectrophotometer.
• the respective transitions (band intensities) can be easily identified since the triplet band is at lower energy than the singlet band and gains in intensity with decreasing temperature.
• the measurements are carried out in oxygen-free dilute solutions (about 10 -2 mol L -1 ) or on thin films of the corresponding molecules or on doped with the corresponding molecules films.
• a solution is used as the sample, it is advisable to use a solvent or solvent mixture which forms glasses at low temperatures, such as 2-methyltetrahydrofuran, butyronitrile, toluene, ethanol or aliphatic hydrocarbons.
• a film is used as a sample, the use of a matrix having a significantly higher singlet and triplet energy than that of the metal complexes (emitter molecules) according to the formulas I or II, z.
• PMMA polymethylmethacrylate
• the straight line slope is the energy gap can be determined directly.
• the AE (Si-Ti) value then corresponds approximately to the energy difference between the high-energy rising edges of the fluorescence or phosphorescence band.
• Another method of determining the AE (Si-Ti) value is by measuring the emission decay times with a commercial meter.
• the emission lifetime t av as a function of temperature using a cryostat for the Range between 4.2K or z. B. 20 K and 300 K measured.
• the formula (4) and the emission lifetime for the triplet state ⁇ ( ⁇ ) measured at low temperature it is possible to fit the measured values with the formula (4), and the AE (Si-Ti) value is obtained.
• the x (Ti) value is often determined by the plateau obtained when plotting the measured values, and if such a plateau is formed, cooling to 4.2 K is usually no longer necessary).
• the four-coordinate complexes according to formulas I and II have an approximately tetrahedral coordination in the region of the metal center in the electronic ground state.
• Upon optical excitation or excitation by hole-electron recombination into an electronic state with pronounced metal-to-ligand charge-transfer character and the associated formal oxidation of the metal atom there are significant changes in the geometry of the complex in the direction of a square planar coordination, ie towards a "planarization" of the molecule with respect to a metal center of the formulas I and / or both metal centers of the formula II
• This process reduces the energies of the emitting states due to the geometry change of the excited state As a result, the emission is shifted to longer wavelengths (eg, blue to green or to yellow or to red), and the spectral widths of the emission bands are increased (eg, the Stokes shift between absorption and emission). around 10 to 100 nm) .
• the Emi ssion both the spectral blue, green and
• the geometry change that occurs through the excitation process can be controlled. That is, a small change in geometry leads to a likewise small shift of the emission colors and comparatively small broadening of the emission bands, so that the emission behavior of the metal complex can correspond approximately to that of the rigid solid or the behavior in frozen solutions.
• the z For medium geometry changes, the z.
• color shifts and broadening of the emission bands by several tens of nanometers are obtained, while in very "soft" environments of the emitter molecules (eg, even in fluid solutions), very large changes in geometry and hence large color shifts (e.g. 200 nm) as well as band broadening (eg up to 100 nm) can be carried out (see also the example shown in FIG.
• the molecularly possible twists can be influenced within wide limits, but also largely suppressed.
• the extent of the possible distortions can be determined on the one hand by quantum mechanical calculations using the computer programs known in the prior art (eg by means of turbomole or Gaussian programs with execution of DFT or TDDFT directions).
• the determination of the emission band shift and broadening can also be done experimentally. For this purpose, the emission behavior of the complex in solid and then in solution is investigated. Of the Comparison of the emission spectra then leads directly to the desired statement about the severity of the emission band change.
• High rigidity is present when using the crystalline solid (eg, as a 100% emitter material, such as in an OLED).
• the examples given show ( Figure 3, Table 1) that on this basis a blue light emission is easily accessible.
• the emitter molecules are doped in polymer matrices, for example in concentrations of 2 to 20 percent by weight. Such dopants are used, for example, in emission layers for efficient OLEDs.
• the individual environment of an emitter molecule is decisive for whether the maximum possible change in geometry predetermined by the chemical structure of the complex can actually take place. In principle, this individual environment in a given matrix is not identical for each emitter molecule. That is, the distribution of installation situations is very inhomogeneous. In other words, there will be emitter complexes in relatively small or rigid mounting gap, but also (other) complexes will find a relatively large space. This eventually leads to a range of geometry modification possibilities. As a result, as desired, areas of color shifts and hence emission band broadening will result.
• the center of gravity of a color shift and the width of the associated emission band is given by the polymeric matrix used.
• the most different size distributions of the gaps in the matrices and the most diverse rigidities can be achieved by a variation and / or pretreatment of the polymers.
• amorphous, soft polymers eg, polysiloxanes, polyethylene oxides
• mid-rigid eg, polymethyl methacrylates (PMMA), polycarbonates
• very rigid polymers e.g. Polyphenylene oxides
• the rigidity can also be greatly increased by using crosslinkable polymers, wherein the crosslinking by means of thermal or UV activation or by the use of autocatalytic emitter materials, ie the metal center contained in the metal complex emitter serves simultaneously as a catalyst, so that an autocatalyzed cross-linking takes place, is triggered ,
• PMMA is a semi-crystalline polymer in small areas.
• T g glass transition temperature
• polymer matrices are characterized by voids between the (very large) polymer molecules.
• the sizes and distributions of these free spaces vary with the type of polymer, the pretreatment and the temperature difference relative to Tg . Statements about these properties are important for many technological areas (eg rates of drug release).
• extensive investigations and classifications have been carried out for more than five decades (for example, F. Fujita, Adv. Polym., 1961, 3, 1, D. Ehlich, H. Sillescu, Macromolecules 1990, 23, 1600, MT Cicerone, FR Blackburn , MD Ediger, Macromolecules 1995, 28, 8224).
• the expressiveness (frequency and size) of the free spaces can be z.
• M Cu, Ag or Au
• L - L m suitable ligands, which are defined below.
• the ligands can be either the same or different.
• the ligands can either be monodentate ligands or be interconnected and form polydentate, especially bidentate, ligands.
• Formulas I and II contain either four monodentate ligands or two bidentate ligands or one bidentate and two monodentate ligands.
• phosphine and Arsanliganden and ligands having at least one N-donor atom use.
• the ligands can be either neutral or simply negatively charged.
• X in formula II is a suitable bridge, such as.
• aryl e.g., phenyl, tolyl, naphthyl, C 6 F 5
• heteroaryl eg, furyl, thienyl, pyridyl, pyrimidyl
• alkyl, aryl, alkenyl and alkynyl radicals may also be deuterated, halogenated or substituted in some other way (eg with other alkyl, aryl, alkenyl and alkynyl functions).
• the bridge can also be:
• the complexes may have the following charges: -1, 0, and +1.
• the charge is compensated by a suitable counterion.
• metal cations in particular alkali metals, NH + , R 4 + , PH 4 + , PR 4 + ,
• alkyl eg Me, Et, n-Pr, i-Pr, n-Bu, t-Bu, adamantyl
• aryl eg phenyl, tolyl, naphthyl, C 6 F 5
• Heteroaryl eg, furyl, thienyl, pyridyl, pyrimidyl
• alkenyl eg
• As anions may be used: halides, PF 6 , BF 4 , AsF 6 , SbF 6 , C 10, N0 3 , BR 4 ,
• R ⁇ R ' and R '" are defined as R and can also be H.
• alkyl eg Me, Et, Pr, i-Pr, n-Bu, t-Bu, adamantyl
• aryl eg phenyl, tolyl, naphthyl, C 6 F 5
• Heteroaryl eg furyl, thienyl, pyridyl, pyrimidyl
• alkenyl eg
• R ', R ", R'" are defined as R and also H.
• alkyl, aryl, alkenyl and alkynyl radicals may also be deuterated, halogenated or substituted in some other way (eg with other alkyl, aryl, alkenyl and alkynyl functions).
• R ', R "and R'" are defined as R and also H.
• the R's in the structures may be the same or different.
• the charged phosphine ligands may be, for example, the compounds shown below.
• the radical R is an organic substituent and defined as the rest R in the neutral monodentate phosphine ligands.
• the R's in the structures may be the same or different.
• the phosphorus can be replaced by an arsenic atom.
• organic groups R (X) and R, Rl, R2 and R3 may be identical or independent and are selected from the group consisting of: hydrogen, halogen and groups which via oxygen (-OR), nitrogen (- R 2 ) or silicon atoms (-S1R 3 ), as well as alkyl, aryl, heteroaryl and alkenyl groups or substituted alkyl, aryl, heteroaryl and alkenyl groups having substituents such as halogens or deuterium, alkyl groups and others in general known donor and acceptor groups such as tertiary amines, carboxylates and their esters, and CF 3 groups.
• the organic groups can also lead to annellated ring systems.
• ⁇ -diimine ligands which advantageously have the following structure:
• ⁇ -Diimine ligands can consist of both five- or six-membered rings whose components Z1-Z4 are either the fragments CR (X) or N.
• R (X) organic radical.
• R (X) and R 1, R 2 and R 3 can be identical or independent and can be selected from the group comprising: hydrogen, halogen and groups which are bonded via oxygen (-OR) , Nitrogen (- R 2 ) or silicon atoms (-S1R 3 ) are bonded, and alkyl, aryl, heteroaryl and alkenyl groups or substituted alkyl, aryl, heteroaryl and alkenyl groups having substituents such as halogens or deuterium, alkyl groups and other well-known donor and acceptor groups such as tertiary amines, carboxylates and their esters, and CF 3 groups.
• the organic groups can also lead to annellated ring systems.
• Y can be either NR, O or S. This definition also includes the possibility that A or B do not form a cycle but are open-chain.
• # Denotes the atom attached to the second unit.
• * Denotes the atom that undergoes complex binding).
• the units A and B can also be connected by an additional bridge so that a new aromatic or aliphatic cycle is formed.
• R (X) and R1-R10 are each organic groups R which may be the same or different. These organic groups can be selected from the group comprising: hydrogen, halogen and groups which are bonded via oxygen (-OR), nitrogen atoms (- R 2 ) or silicon (-S1R 3 ), and also alkyl, aryl, heteroaryl and alkenyl groups or substituted alkyl, aryl, heteroaryl and alkenyl groups having substituents such as halogens or deuterium, alkyl groups and other well-known donor and acceptor groups, such as tertiary amines, carboxylates and their esters, and CF 3 groups.
• the organic groups can also lead to annellated ring systems.
• substituents that are directly adjacent to the coordinating N atoms are sterically less demanding groups, so that sufficient flexibility of the metal complexes remains.
• substituents which consist of only one atom (eg H, Cl, Br, I) and methyl and ethyl groups are sterically less demanding. Larger substituents lead to an excessive stiffening of the complexes and greatly reduce the molecular flexibility or even prevent the corresponding effect.
• substituents whose space requirement or size does not significantly exceed that of a methyl group are particularly preferred.
• R (X) organic radical.
• R (X) organic radical.
• R (X) organic radical.
• R (X) organic radical.
• R (X) organic radical.
• R (X) organic radical.
• R (X) can be identical or independent and can be selected from the group comprising: hydrogen, halogen and groups which via oxygen (-OR), nitrogen (- R 2 ) or silicon atoms (- SiR 3 ) are bonded, and alkyl, aryl, heteroaryl and alkenyl groups or substituted alkyl, aryl, heteroaryl and alkenyl groups having substituents such as halogens or deuterium, alkyl groups and others well known donor and acceptor groups such as tertiary amines, carboxylates and their esters, and CF 3 groups.
• the organic groups can also lead to annellated ring systems.
• Y 0, S or NR.
• N-B-N The single negatively charged N-donor ligand may be one of the molecules shown below:
• R (X) organic radical.
• R (X) and R, Rl and R 2 can be identical or independent of one another and can be selected from the group comprising: hydrogen, halogen and groups which are bonded via oxygen (-OR) , Nitrogen (- R 2 ) or silicon atoms (-S1R 3 ) are bonded, and alkyl, aryl, heteroaryl and alkenyl groups or substituted alkyl, aryl, heteroaryl and alkenyl groups having substituents such as halogens or deuterium, alkyl groups and other well-known donor and
• Acceptor groups such as tertiary amines, carboxylates and their esters, and CF 3 -
• the organic groups can also lead to annellated ring systems.
• Y is either O, S or NR.
• the bridge B ' is a neutral bridge such as -CH 2 -, -CR 2 -, -SiR 2 -, -NH-, -NR-, -O-, or -S-; (R is again generally an organic group and defined as described above for the neutral monodentate phosphane ligands.)
• Nitrogen ligands containing the bridge B ' are abbreviated as N-B'-N, and those not containing the bridge as NN.
• the ligands ⁇ * ⁇ are preferably the following ligands:
• Y CR 3 , CR 4 or N
• R 1, R 5 can each independently be hydrogen, halogen or substituents which are bonded via oxygen (-OR), nitrogen (-R 2 ) or silicon atoms (-SiR 3 ) and also alkyl (also branched or cyclic), Aryl, heteroaryl, alkenyl, alkynyl or substituted alkyl (also branched or cyclic), aryl, heteroaryl and alkenyl groups having substituents such as halogens or deuterium, alkyl groups (also branched or cyclic), and others well-known donor and acceptor groups such as amines, carboxylates and their esters, and CF 3 groups.
• R3-R5 can also lead to fused ring systems.
• a metal complex has at least one, for cross-linking with the polymeric matrix, preferably two or more anchor groups.
• the anchor groups on the organic ligands of the metal complex can in principle take place in any position of the organic ligand of the metal complex, preferably not in the ortho position of the atom coordinating to the metal center.
• the substituents of the structures ⁇ * ⁇ of the copper (I) complexes, in particular anchor groups, can be arranged at any point of the structure.
• FIG. 1 Basic structure of an OLED. The illustration is not drawn to scale.
• FIG. 2 For explaining the electroluminescent behavior.
• AEi Si-Ti
• ⁇ ( ⁇ ) represents an example, b diagram for explaining the electroluminescence behavior of metal complexes with comparatively small energy difference AE 2 (Si-Ti), ie, for example, less than 2500 cm -1 , between the lowest excited triplet state and the overlying singlet state.
• An example of b is presented in FIG. ii (ISC) and x 2 (ISC) represent the inter-system crossing times.
• Figure 3 shows the absorption spectrum and emission spectra of Cu (POP) (pz 2 BH 2 ).
• Figure 4 shows a general scheme for linking organic metal complexes (first reactant) with monomers, oligomers or polymers (second reactant), each carrying a corresponding anchor group, which allows the cross-linking (cross-linking) of the metal complex in the polymeric matrix.
• the reaction product is referred to herein as Composit.
• Figure 5 shows selected examples of anchor groups of first and second anchor group species (each arranged in rows).
• First and second anchor group species are addressed here as anchor A and anchor B, respectively.
• anchor A the anchor A shown here
• anchor B the anchor B corresponding to the second or first anchor group species represent. Examples
• Figure 3 shows absorption and emission spectra of Cu (POP) (pz 2 BH 2 ). These were taken at room temperature. Embedded in a polymeric matrix (shown in the figure) results in a strong color shift of the emission.
• the emission lifetime at T 2 K (measured in powder) is 630 s. Due to the very strong increase in the lifetime by cooling can be concluded that the presence of singlet harvesting.
• the emission lifetime at T 2 K (measured in powder) is 650 ⁇ . Due to the very strong increase in the lifetime by cooling can be concluded that the presence of singlet harvesting.
• Embedding the Cu (I) complex in various polymeric matrices results in a different color shift of emission, which can be adjusted and adjusted by choosing different rigid polymer matrices.
• crosslinkable polymers such as GAP (glycidyl azide polymer)
• the rigidity of the matrix can be greatly increased, in which case the crosslinking by using autocatalytic crosslinking, ie the metal center contained in the metal complex emitter serves as a catalyst of crosslinking, so that an autocatalyzed cross-linking takes place, can be triggered.
• the copper-catalyzed click reaction between a terminal or activated alkyne as the first click group and an azide as the second click group was used in this case. Since the metal complex emitter carries at least two, in this example three alkyne units, which are also referred to herein as first anchor groups, is carried out by autocatalyzed reaction with a second reactant having at least two complementary azide units, here also as second anchor groups the formation of a multi-dimensional network.
• the metal complex emitter is cross-linked in the multidimensional network that forms, ie at least two bonds of the metal complex with the multidimensional network formed by the second reactant, in this example the glycidyl azide polymer with n bonds, form.
• this can be a ladder-like (two-dimensional) structure in which two network strands are linked by at least one metal complex emitter which forms at least one covalent bond with one of the strands.
• complicated three-dimensional networks are possible as a product of this reaction, which comprise cross-linked metal complex emitters by means of a variable number of network strands.
• the cross-linked metal complex emitter is thus immobilized in multi-dimensional networks and fixed and stabilized with respect to its geometry change.
• the transition probabilities for non-radiative processes are reduced by rotation and twisting: the emission quantum efficiency of the emitters is increased, while the fixation leads to a maximum utilization of the energetic distance between the ground and the first excited state compared to the "free”, ie Since the occupation of rotational and vibrational states is less likely and the energy difference between the ground and the first excited state (direct vertical arrangement of the potential curves, see Franck-Condon principle) is maximized. Immobilization makes it possible to shift the emission of a given free, ie non-crosslinked, emitting metal complex in the direction of or into the blue spectral range.
• the process comprises at least the following steps: A mixture of a first reactant in the form of an organic metal complex emitter and a second reactant in the form of a polymer, ie a means for immobilizing the metal complex, is applied to a solid support.
• the metal complex is cross-linked during the autocatalytic reaction of the first reactant with the second reactant in the forming multidimensional network.
• the formation of the crosslinking is preferably carried out at elevated temperature, preferably between 80 ° C to 120 ° C.
• the application of a mixture of both reactants to a solid support can by means of all methods known in the art, in particular by means of inkjet printing, dipping, spin coating, slot casting or knife coating (knife coating).
• the metal complexes described herein can also be used as emitters 100%, ie without the presence of a polymeric matrix. They are then present in a micro-crystalline structure and can be characterized in particular by high emission quantum yields. This behavior is particularly favorable compared to the many other known solids (100% materials). Because in the latter usually takes place a pronounced extinction of the emission. This is justified, as is known to those skilled in the art, by the fact that processes of radiationless energy transfer (Förster-Dexter transfer) can take place from one excited molecule to the neighboring molecule and further to the next neighboring molecule, etc. As a result, the always present impurities are reached at which a deletion of the emission can take place.
• Förster-Dexter transfer processes of radiationless energy transfer
• the polymer matrix or its rigidity is chosen so that a slight complex distortion can occur.
• a non-radiative energy transfer can be greatly reduced or prevented.
• high emission or electroluminescent quantum yields can be achieved even at high emitter doping concentrations (above 30 and preferably above 50% by weight, copper complex / polymer material).
• High emitter concentrations in an OLED application then allow an increase in the efficiency at high brightness or at high current density (reduction of the roll-off of the efficiency with increasing current density).
• the emission quantum yield in the solid is at least 45% (eg Cu (POP) (pz 2 BH 2 ), preferably at least 70% (eg Cu 2 Br 2 (PPh 3 ) 2 (py) 2 ) , more preferably at least 90% (eg, Cu (POP) (pz 4 B) and Cu (POP) (pz 2 Bph 2 )).
• the invention also relates to metal complexes, in particular according to the formulas I and II, in which a slight distortion in the excited state occurs in comparison to the geometry of the ground state, whereby the radiationless energy transfer between the emitter complexes is reduced or prevented.

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