CN105392861A - Extended singlet harvesting for oleds and other optoelectronic devices - Google Patents

Abstract

The invention relates to a light-emitting transition metal complex, which emits light from a singlet state (S1) (singlet harvesting) and in addition, in order to shorten the total emission duration, also emits light from an energetically inferior triplet state (T1), the occupancy of the states and the resulting emissions being in a thermal balance.

Description

Gather in the crops for OLED and the expansion singlet state of other photoelectronic devices

Technical field

The present invention relates to transition metal complex in OLED and in other photoelectronic devices as the application of radiator.

Background technology

At present, have employed new method in Screen Technology and lighting technical field.Thickness can be manufactured lower than the flat-panel screens of 0.5mm or light-emitting area.The salient point of these methods is a lot of attracting characteristic.Such as light-emitting area can be manufactured the wallpaper (Tapete) with very little energy consumption, and the color/graphics of irrealizable colour fastness (Farb-Echtheit) so far, brightness and viewing angle independence can be had with very little weight and low-down power consumption manufacture.Screen can be designed to miniscope or have several rigid form of square meter area or the large-screen of flexible form, but also can be designed to transmissive display or reflective display.In addition, simple and cost-effective manufacture method can also be used, as silk screen printing or ink jet printing.Thus, very economical manufacture can be realized compared with traditional flat screen.This new technology based on OLED, i.e. the principle of Organic Light Emitting Diode.In addition, much new optoelectronic applications occasion, the salient point of such as, application scenario in the fields such as organic field-effect transistor, organic photosensitive diode is just to employ special metallo organic material (atom).

Thus, particularly known for OLED field, this arrangement has been important at present economically, because started to carry out batch micro operations.This OLED mainly comprises multiple organic layer, and these organic layers also can flexibly and manufacture economically.OLED can be designed to twinkler in large area, but also can be designed to the picture point of indicating meter smaller.

Relative to conventional art, as such as liquid-crystal display (LCD), plasma display or cathode-ray tube display (CRT), OLED has a lot of advantages, as only having the little operating voltage of several volts, only having the ability of thin structure, efficient self luminous picture point, high-contrast and the good resolving power of hundreds of nm and display all colours.In addition, in OLED, directly produce light when applying voltage, instead of the modulation of polarization optics can only be carried out.

Overview about OLED function is such as being documented in German Weinheim, Wiley-VCH, the H.Yersin published for 2008, Top.Curr.Chem.2004,241,1 and H.Yersin, Ed., in " HighlyEfficientOLEDswithPhosphorescentMaterials ".

Since reported first OLED (is such as shown in Tangetal., Appl.Phys.Lett.1987,51,913) since, these devices have particularly obtained further development in used emitter material, wherein, particularly concern was being caused to be utilize triplet state gather in the crops the triplet emitters of effect (Triplett-Harvesting-Effekt) or also have the radiator of other phosphorescence and utilize singlet state to gather in the crops the singlet state radiator of effect (Singulett-Harvesting-Effekt) especially in recent years.

For be suitable for triplet state results triplet emitters in usually use transition metal complex, in described complex compound, metal is selected from the period 3 of transition metal.Here preferably very expensive precious metal, as iridium, platinum or also have gold (to this also see H.Yersin, Top.Curr.Chem.2004,241,1 and M.A.Baldo, D.F.O ' Brien, M.E.Thompson, S.R.Forrest, Phys.Rev.B1999,60,14422).This major cause is, the high-spin orbit coupling (SBK) (SBK constant Ir (III): ≈ 4000cm of precious metal central ion ^-1; Pt (II): ≈ 4500cm ^-1; Au (I): ≈ 5100cm ^-1; Reference: S.L.Murov, J.Carmicheal, G.L.Hug, HandbookofPhotochemistry, 2 ^ndedition, MarcelDekker, NewYork1993, p.338ff).Due to the characteristic on this quantum mechanics, allow when there is no SBK for the triplet state of optical transition total ban-singlet state transition, and reach the short emission lifetime of a few μ s needed for OLED application.

Except triplet state results, also set up another mechanism in recent years, described mechanism achieves making full use of all produced exciton (Exziton) in OLED equally.This mechanism is called as singlet state results (see H.Yersin, A.F.Rausch, R.Czerwieniec, T.Hofbeck, T.Fischer, Coord.ChemRev.2011,255,2622).In singlet state results, the same with in triplet state results, occupy lowest excited triplet state.But now launch is not by minimum triplet state T ₁occur, but by hot reset by lowest excited singlet state S ₁occur (see Fig. 1).This process is called as hot activation delayed fluorescence (TADF, thermallyactivateddelayedfluorescence).In order to realize this process, need such as to be less than about 2000cm ^-1less singlet state-triplet energies difference Δ E (S ₁-T ₁).Particularly have the molecule of high charge transfer characteristic, such as copper compound is suitable for use as radiator (H.Yersin, A.F.Rausch, R.Czerwieniec, T.Hofbeck, T.Fischer, Coord.ChemRev.2011,255,2622).Effect is gathered in the crops by utilizing singlet state, the radiator of Cu (I) base can be formed, the transmitting quantum yield (Emissionsquantenausbeute) of described transmitting physical efficiency realization more than 80% is (see R.Czerwieniec, J.Yu, H.Yersin, Inorg.Chem., 2011,50,8293).

The object of the invention is, provide a kind of and there is the emitter material for photoelectron device improving characteristic.Described new emitter material such as allows to utilize all excitons produced, and alleviates the Roll-Off effect damaging efficiency or the work-ing life of improving optoelectronic equipment.

Summary of the invention

Surprisingly, object of the present invention realizes by expanding singlet state recited above results effect.Had been found that suitable radiator molecule, this radiator molecule has little singlet state-triplet energies difference and has short radioactivity triplet lifetime due to Quantum geometrical phase.Make use of singlet state results thus, and additionally add triplet state transmitting according to the present invention, to shorten the radioactivity life-span of radiator molecule further.

Schematically show the energy level schematic diagram of radiator in FIG.The optical physics electroluminescence characters of this radiator is described according to this energy level schematic diagram.Here the electron-hole as such as carried out in optoelectronic devices is compounded in statistical average has 25% cause occupying singlet state (1 singlet state path) and have 75% to cause occupying low Δ E ₁(S ₁-T ₁) triplet state (3 triplet state paths).Enter S ₁exciting such as, because intersystem crossing (ISC) process (is for transition metal-organic emitter usually than instant fluorescent reaction sooner, <10 of state ^-10s) relax towards T ₁state.From directly carrying out launching (triplet state results), or entered the ground state of electronics via singlet state by hot activation delayed fluorescence reaction (TADF) here.

Can improve prior art according to the present invention, its mode is, selects such compound, and described compound has and is less than 2000cm between lowest excited singlet state and the triplet state lower than it ^-1Δ E (S ₁-T ₁) value, and there is effective (effizient) Quantum geometrical phase, described Quantum geometrical phase causes lowest excited triplet state to have the short radiation emissions life-span.Due to this little energy difference Δ E (S ₁-T ₁), according to Boltzmann's distribution in other words according to heat energy k _bt can realize S ₁state is from T ₁the hot reset (R ü ckbesetzung) of state.Therefore, thermal equilibrium that is a kind of and temperature correlation is established.Thus, by S ₁state is set out and can be realized hot activation luminescence.Can realize directly launching approach from lowest excited triplet state additionally by effective Quantum geometrical phase.Thus, for luminescence, provide the transmitting approach by triplet state and singlet state.

This mechanism can be called knockdown triplet state-singlet state results.Energy difference Δ E (S ₁-T ₁) less and Quantum geometrical phase is more effective, this effect is more remarkable.Therefore such radiator is preferred, and described radiator has and is less than 2000cm between lowest excited singlet state and the triplet state under it ^-1, be preferably less than 1000cm ^-1, and be particularly preferably less than 300cm ^-1Δ E (S ₁-T ₁) value, and have and be less than 100 μ s, be preferably less than 50 μ s, be more preferably less than 20 μ s and be particularly preferably less than the triplet lifetime of 5 μ s.

The average emitted life-span of radiator can be expressed by following equation approx:

${\mathrm{\&tau;}}_{therm}=\frac{3+\exp (-\frac{\mathrm{\&Delta;}E(S_1-T_1)}{k_{B}T})}{\frac{3}{\mathrm{\&tau;}\left(T_1\right)}+\frac{1}{\mathrm{\&tau;}\left(S_1\right)}\exp (-\frac{\mathrm{\&Delta;}E(S_1-T_1)}{k_{B}T})}---\left(1\right)$

Wherein τ (T ₁) be the phosphorescent lifetime of lowest excited triplet state, τ (S ₁) be lowest excited singlet state fluorescence lifetime (for this investigation supposition, τ (T ₁) and τ (S ₁) be temperature correlation).τ _thermbe the average emitted life-span, the described average emitted life-span is by state T ₁and S ₁determine (see Fig. 1).Other parameters define above.Equation 1 is at supplementary condition Δ E (II-I) <<k _bt and Δ E (III-I) <<k _bthe reduced form of equation 3 (seeing below) under T.Parameter Δ E (II-I) and Δ E (III-I) will define in conjunction with equation 3.

Equation 1 should be illustrated by example.If assuming that energy difference is Δ E (S ₁-T ₁)=500cm ^-1, and the fluorescigenic S of supposition ₁the fall time of state is 500ns, and phosphorescent T ₁the fall time of state supposition is 10 μ s, and can obtain (described two states) transmitting fall time is τ under envrionment temperature (300K) _therm≈ 6 μ s.This fall time is shorter than known TADF-Cu (I) singlet state radiator.On the contrary, if in this example, transmitting is only limitted to singlet state and launches, in other words, assuming that triplet lifetime value is such as that 500 μ s (be exactly like this for invalid Quantum geometrical phase practical situation) are (see R.Czerwieniec, J.Yu, H.Yersin, Inorg.Chem., 2011,50,8293), then τ can be obtained at 300K _thermthe transmitting fall time of ≈ 17 μ s.Because basis present invention reduces phosphorescent lifetime τ (T ₁), in this example, launch and be acutely reduced to about 1/3rd at ambient temperature fall time.

Generally speaking, when adopting knockdown triplet state-singlet state harvest method, in the ideal case, can catch all, in other words maximum 100% exciton and convert thereof into light by utilizing triplet state and singlet state to launch.In addition, transition metal radiator according to the present invention also has such transmitting fall time, described transmitting is launched with simple triplet state fall time or hot activation singlet state launch compared with obviously shorter.Therefore, opto-electronic device is particularly suitable for according to the application of the present invention to corresponding complex compound.

The present invention also relates to a kind of for selecting the method for radiator in one aspect of the method, and described radiator is at lowest excited singlet state (S ₁) and the triplet state (T that is positioned under it ₁) Δ E (S ₁-T ₁) value is less than 2000cm ^-1, be preferably less than 1000cm ^-1, be particularly preferably less than 300cm ^-1, and its triplet lifetime is less than 100 μ s, is preferably less than 50 μ s, is more preferably less than 20 μ s, is particularly preferably less than 5 μ s.

To Δ E (S ₁-T ₁) value and triplet state (T ₁) the sub-Mechanics Calculation of determination throughput in radioactivity life-span utilize known computer program (such as utilizing Amsterdam Density functional bag (AmsterdamDensityFunctionalPakets – ADF) when introducing Quantum geometrical phase) to carry out, or to be undertaken by the mode (experimentell) of testing as also will illustrated below.

Energy difference Δ E (S ₁-T ₁) can assign to describe by the so-called commutative product being multiplied by coefficient 2 by quantum-mechanical mode approx.Its value directly depends on the significance of so-called charge transfer characteristic in the presence of metal/d track and part-π * track.In other words, the transition of electron between different tracks represents the charge transfer transition (MLCT transition) of metal to part.MO overlap recited above is less, and the charge transfer characteristic of electronics is more remarkable.Now, this charge transfer characteristic is with the reduction of exchange integral and is thus and energy difference Δ E (S ₁-T ₁) reduction to be associated.Due to (quantum-mechanical) characteristic of this optical physics, can reach and be less than 2000cm according to of the present invention ^-1or be less than 1000cm ^-1or be even less than 300cm ^-1energy difference Δ E (S ₁-T ₁).

Triplet state T ₁the radioactivity life-span pass through T ₁singlet state characteristic component (Anteil) in wave function is determined, and singlet state characteristic component is larger, and the described radioactivity life-span is shorter.Described singlet state characteristic admixture is with Quantum geometrical phase.(see A.F.Rausch, H.Yersin, H.H.H.Homeier, Top.Organomet.Chem.2010,29,193.).This admixture of Quantum geometrical phase validity and also have triplet lifetime can determine by means of Quantum mechanical calculation program (such as ADF bag) thus in other words.According to the present invention, the value of triplet lifetime is less than 100 μ s, is preferably less than 50 μ s, is more preferably less than 20 μ s, and is particularly preferably less than 5 μ s.

Also Δ E (S can be determined by test in the following manner ₁-T ₁):

For given radiator, following equation determination energy difference Δ E (S can be used ₁-T ₁):

ln{Int(S ₁→S ₀)/Int(T ₁→S ₀)}＝ln{k(S ₁)/3k(T ₁)}–(ΔΕ(S ₁-T ₁)/k _B)(1/T)(2)

K (S ₁) and k (T ₁) be S ₁state or T ₁the radioactivity inactivation rate of state.For intensity I nt (S ₁→ S ₀) and Int (T ₁→ S ₀) measurement can adopt any spectrophotometer.By (the asking logarithm) intensity ln{Int (S recorded at different temperature ₁→ S ₀)/Int (T ₁→ S ₀) inverse that is graphically plotted in absolute temperature T can obtain straight line usually.Described measurement is performing from room temperature (300K) to 77K or in the temperature range of 4.2K, and wherein said temperature is arranged by cryostat common on market.Described intensity is determined by (through what revise) spectrum, wherein Int (S ₁→ S ₀) or Int (T ₁→ S ₀) represent the fluorescence or phosphoresence band intensity of quadraturing described fluorescence or phosphoresence band intensity can be determined by belonging to spectrophotometric program.Corresponding transition (band strength) can easily identify, because triplet state band (Triplett-Bande) is in the energy place lower than singlet state band and gets a promotion along with temperature reduces intensity.Here the solution (about 10 of the dilution in anaerobic is measured ^{– 2}molL ^{– 1}) in or performing by corresponding molecular film or on the film with corresponding molecular dopant.If adopt solution as sample, then desirably, use such solvent or solvent mixture, described solvent or solvent mixture form vitreum at low temperatures, as such as 2-methyltetrahydrofuran (2-Methyltetrahydrofuran), butyronitrile ₍or ethanol/carbinol mixture Butyronitril).If adopt film as sample, then use the matrix with obviously larger singlet state and triplet energies to be suitable as radiator molecule, such as, adopt PMMA (polymethylmethacrylate (Polymethylmethacrylat)).Described film can be applied by solution.

Straight slope Wei – Δ E (S ₁-T ₁)/k _b.At k _b=1.38010 ^-23jK ^-1=0.695cm ^-1k ^-1when, directly can determine energy difference.

To Δ E (S ₁-T ₁) estimation that value is simple and approximate also can carry out like this, that is, at low temperatures (such as when adopting cryostat under 77K or 4.2K), record fluorescence Spectra and phosphorescence spectrum.Δ E (S ₁-T ₁) at time close to the energy difference be equivalent between the high energy positive rise of fluorescence band or phosphoresence band.

Δ E (S ₁-T ₁) the another kind of defining method of value realizes by measuring to utilize surveying instrument common on market to measure to launch fall time.Here emission lifetime τ measures in such as 4.2K or the region such as between 20K and 300K by means of cryostat as the function of temperature.Use formula 1 and the emission lifetime τ (T of triplet state recorded at low temperatures ₁), formula 1 can be utilized to perform matching (Fit) to observed value, and obtain Δ E (S ₁-T ₁) value.(instruction: τ (T ₁) value is usually by the level ground (Plateau) that obtains being determined when marking and drawing observed value.If surface defines this level ground, then usually no longer need to be cooled to 4.2K).

Determine that validity or the triplet lifetime of Quantum geometrical phase can carry out as follows with experiment method:

The validity of Quantum geometrical phase and T ₁the substate I of state, the zero-field splitting (Nullfeldaufspaltung) of II, III are associated.Total zero-field splitting Δ E (III-I) is larger, in other words the energy spacing of triplet state substate III and I is larger, then the efficiency of Quantum geometrical phase is larger, and the radioactivity life-span of triplet state is shorter (see H.Yersin, A.F.Rausch, R.Czerwieniec, T.Hofbeck, T.Fischer, Coord.ChemRev.2011,255,2622).Zero-field splitting Δ E (III-I) is the parameter that can be obtained by test, and described parameter can directly be determined by high-resolution spectrum, or can determine fall time by measuring to launch.When using aforesaid method, measuring in the temperature range of 1.3K to 300K and launching fall time.The matching to observed value can be performed by means of following formula:

${\mathrm{\&tau;}}_{therm}=\frac{1+\exp (-\frac{\mathrm{\&Delta;}E(II-I)}{k_{B}T})+\exp (-\frac{\mathrm{\&Delta;}E(III-I)}{k_{B}T})+\exp (-\frac{\mathrm{\&Delta;}E(S_1-T_1)}{k_{B}T})}{\frac{1}{\mathrm{\&tau;}\left(I\right)}+\frac{1}{\mathrm{\&tau;}\left(II\right)}\exp (-\frac{\mathrm{\&Delta;}E(II-I)}{k_{B}T})+\frac{1}{\mathrm{\&tau;}\left(III\right)}\exp (-\frac{\mathrm{\&Delta;}E(III-I)}{k_{B}T})+\frac{1}{\mathrm{\&tau;}\left(S_1\right)}\exp (-\frac{\mathrm{\&Delta;}E(S_1-T_1)}{k_{B}T})}---\left(3\right)$

And obtain splitting parameter Δ E (II-I), Δ E (III-I) and its life-span τ (I), τ (II), the τ (III) of triplet state substate, and additionally obtain singlet state-triplet state division Δ E (S ₁-T ₁) and singlet lifetime.Value Δ E (S ₁-T ₁) relate to minimum triplet state substate I and S ₁the energy difference of state.An example of this processing mode is shown in the Fig. 7 for embodiment 2.According to the present invention, the value of zero-field splitting Δ E (III-I) is greater than 3cm ^-1, be preferably greater than 10cm ^-1, be particularly preferably greater than 20cm ^-1.

Triplet lifetime τ (T ₁) drawn by life-span τ (I), the τ (II) of triplet state substate, τ (III) according to equation (3a).For Δ E (II-I) <<k _bt and Δ E (III-I) <<k _bt, can determine τ (T according to equation (3a) by the life-span of each triplet state substate ₁)

$\mathrm{\&tau;}\left(T_1\right)=\frac{3}{\frac{1}{\mathrm{\&tau;}\left(I\right)}+\frac{1}{\mathrm{\&tau;}\left(II\right)}+\frac{1}{\mathrm{\&tau;}\left(III\right)}}---\left(3a\right)$

Can read triplet lifetime by level ground by test, described level ground forms (Fig. 7 seen below) when marking and drawing emission lifetime according to temperature in the scope of about 20K to 30K and the scope of about 80K to 100K.

The feature of preferred transition metal complex is to use Cu (I) central ion and/or Ag (I) central ion, wherein obtained complex compound be monokaryon, double-core or multinuclear, and lowest excited electricity substate has significant metal to ligand charge transfer characteristics, and wherein part is preferably multiple tooth cooperation.

In one form, the Local Symmetries in the position of the central ion of transition metal complex is subject to obvious destruction relative to tetrahedral symmetry.Consequently, be arranged in the region of the highest track boundary (HOMO, HOMO-1, HOMO-2 etc.) be occupied at the highest different d track, lowest excited electronics substate participates in these track boundaries.This characteristic causes the raising of Quantum geometrical phase between different states, and causes the increasing zero-field splitting of wishing according to the present invention thus and cause reducing radioactivity triplet state emission lifetime τ (T ₁).This target such as also can realize by using the complex compound only with the monokaryon of three-fold coordination.

In another form of implementation, the MLCT state of transition metal complex has the HOMO component be made up of d track significantly and the LUMO component be made up of the π * track of part, described d track (such as passes through two Cu (I) ions by multiple Cu (I) central ion displacement (delokalisiert), see embodiment 1), wherein, a part is bonded on Cu (I) central ion by it.Therefore enhance the effect of Quantum geometrical phase and shorten zero-field splitting and radioactive emission life-span τ (T ₁).

Accompanying drawing explanation

Fig. 1 illustrates energy level schematic diagram, for illustration of triplet state and singlet state results effect.τ (T ₁): triplet lifetime; τ (S ₁): singlet lifetime; τ _therm: average (thermalization (thermalisierte)) emission lifetime; ISC: intersystem crossing; Δ E (S ₁-T ₁): singlet state-triplet energies is poor.K _bit is Boltzmann constant.

Fig. 2 is Cu ₂i ₂(2-methylnaphthalene) (triphenylphosphine) ₂[Cu ₂i ₂(2-Methylnaphthyridin) (Triphenylphosphan) ₂] molecular structure (see embodiment 1A).

Fig. 3 is Cu ₂i ₂(2-methylnaphthalene) (triphenylphosphine) ₂track boundary (see embodiment 1A), HOMO (left side) and LUMO (right side).This accompanying drawing illustrates, obvious MLCT transition occurs between HOMO and LUMO

Fig. 4 is Cu ₂i ₂(2-trimethyl-naphthalene) (triphenylphosphine) ₂[Cu ₂i ₂(2-Trimethylnaphthyridin) (Triphenylphosphan) ₂] molecular structure (see embodiment 1B).

Fig. 5 is Cu ₂i ₂(2-trimethyl-naphthalene) (triphenylphosphine) ₂track boundary (see embodiment 1A), HOMO (left side) and LUMO (right side).This accompanying drawing illustrates, obvious MLCT transition occurs between HOMO and LUMO.

Fig. 6 is Cu ₆(L) ₆molecular structure, wherein symmetry operation (Symmetrieopteration) (i)=-x+1 ,-y+1 ,-z+1.

Fig. 6 a illustrates a part for asymmetric cell, for showing the bonding pattern of thiourea ligand.Described part is by a μ ²-S atom and a μ ¹-atom N cross-over connection Cu ₆an octahedral triangle side, in other words, two copper atoms of gore are by sulphur atom cross-over connection, and the 3rd copper atom is by the nitrogen atom bonding of identical ligands.

Fig. 7 illustrates the emission lifetime of the powdered sample of embodiment 2 and the curve of time correlation.

Embodiment

The present invention relates to and create and provide and identify new compound.The feature of this new compound is particularly in following characteristic: only have shorter radioactive emission life-span of several milliseconds, high emission quantum yield more than 50%, be less than 2000cm ^-1poor, the radioactivity triplet lifetime that is less than 100 μ s of singlet state-triplet energies, the transmitting component that is less than the radioactivity singlet lifetime of 500ns, the triplet state more than 3%.

Embodiment 1

Embodiment 1 illustrates the general chemical formula (formula I) for radiator according to the present invention:

X is I ^-, Br ^-, Cl ^-, NCS ^-, Ar-O ^-, Ar-S ^-or Ar-Se ^-, wherein Ar forms aryl or heteroaryl,

Q1 and Q2 is P or As independently of one another,

R1 to R6 is alkyl, aryl, heteroaryl or other functionalized alkyl, aryl, heteroaryl independently of one another,

A1 to A6 is C-R ' or N independently of one another, wherein R '=H, alkyl, aryl, heteroaryl or other functionalized alkyl, aryl, heteroaryl, Cl, Br, I, OH, OR ", SH, SR ", NH ₂, NHR ", NR " R " ', PR " R " ' R " ", COR ", CO ₂r ", CN, CONR ".R ", R " ' and R " " is alkyl, aryl or heteroaryl, and they may be functionalized further.Atom group (Atomgruppen) A1 to A6 can be interconnected by R ' functional group (Funktion), thus can form other ring (Zyklus).Side base R ' also can be connected with Phosphine ligands or cacodylic acid part (Arsanliganden) radicals R 1 to R6 by covalent linkage.

Formula I describes copper (I) complex compound, wherein at least one group be made up of A1 to A6 ≠ CH or group that at least one is made up of R1 to R6 have the phenyl of aliphatic chain or replacement, the such as ring system of m-, o-or p-tolyl or other aromatics or heteroaromatic.

First improve the complex compound solubility in organic solvent of formula I by these substituting groups (Substitution), and hence improve workability.In addition the substituent R ' be particularly preferred of group A1 and A6, because make complex compound harden and thereby reduce transmitting extinguishing process thus.By each side base R ' each other or further increase stability and the rigidity of the material of formula I with the connection of radicals R 1 to R6.In addition, by using (aliphatics of such as fluoridizing or the aromatic group) that attract electronics or (such as aliphatic chain, the dialkylamine etc.) group repelling electronics to determine the utilizing emitted light color of wishing.

The complex compound according to the present invention of formula I is at suitable Cu (I) salt (such as CuX, wherein X=Cl, Br or I) with the organic ligand of stoichiometry amount: synthesize in the reaction in inert gas atmosphere of phosphine or cacodylic acid Q1R1R2R3 and Q2R4R5R6 and the heteroaromatic ligands (being dissolved in organic solvent, such as, in acetonitrile) of being allocated by nitrogen.

Provide the example of the complex compound of formula I below:

Embodiment 1A

Cu ₂i ₂(2-methylnaphthalene) (triphenylphosphine) ₂chemical formula.

Affiliated molecular structure is shown in Figure 2.Adopt B3LYPDFT functional and SVP base group (for all atoms) to determine described molecular structure, wherein the internal electron of iodine is substituted by pseudo potential (Pseudopotenzial (ECP)).Composition optimizes utilizes Gaussian09 program to carry out.

Fig. 3 illustrates Cu ₂i ₂(2-methylnaphthalene) (triphenylphosphine) ₂affiliated track boundary, and HOMO (left side) and LUMO (right side) is shown.TD-DFT calculates (B3LYP/SVP+ECP) and draws minimum S ₀→ ³mXLCT and S ₀→ ¹the energy of MXLCT transition is 1.33eV and 1.35eV.Therefore energy difference Δ E (S ₁-T ₁) be about 0,02eV (≈ 160cm ^-1).The TD-DFT performed for this compound calculates to have shown clearly and realizes little Δ E (S ₁-T ₁) charge transfer transition needed for energy difference.

Embodiment 1B

Cu ₂i ₂(2-trimethyl-naphthalene) (triphenylphosphine) ₂chemical formula.

Affiliated molecular structure is shown in Figure 4.Described molecular structure adopts B3LYPDFT functional and SVP base group (for all atoms) to determine, wherein the internal electron of iodine is substituted by pseudo potential.Composition optimizes utilizes Gaussian09 program to carry out.

Fig. 5 illustrates Cu ₂i ₂(2-trimethyl-naphthalene) (triphenylphosphine) ₂affiliated track boundary, and HOMO (left side) and LUMO (right side) is shown.TD-DFT calculates (B3LYP/SVP+ECP) and draws minimum S ₀→ ³mXLCT and S ₀→ ¹the energy of MXLCT transition of electron is 1.49eV and 1.51eV.Therefore energy difference Δ E (S ₁-T ₁) be about 0.02eV (≈ 160cm ^-1).The TD-DFT performed for this compound calculates to have shown clearly and realizes little Δ E (S ₁-T ₁) charge transfer transition needed for energy difference.

Embodiment 2

Part synthesizes: L=Me – SO ₂– NH – C (S) – NH – Et

The synthesis of part is according to document (M. f.Geistmann, M.Schuster, Analyt.Chim.Acta2003,486,11-19) based on EtNCS and Me – SO ₂– NH ₂carry out in acetone.

Complex compound synthesizes: Cu ₆(L) ₆

This complex compound according to document (C.Holzer, Monatsheftef ü rChemie1994,125,1353-1364) by CuSO ₄manufacture in aqueous with the part of two equivalents.By formed throw out (Niederschlag) being dissolved in the DMF of heat and there is the throw out of MeOH (methyl alcohol) in purify.By crystallization by CHCl ₃pure six aggressiveness (Hexamer) are obtained in/MeOH.

The identity of compound confirms (Fig. 6,6a) by Single Crystal X-ray structural analysis.

Table 1:Cu ₆(L) ₆transmitting data.Radioactivity (k _r(300K)) and on-radiation (k _nr(300K)) value of speed adopts relational expression φ _pL=k _r/ (k _r+ k _nr)=k _rτ determines.

The curve of emission lifetime shown in Fig. 7 and temperature correlation.Solid line illustrates the matching according to equation 3.Obtain following match value: τ (I)=330 μ s, τ (II)=130 μ s, τ (III)=16 μ s, τ (S ₁)=210ns, Δ E (II-I)=3cm ^-1, Δ E (III-I)=13cm ^-1with Δ E (S ₁-T ₁)=600cm ^-1.Triplet lifetime τ (T is obtained according to equation 3a ₁)=41 μ s.This value calculated is close to the observed value τ (T equaled when T=77K ₁)=45 μ s.This meeting and show, at about 100cm well ^-1energy region in there are not other energy state and corresponding launch (uniquely) clearly and belong to T ₁state.The size delta E (III-I) of zero-field splitting clearly demonstrate that the importance of Quantum geometrical phase.When not having triplet state or three baryon states participate in the described effect of launching, under envrionment temperature (300K), calculating emission lifetime according to equation 3 is τ _therm=12 μ s, instead of the 8.5 μ s recorded.

Launch by triplet state the strength component at room temperature contributed in total emissive porwer to be quantized by following investigation.The total intensity I launched _gesamti (T is launched by triplet state in cumulative ground ₁) and singlet state transmitting I (S ₁) composition.I (T ₁) and I (S ₁) can be expressed by following formula:

I(i)＝α·k _r(i)·N(i)(4)

Wherein i=T ₁, S ₁.α represents rate constant.K _r(i)=Φ _pLi ()/τ (i) represents the radioactivity deactivation rate (radiativeDesaktivierungsrate) of state i, and N (i) represents the occupy-place number (Besetzungszahl) of state i.Occupy-place number meets ANALOGY OF BOLTZMANN DISTRIBUTION in thermalization system.Therefore equation 4 can be rewritten into following form:

$I\left(i\right)=\mathrm{\&alpha;}\&CenterDot;\frac{{\mathrm{\&Phi;}}_{PL}\left(i\right)}{\mathrm{\&tau;}\left(i\right)}\&CenterDot;\frac{N}{Z\left(T\right)}\&CenterDot;g\left(i\right)\&CenterDot;\exp (-\frac{\mathrm{\&Delta;}E(i-T_1)}{k_{B}T})---\left(5\right)$

G (i) represents degeneracy (Entartungsgrad) (g (S of state i ₁)=1, g (T ₁)=3), N represents the sum of the radiator complex compound excited, and Z (T) represents state summation.In addition k _ri () uses Φ _pLi ()/τ (i) substitutes.Triplet state is launched the per-cent accounting for total intensity and can be represented by following formula now:

$\frac{I\left(T_1\right)}{I_{gesamt}}=\frac{I\left(T_1\right)}{I\left(T_1\right)+I\left(S_1\right)}=\frac{1}{1+\frac{{\mathrm{\&Phi;}}_{PL}\left(S_1\right)\&CenterDot;\mathrm{\&tau;}\left(T_1\right)}{3\&CenterDot;{\mathrm{\&Phi;}}_{PL}\left(T_1\right)\&CenterDot;\mathrm{\&tau;}\left(S_1\right)}\&CenterDot;\exp (-\frac{\mathrm{\&Delta;}E(S_1-T_1)}{k_{B}T})}---\left(6\right)$

As supposition Photoluminescent quantum yield Φ _pL(S ₁) and Φ _pL(T ₁) when having an identical value, simplify equation 6 further as follows:

$\frac{I\left(T_1\right)}{I_{gesamt}}=\frac{1}{1+\frac{\mathrm{\&tau;}\left(T_1\right)}{3\&CenterDot;\mathrm{\&tau;}\left(S_1\right)}\&CenterDot;\exp (-\frac{\mathrm{\&Delta;}E(S_1-T_1)}{k_{B}T})}---\left(7\right)$

By means of equation 7 and the value determined by the matching of Fig. 7, for embodiment 2, can provide the strength component per-cent that triplet state launches is 20%, and show that total emission lifetime shortens to 8.5 μ s thus.

Claims (19)

1. the transition metal complex of luminescence, has

-minimum triplet state (T ₁) transmitting, and

-higher than minimum triplet state (T ₁) singlet state (S ₁) transmitting,

Wherein, occupying of these states is in thermal equilibrium, and

Described transition metal complex preferably at least 3% emissive porwer obtained by described triplet state or described singlet state.

2. transition metal complex according to claim 1, wherein, described transition metal complex is at minimum triplet state (T ₁) and the singlet state (S that is located thereon ₁) between have and be less than 2000cm ^-1, be preferably less than 1000cm ^-1, be particularly preferably less than 300cm ^-1energy difference.

3. transition metal complex according to claim 1 and 2, wherein, the triplet state that described transition metal complex is minimum has the zero-field splitting of substate I, II, III, and the energy difference Δ E (III-I) between substate III and I is greater than 3cm ^-1, be preferably greater than 10cm ^-1, and be particularly preferably greater than 20cm ^-1.

4. according to the transition metal complex in claim 1-3 described in any one, wherein, described transition metal complex has and is less than 100 μ s, is preferably less than 50 μ s, is more preferably less than 20 μ s and is particularly preferably less than the minimum triplet state (T of 5 μ s ₁) the radioactivity life-span.

5. according to the transition metal complex in claim 1-4 described in any one, wherein, described transition metal complex has Cu (I) and/or Ag (I) central ion.

6. according to the transition metal complex in claim 1-5 described in any one, wherein, described transition metal complex has at least one polydentate ligand, and described polydentate ligand is engaged on the central ion of transition metal complex.

7. according to the transition metal complex in claim 1-6 described in any one, wherein, described transition metal complex is the complex compound of monokaryon, double-core or multinuclear, and the coordination wherein around metal center is triple or multiple.

8. according to the transition metal complex in claim 1-7 described in any one, wherein, described transition metal complex has the charge transfer transition of metal to part, and wherein said MLCT state has:

-there is the HOMO component of significant d orbital characteristics, described d track is realized by multiple central ion in the complex compound of double-core or multinuclear; And

-LUMO component, it is made up of the π * track of part substantially, and described part is bonded on multiple central ion in the complex compound of double-core or multinuclear.

9. according to the application of the transition metal complex in claim 1-8 described in any one in photoelectron device, especially for utilizing emitted light.

10. application according to claim 9, wherein, the emission layer in photoelectron device has the transition metal complex according to any one in claim 1-5, and the concentration of transition metal complex described in emission layer is 2 % by weight to 100 % by weight.

11. photoelectron devices, this photoelectron device has according to the transition metal complex in claim 1-8 described in any one.

12. devices according to claim 11, wherein, the ratio of transition metal complex in emission layer or absorption layer is 2-100 % by weight about the gross weight of emission layer, is preferably 20-80 % by weight.

13. devices according to claim 11 or 12, wherein, described photoelectron device is selected from following group, this group comprises: Organic Light Emitting Diode (OLED), light-emitting electrochemical cell (lightemittingelectrochemicalcell, LEEC), OLED sensor does not particularly have sensor, organic solar batteries (organic solar batteries (organicsolarcells), the OSCs of gas and the steam outwards shielded hermetically; Organic photovoltaic (organicphotovoltaics), OPVs), organic field effect tube, organic laser, organic diode, organic photosensitive diode and for ultraviolet being converted to visible ray or being used for the light of shorter wavelength to convert to " lower conversion " system of the light of longer wavelength.

14. for the manufacture of the method for photoelectron device, and wherein use according to the transition metal complex in claim 1-8 described in any one, described metal complex is particularly applied on solid carrier by colloidal suspension or by distillation to wet-chemical.

15., for generation of the method for light determining wavelength, comprise the step provided according to the transition metal complex in claim 1-8 described in any one.

16. according to the method for the transition metal complex in claim 1-8 described in any one, comprise execution for selecting:

-from the beginning (ab-initio) molecular computing, or

The temperature dependency of-measurement fluorescence intensity and phosphorescence intensity, or

The temperature dependency of-measurement emission lifetime.

17. methods according to claim 16, wherein select according to the transition metal complex in claim 2-8 described in any one, and described transition metal complex is at lowest excited singlet state (S ₁) and the triplet state (T that is positioned under it ₁) have and be less than 2000cm ^-1Δ E (S ₁-T ₁) value, it is characterized in that,

-by from the beginning (ab-initio) molecular computing, or

-by measuring the temperature dependency of fluorescence intensity and phosphorescence intensity, or

-determine Δ E (S by the temperature dependency measuring emission lifetime ₁-T ₁) value, and

-determine Δ E (S ₁-T ₁) value 2000cm ^-1transition metal complex.

18. methods according to claim 16, select according to the transition metal complex in claim 3-8 described in any one, and described transition metal complex has in the triplet state of minimum energy and is greater than 3cm ^-1, be preferably greater than 10cm ^-1, and be particularly preferably greater than 20cm ^-1substate I, II, III zero-field splitting Δ E (III-I), it is characterized in that,

-by from the beginning (ab-initio) molecular computing, or

-by measuring the temperature dependency of emission lifetime, or

-by the high-resolution transmitting about between 1.3K to 20K or excite spectrometer measurement to determine Δ E (III-I) value.

19. for selecting the method according to the transition metal complex in claim 4-8 described in any one, the triplet state (T of the minimum energy of described transition metal complex ₁) the radioactivity life-span be less than 100 μ s, be preferably less than 50 μ s, be more preferably less than 20 μ s and be particularly preferably less than 5 μ s, and being particularly preferably less than 5 μ s, it is characterized in that,

-by from the beginning molecular computing or

-by the area inner measuring emission lifetime on formed level ground and launch the value that the temperature dependency of yield determines radioactive emission fall time of triplet state.