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This study employs density functional theory (DFT) and time‐dependent density functional theory (TD‐DFT) to investigate a series of cyclometallated Ir(III) complexes for their application as OLED light‐emitting materials, including (dtp)2Ir(dpm), (mmpyp)2Ir(dpm), (dtp)2Ir(tpip), (mmpyp)2Ir(tpip), (dtp)2Ir(pic), and (mmpyp)2Ir(pic). Their geometries, frontier molecular orbital properties, ionization potential, electron affinity, absorption and emission spectra, and spin‐orbit coupling properties have been analyzed respectively. Through comparison, we have identified complexes with reduced efficiency roll‐off and enhanced kISC. [ABSTRACT FROM AUTHOR]

Organic light-emitting diodes (OLEDs) have been widely used in various fields such as sensors. In this article, we designed six novel heterocyclic Ir(III) complexes: (CFM)2Ir(acac) (named 1 in this paper), (TTIQ)2Ir(acac) (named 2), (CFM)2Ir(tmd) (named 3), (TTIQ)2Ir(tmd) (named 4), (CFM)2Ir(pic) (named 5) and (TTIQ)2Ir(pic) (named 6). The six iridium (III) complexes were calculated using Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT). We studied the bands of the lowest-lying absorptions and lowest energy emissions of complexes 1–6. In addition, we also explored their spectral properties, frontier Molecular Orbital theory(FMO) and spin-orbital coupling value(SOC). Where acac is represented as pentane-2, 4-dione; tmd as 2,2,6,6-tetramethylheptane-3,5-dione; pic as pyridine-2-carboxylate; TTIQ as 1- { thieno[3,2-b]thiophen-2-yl } isoquinoline; CFM as 2-(4-fluorobrobenyl)-4-methylpyridine. A series of heteroleptic cyclometalated Ir (III) complexes, which are used for OLED application, were investigated by DFT and TD-DFT method. The frontier molecular orbital character and charge transfer character shown that they have the advantages of low efficiency roll-off properties, which is a 'stumbling block' in the process of OLED solid-lighting's development. Namely, means the materials will play an important role in the journey development of OLED. [ABSTRACT FROM AUTHOR]

In this paper, several Ir (III) complexes with transition metal as the central atom formed by the corresponding combination of two main ligands and three auxiliary ligands have been studied theoretically. The electronic structure, frontier molecular orbital, and spin orbit coupling data are used to analyze its application value in light emitting devices. The density functional theory is used to study (tbi)2Ir(bpp), (tbi‐c)2Ir(bpp), (tbi)2Ir(dbm), (tbi‐c)2Ir(dbm), (tbi)2Ir(pic), and (tbi‐c)2Ir(pic). bpp = (2Z)‐3‐hydroxy‐13‐diphenylprop‐2‐en‐1‐one; dbm = 1,3‐di‐phenyl‐1, 3‐propanedione; pic = picolinate. [ABSTRACT FROM AUTHOR]

A series of heteroleptic cyclometalated Ir(III) complexes for OLEDs application have been investigated theoretically to explore their electronic structures and spectroscopic properties. The geometries, electronic structures, lowest‐lying singlet absorptions, and triplet emissions of (pdbi)2Ir(acac), (F‐pdbi)2Ir(acac), (pdbi)2Ir(dpis), (F‐pdbi)2Ir(dpis), (pdbi)2Ir(tpip), and (F‐pdbi)2Ir(tpip) were investigated with density function theory (DFT) and time‐dependent density functional theory (TD‐DFT), where pdbi denotes 1‐(4‐fluorophenyl)‐5‐methyl‐3‐phenyl‐2,3‐dihydro‐1H‐1,3‐benzodiazole, acac denotes acetylacetonate, dpis denotes diphenylimidodisilicate, and tpip denotes tetraphenylimido‐diphosphinate. In addition, we analyzed the spin‐orbit coupling constant of these six complexes, and the results showed that the six complexes have a high ability of interlinear scampering. We hope this research can serve as a reference for practical experimental synthesis aspects. [ABSTRACT FROM AUTHOR]

A series of heteroleptic cyclometalated Ir (III) complexes, which are used for OLED application, were investigated by DFT and TD-DFT method. The frontier molecular orbital character and charge transfer character shown that they have the advantages of low efficiency roll-off properties, which is a "stumbling block" in the process of OLED solid-lighting's development. Namely, means the materials will play an important role in the journey development of OLED. [Display omitted] • Cyclometalated iridium (III) complexes have received special attention as dopants for harvesting the otherwise nonemissive triplet states formed in OLEDs, but now, most of them cannot satisfy to be used for the applications, especially for Bright blue and Near-infrared , since that a fast reduction in efficiency known as roll-off, however, occurs when the drive current increases, this leads to a much lower luminance and more power consumption. • Thus in this paper, in order to find a kind of Bright blue and Near-infrared OLED materials with low efficiency roll-off properties, we theoretical design and investigate a series of Iridium complexes. • The geometries, electronic structures, the lowest-lying singlet absorptions, triplet emissions properties and the application value for organic light emitting devices were all analyzed by theory in this article. A series metal iridium complexes were calculated using the method of DFT and TD-DFT under Gaussian 09 software. H atoms on the N counter in 2-(4-fluorophenyl)pyridine were replaced with methyl and nitro groups, respectively, to obtain two main ligands CFM(2-(4-fluorobrobenyl)-4-methylpyridine) and CFN(2-(4-fluorobrobenyl)-4-nitropyridine), then we obtained six complexes: (CFM) 2 Ir(acac), (CFM) 2 Ir(tpip), (CFM) 3 Ir, (CFN) 2 Ir(acac), (CFN) 2 Ir(tpip) and (CFN) 3 Ir, Where acac is represented as pentane-2, 4-dione, tpip as tetraphenylimido-diphosphinate. The electronic structure, the lowest singlet absorption, the triple excited states as well as the emission spectrum are also theoretically studied. [ABSTRACT FROM AUTHOR]