Triplet Energy Level Research Articles

Magnetic field effects on the quenching of triplet excitons in exciplex-based organic light emitting diodes

Triplet excited states in exciplex-based organic light emitting diodes (OLEDs) can be wasted by transferring their energy to the host material in a system with smaller triplet energy levels.

A highly sensitive luminescent metal–organic framework thermometer for physiological temperature sensing

Thermal sensing and imaging in the physiological temperature range are of great importance for studying physiological processes and treating diseases. Metal–organic frameworks (MOFs) exhibit great promise for developing luminescent thermometers due to their remarkable structural diversities and tunable luminescence properties. Here, we synthesized a series of luminescent mixed-lanthanide MOFs, EuxTb1-xBPT (x = 0.019, 0.058, 0.106; H3BPT = biphenyl-3,4′,5-tricarboxylate acid) and adopted powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) to characterize the resulting products. The temperature-dependent photoluminescence emission spectra were recorded to investigate their potential applications in physiological temperature readout. It is found that the intensity ratio of Tb3+ to Eu3+ is linearly correlated with temperature and the relative sensitivity is higher than 1.5%/°C over the entire physiological temperature range. Furthermore, the temperature-dependent luminescence color emission allows for visual colorimetric temperature measurements. Luminescence lifetime testing and triplet energy level measurement were further conducted to study the mechanism.

Derivatives of carbazole and chloropyridine exhibiting aggregation induced emission enhancement and deep-blue delayed fluorescence

New carbazole-chloropyridine donor-acceptor compounds were obtained with the yields of 49–77% by a one-step catalyst-free nucleophilic substitution reaction of pentachloropyridine and carbazole. The structures of the compounds were confirmed by 1H, 13C NMR and IR spectroscopy and mass spectrometry. X-ray single crystal diffraction analysis was performed for monosubstituted derivative of pentachloropyridine. Computational studies revealed high theoretic triplet energy levels with small singlet-triplet energy gaps. Electrochemical, thermal and photophysical properties of the compounds were studied. The solid films of the compounds exhibited fluorescence in the range of 435–465 nm. Disubstituted and trisubstituted derivatives formed molecular glasses with glass transition temperatures of 93 °C and 134 °C, respectively. Singlet-triplet energy splitting of the obtained compounds were in the range from 0.06 eV to 0.31 eV depending on the number of attached carbazolyl moieties. Triplet energy levels of the compounds were estimated to be in the range from 3.05 eV to 3.08 eV. The mono-substituted derivative exhibited aggregation induced emission enhancement and thermally-activated delayed fluorescence. It exhibited deep blue emission with chromaticity coordinates of (0.17, 0.13) and 16% photoluminescence quantum yield in the solid state.

Organic planar pn heterojunction light-emitting diodes: Materials and devices

Organic light-emitting diodes (OLEDs) have been widely applicable in the flat-panel display products, such as mobile phones and television. They also possess more outstanding application advantages in the area of wearable display products in the future and have a great potential to serve as a key competitor in the next-generation solid-state lighting technology. For the commercial OLED products, phosphorescent materials that contain the rare metals are essential. This is because that phosphorescent OLEDs can give more efficient radiation, as the result of harvesting both singlet and triplet excitons for radiative utilization, in contrast to traditional fluorescent emitters. However, because of the limited resources of the rare metals, e.g., indium, on the earth, the phosphorescent materials are rather expensive, and their sustainable supply are also questionable. Besides, the long-term stability of blue phosphorescent emitters are also challenging. To further lower the fabrication cost of materials and devices, numerous research efforts have been devoted to developing rare-metal-free, purely organic light-emitting materials, which could be more low-cost and still exhibit excellent electroluminescence performances. In this review, we firstly introduce the evolution of OLED materials and devices. The OLED materials could be roughly classified into three generations. For the 1st generation traditional fluorescent emitters, three quarters of electro-generated excitons are wasted as heat release, due to the spin forbidden rule of triplets. This suggests that the OLEDs employing traditional fluorescent emitters could only achieve a maximum internal quantum efficiency of 25%. For the 2nd generation phosphorescent emitters, the spin orbital coupling due to heavy atom effect results in the mixing of singlet and triplet energy levels, and make triplet radiative transition feasible. Thereby, phosphorescent OLEDs can obtain a maximum internal quantum efficiency close to 100%. Recently, the 3rd generation hyperfluorescence emitters with the thermally activated delayed fluorescence (TADF) character could also make the devices thereof give an internal quantum efficiency close to 100%. This paves a road to realize low-cost and high-performance OLEDs based on purely organic semiconductors. We also outline the evolution of the OLED device configuration. For single-, double- and multi-layer device configuration of conventional OLEDs, their performances are mainly dependent on the emission layer (EML). The current methodology to develop high-performance OLEDs is to maximize the light emission ability of EML. Based on the understanding of the excitonic property of organic semiconductors, we show that efficient EML-free planar pn heterojunction light-emitting diodes (pn-OLEDs) should be realizable, given that the planar heterojunction property is well modulated. This indicates a way to directly construct efficient fluorescent OLEDs without an EML from the perspective of planar heterojunction composed of p type and n type charge transport materials. As following, the progress of OLEDs based on the layer-to-layer charge transfer mechanism using purely organic semiconductors is introduced. Main discussion focuses on pn-OLEDs, including that how this concept was proposed and the progress of relevant materials and devices. We also discuss the challenges of developing high performance pn-OLEDs and their potential applications in other optoelectronic areas, such as organic light-emitting transistors and electrically-pumped organic laser.

Tuning the photophysical properties of heteroleptic Ir(III) complexes through ancillary ligand substitution: Experimental and theoretical investigation

A series of new phosphorescent heteroleptic Iridium(III) complexes with 2-phenylpyridine, acetylacetone and 2-picolinic acid as ancillary ligands have been designed and synthesized. The photophysical and electrochemical properties have been investigated experimentally and theoretically. The UV–vis absorption and photoluminescence (PL) emission spectra of the complexes were carried out in solution as well as thin film. The PL study indicates that the Iridium complexes show broadband emission ranging from green to yellowish-green in solution and greenish-yellow to yellow emission in PMMA films with appropriate CIE color gamut. The PLQY of the complexes were found to be in the range of 0.12–0.29. Singlet and triplet energy levels were calculated by using time dependent DFT (TD-DFT) calculations. The excited triplet energy was estimated and correlated to structural and energetic characteristics of the reported host materials. Further, investigations have been performed to explore the optical, electronic, charge transport, and stability properties of Ir(III) complexes as charge transport and emissive materials for organic light emitting devices (OLEDs). Furthermore, all the complexes are promising luminescent and its hole transporting performance is more favorable than electron transport performances. According to theoretical calculations, it is clearly indicating that, Ben-Ir-acac complex is a more potential emitter for OLED applications.

The Role of Charge Balance and Excited State Levels on Device Performance of Exciplex-based Phosphorescent Organic Light Emitting Diodes

The design of novel exciplex-forming co-host materials provides new opportunities to achieve high device performance of organic light emitting diodes (OLEDs), including high efficiency, low driving voltage and low efficiency roll-off. Here, we report a comprehensive study of exciplex-forming co-host system in OLEDs including the change of co-host materials, mixing composition of exciplex in the device to improve the performance. We investigate various exciplex systems using 5-(3–4,6-diphenyl-1,3,5-triazin-2-yl)phenyl-3,9-diphenyl-9H-carbazole, 5-(3–4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9-phenyl-9H-3,9′-bicarbazole, and 2-(3-(6,9-diphenyl-9H-carbazol-4-yl)phenyl)-4-phenylbenzo[4,5]thieno[3,2-d]pyrimidine, as electron transporting (ET: electron acceptor) hosts and 9,9′-dipenyl-9H, 9′H-3,3′-bicarbazole and 9-([1,1′-biphenyl]-4-yl)-9′-phenyl-9H,9′H-3,3′-bicarbazole as hole transporting (HT: electron donor) hosts. As a result, a very high current efficiency of 105.1 cd/A at 103 cd/m2 and an extremely long device lifetime of 739 hrs (t95: time after 5% decrease of luminance) are achieved which is one of the best performance in OLEDs. Systematic approach, controlling mixing ratio of HT to ET host materials is suggested to select the component of two host system using energy band matching and charge balance optimization method. Furthermore, our analysis on exciton stability also reveal that lifetime of OLEDs have close relationship with two parameters; singlet energy level difference of HT and ET host and difference of singlet and triplet energy level in exciplex.

Two spiro[fluorene-9,8′-indolo[3,2,1-de]acridine] derivatives as host materials for green phosphorescent organic light-emitting diodes

Two host materials based on spiro[fluorene-9,8′-indolo[3,2,1-de]acridine] derivatives were designed and synthesized by introducing the benzofuran/benzothiophene unit to the spiro [fluorene-9,8′-indolo[3,2,1-de]acridine] unit. The two host materials exhibited high triplet energy level (>2.65eV) and the benzofuran-substituted derivative presented suitable glass transition temperature (>130°C). Their electrochemical and photo-physical properties were also determined. The green phosphorescent organic light-emitting diodes based on the two host materials obtained electroluminescence performances with external quantum efficiencies of 14.3±0.1% and 11.9±0.1%, respectively.

Novel carbazole/indole/thiazole-based host materials with high thermal stability for efficient phosphorescent organic light-emitting diodes

Two host materials TIC1 (N-linked carbazole) and TIC2 (C-3-linked carbazole) via changing the substitution position of carbazole, indole and thiazole moieties are reported. Their structural and physical properties were fully characterized. The thermal analysis demonstrated that both TIC1 and TIC2 are thermally stable. The triplet energy levels of TIC1 and TIC2 were determined to be 2.54 and 2.58 eV, respectively. Green and blue OLEDs with TIC1 and TIC2 acting as host materials were fabricated to investigate their performances in PHOLED. Both green and blue PHOLEDs based on TIC2 show the best performance with the maximum current efficiency and maximum power efficiency of 60.0 cd/A and 48.0 lm/W (for green), 18.4 cd/A and 15.2 lm/W (for blue), respectively. The characteristic measurements of OLED devices reveal that both TIC1 and TIC2 are promising host materials for practical application. By comparing with the commercial host material of 4,4′-bis(carbazol-9-yl)biphenyl (CBP) and N,N-dicarbazoyl-3,5-benzene (mCP), the power efficiency of green and blue PHOLED was enhanced by 55.3% and 245%, respectively.

Bipolar Host Materials Based on 1,3,5‐Triazine Derivative for Green Phosphorescent Organic Light‐emitting Diode

We designed and synthesized new bipolar host materials 2–4, through microwave‐assisted Suzuki‐coupling reaction with 1,3,5‐triazine unit and carbazole/fluorene group. The photophysical and thermal properties of the synthesized 1,3,5‐triazine derivatives 2–4 were investigated by ultraviolet–visible (UV–vis) spectrometer, spectrofluorometer, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The 1,3,5‐triazine derivatives 2–4 have suitable energy bandgap (Eg = 3.15–3.35 eV) and high triplet energy level (ET, 2.63–2.87 eV) for phosphorescent green host. Device performance of 2–4 materials shows that maximum luminescence efficiency (LE) and external quantum efficiency (EQE) of green device A–C were 29.25, 49.67, and 48.74 cd/A and 8.68, 14.52, and 14.30%, respectively.

Theoretical Investigations of the Spiro‐Annulated Triphenylamine/ N‐Phenylcarbazole‐Based Ambipolar Host Materials for OLEDs

AbstractA series of spiro‐annulated triphenylamine/N‐phenylcarbazole derivatives as ambipolar host molecules have been designed by linking different electron acceptors (i. e., diphenylphosphine, phenylsulfone, triphenylsilane and diphenylborane). To reveal their electronic structures, optoelectronic properties and structure‐property relationships of the host materials, a throughout investigation was implied using density functional theory (DFT) and time‐dependent density functional theory (TDDFT) calculations. Results show that the triplet energy (ET), HOMO and LUMO energy levels, as well as some other properties i. e. ionization potentials (IPs), electron affinities (EAs), reorganization energies (λ) can be tuned by chemical modifications of different electron acceptors. The host‐guest models have also been built to investigate the match of the hosts and the reference guests. Comprehensively considering these indexes, the potential performance of 10‐phenyl‐2′‐(phenylsulfonyl)‐10H‐spiro[acridine‐9, 9′‐fluorene] (SOSTF) is a big leap in comparison with experimental host material diphenyl(10‐phenyl‐10H‐spiro[acridine‐9, 9′‐fluoren]‐2′‐yl)phosphine oxide (POSTF). It has been proved that a spiro‐annulated structure can be modified in constructing high ET host material for blue phosphorescent organic light‐emitting diodes.

PH-Responsive Low-Power Upconversion Based on Sandwichlike Palladiumphthalocyanine and Rhodamine B

Sandwhichlike palladiumphthalocyanine was found to possess highly efficient NIR triplet sensibilization with an increasing of ligand number, due to the triplet energy level (ET) enhancing and the triplet lifetime (3τ0) prolonging and resulting in efficient triplet–triplet energy transfer (TTT). Also, rhodamine B (RhB) was found to act as reactive triplet acceptor that emits red-to-yellow upconversion when doped with sandwhichlike complex. By tuning pH value, the three-layered phthalocyanine/RhB system presents so far the highest red-to-yellow upconversion efficiency (ΦUC) as large as 10.5% (λex = 655 nm, 1W·cm–2), which has provided a simple approach to develop not only the new-type highly efficient NIR sensitizers but also the TTA-UC supported pH response applied in biomedicine.

Isomeric N‐Linked Benzoimidazole Containing New Electron Acceptors for Exciplex Forming Hosts in Highly Efficient Blue Phosphorescent OLEDs

Three benzoimidazole containing new electron‐accepting materials of 1,3,5‐tris(2‐(pyridin‐2‐yl)‐1H‐benzo[d]imidazol‐1‐yl)benzene (i TPyBIB), 1,1′,1′′‐(pyridine‐2,4,6‐triyl)tris(2‐phenyl‐1H‐benzo[d]imidazole) (i TPBIPy), and 1,1′,1′′‐(pyridine‐2,4,6‐triyl)tris(2‐(pyridin‐2‐yl)‐1H‐benzo[d]imidazole) (i TPyBIPy) are designed and synthesized. Compared to the commercial electron‐transport 2,2,2‐(1,3,5‐phenylene)‐tris(1‐phenyl‐1H‐benzimidazole) (TPBI) with the C‐atom in benzoimidazole linked to the central phenyl ring, the introduction of isomeric N‐linkage to the central phenyl or pyridine ring in three compounds remarkably simplifies the synthesis to a one‐step CN coupling reaction. iTPyBIB, iTPBIPy, and iTPyBIPy exhibit comparable highest occupied molecular orbital (≈6.0 eV) and lowest unoccupied molecular orbital (≈2.5 eV) energy levels, similar triplet energy levels of ≈2.65 eV with TPBI, whereas reduced electron‐transport properties. All materials can be applied as electron acceptors to form universal exciplex with general hole‐transport electron donors, such as N,N′‐dicarbazolyl‐3,5‐benzene (mCP), 4,4′,4′′‐tris(N‐carbazolyl)‐triphenylamine (TCTA), and 1,1‐bis[4‐[N,N‐di(p‐tolyl)‐amino]phenyl]cyclohexane (TAPC) in the blended films with 1:1 molar ratio. A maximum external quantum efficiency of 17.0%, 19.3%, and 13.4% is achieved in mCP, mCP:iTPBIPy, and mCP:TPBI hosted blue phosphorescent organic light‐emitting diodes, respectively, indicating the superior electron‐acceptor property of the N‐linked iTPBIPy for exciplex forming cohost.

High Triplet Energy Level Achieved by Tuning the Arrangement of Building Blocks in Phosphorescent Polymer Backbones for Furnishing High Electroluminescent Performances in Both Blue and White Organic Light-Emitting Devices.

A high triplet energy level (ET) of ca. 2.83 eV has been achieved in a novel polymer backbone through tuning the arrangement of two kinds of building blocks, showing enhanced hole injection/transporting capacity. Based on this new polymer backbone with high ET, both blue and white phosphorescent polymers were successfully developed with a trade-off between high ET and enhanced charge-carrier transporting ability. In addition, their photophysical features, electrochemical behaviors, and electroluminescent (EL) properties have been characterized in detail. Benefitting from the advantages associated with the novel polymer backbone, the blue phosphorescent polymers show top-ranking EL performances with a maximum luminance efficiency (ηL) of 15.22 cd A-1, corresponding to a power efficiency (ηP) of 12.64 lm W-1, and external quantum efficiency (ηext) of 6.22% and the stable Commission Internationale de L'Eclairage (CIE) coordinates of (0.19, 0.38). Furthermore, blue-orange (B-O) complementary-colored white phosphorescent polymers based on this novel polymer backbone were also obtained showing encouraging EL efficiencies of 12.34 cd A-1, 9.59 lm W-1, and 4.10% in the optimized WOLED together with exceptionally stable CIE coordinates of (Δx = 0.014, Δy = 0.010) in a wide driving voltage range from 4 to 16 V. All of these attractive EL results achieved by these novel phosphorescent polymers show the great potential of this new polymer backbone in developing highly efficient phosphorescent polymers.

Thermally stable bipolar host materials for high efficiency phosphorescent green and blue organic light-emitting diodes

Two bipolar host materials H1 (N-linked carbazole) and H2 (C-3-linked carbazole) via changing the substitution position of triazine and carbazole moieties are reported. Their structural and physical properties were fully characterized. The thermal analysis demonstrated that both H1 and H2 are of high thermal stability. The triplet energy levels of H1 and H2 were determined to be 2.64 and 2.7 eV, respectively. Both green and blue OLEDs with H1 and H2 acting as host materials were fabricated to investigate their performances in PHOLED. The green PHOLED based on H1 exhibits the best performance with the maximum current efficiency, maximum power efficiency and maximum brightness of 51.7 cd/A, 37.8 lm/W and 132800 cd/m2, respectively, while the blue PHOLED based on H2 shows the best performance with the maximum current efficiency, maximum power efficiency and maximum brightness of 21.6 cd/A, 17.2 lm/W and 16640 cd/m2, respectively. The characteristic measurements of OLED devices reveal that both H1 and H2 are promising host materials for practical application. By comparing the commercial host materials of 4,4’-bis(carbazol-9-yl)biphenyl (CBP) and N,N-dicarbazoyl-3,5-benzene (mCP), the power efficiencies of green and blue PHOLED were boosted by 22.3% and 75.5%, respectively.

Novel Bipolar Indole-Based Solution-Processed Host Material for Efficient Green and Red Phosphorescent OLEDs.

A new bipolar host material 2-(2'-(5-(dibenzo[b,d]furan-4-yl)-1H-indol-1-yl)-1,1'-biphenyl]-4-yl)-1-phenyl-1H-benzo[d]imidazole (INDY) has been designed and synthesized for solution-processed PHOLEDs. A hole-transporting indole conjugated dibenzofuran scaffold and an electron-transporting benzimidazole unit were orthogonally connected with incorporation of a 2,4'-biphenyl bridge, which endows a balanced bipolar charge transfer distribution and appropriate triplet energy level (>2.6 eV). The twisted conformation of INDY also ensures good thermal/morphological stability with high Tg (148 °C). The solution-processed green PHOLEDs achieved great device efficiencies with 27.33 cd/A and 12.26 lm/W at 7 V. Meanwhile, the red solution-processed PHOLEDs gained excellent performance with the maximum efficiencies of 17.20 cd/A, 9.82 lm/W, and 12.61%. In addition, all of the red devices presented excellent color stability with the same CIE coordinate as (0.65, 0.35) under varying dopant contents and operating voltages.

Carbazolyl-substituted quinazolinones as high-triplet-energy materials for phosphorescent organic light emitting diodes

A series of carbazolyl-substituted quinazolinones were designed and synthesized by the Pd-catalyzed Buchwald-Hartwig, Suzuki and Heck cross-coupling reactions. Their optical, photophysical, thermal, electrochemical, and electroluminescent properties were investigated. The characterization of the synthesized compounds was carried out using experimental and theoretical methods. The determined geometries of the compounds lead to the HOMO distribution on the quinazolinone moiety and the different donor substituents. The synthesized compounds form glasses with the glass transition temperatures ranging from 97 to 159 °C. Their solutions in tetrahydrofuran absorb electromagnetic radiation in the range of 210–420 nm and emit in the range of 350–600 nm. The Stokes shifts recorded for the dilute solutions of compounds ranged from 48 to 134 nm, while those observed for the solid films were similarly in the range of 46–113 nm. The highest fluorescence quantum yield of 44.3% was recorded for the solution of 3-(9-ethyl-9H-carbazol-3-yl)-5-((E)-2-(9-ethyl-9H-carbazol-3-yl)ethenyl)-2-methylquinazolin-4(3H)-one. The triplet energy levels established for the dilute solutions of the compounds from their phosphorescence spectra at 77 K were found to be in the range of 2.55–2.99 eV. The ionization potentials of the synthesized compounds established by photoelectron emission technique in air ranged from 5.35 to 5.66 eV. The electrochemical properties of the derivatives were studied by cyclic voltammetry. All the studied compounds showed irreversible oxidation and no reduction waves. Their repeated cyclic voltammetry scans displayed increasing changes in the cyclic voltammetry traces, proving that a series of electro-polymerization reactions of the radical cations occurred. Time-of-flight hole drift mobility of the solid layer of 5-(bis(4-tert-butyldiphenyl)amino)-3-(9-ethyl-9H-carbazol-3-yl)-2-methylquinazolin-4(3H)-one reached 1.1 × 10−3 cm2/Vs at an electric field of 8.1 × 105 V/cm. This compound was tested as a host in the green and blue phosphorescent organic light emitting diodes achieving maximum external quantum efficiencies of ca. 7.1 and 6.9%, respectively.

Inelastic collisions of ultracold triplet Rb2 molecules in the rovibrational ground state

Exploring and controlling inelastic and reactive collisions on the quantum level is a main goal of the developing field of ultracold chemistry. For this, the preparation of precisely defined initial atomic and molecular states in tailored environments is necessary. Here we present experimental studies of inelastic collisions of metastable ultracold Rb2 molecules in an array of quasi-1D potential tubes. In particular, we investigate collisions of molecules in the absolute lowest triplet energy level where any inelastic process requires a change of the electronic state. Remarkably, we find similar decay rates as for collisions between rotationally or vibrationally excited triplet molecules where other decay paths are also available. The decay rates are close to the ones for universal reactions but vary considerably when confinement and collision energy are changed. This might be exploited to control the collisional properties of molecules.

Carbazole-diphenylimidazole based bipolar material and its application in blue, green and red single layer OLEDs by solution processing

Single layer structure is an ideal way to realize the low cost solution processed organic light-emitting diodes (OLEDs). Efficient electroluminescent material with hole and electron transport characters as well as suitable triplet energy levels is highly desired to realize single layer OLEDs with good performance. In this work, a bipolar compound with carbazole as electron donor and 4,5-diphenylimidazoleas as electron acceptor has been successfully synthesized and applied as emitting layer for both non-doped and doped single layer OLEDs fabricated by solution processing. A pure blue emission achieved in the non-doped single layer OLED with a current efficiency of 0.38 cd A−1, luminance up to 672 cd m−2. The single layer doped OLEDs with the bipolar compound as host achieved blue, green and red phosphorescence OLEDs with current efficiency of 0.083, 13.42, 2.58 cd A−1 and luminance up to 108, 17103, 1347 cd m−2, respectively. The performance of single layer OLEDs has been greatly improved by bipolar emitting materials which show a great potential to simplify the configuration of OLEDs.

Novel bipolar host for highly efficient green, yellow, orange, red and deep-red phosphorescent organic light-emitting devices

A novel bipolar host tris(4-(pyrimidin-5-yl)phenyl)amine (TPMTPA) constructed by incorporating triphenylamine as the electron-donating core and pyrimidine as the electron-accepting peripheries was designed and synthesized. TPMTPA achieves excellent bipolar charge transport properties and has high enough triplet energy level to sensitize green, yellow, orange, red and deep-red phosphors. By using TPMTPA as a host, high performance green, yellow, orange, red and deep-red phosphorescent organic light-emitting devices (PhOLEDs) were demonstrated with maximum external quantum efficiencies of 20.4%, 17.6%, 15.1%, 15.3% and 15.7% respectively. These results suggested that TPMTPA is a versatile high performance host for PhOLEDs of different emission colors.

Monitoring of the energy levels by heteroatom substitution to hexacene and controlling over singlet fission and photo-oxidative resistance

The singlet fission is a spin allowed and extremely fast internal conversion process involved in solar cell by which a photo-excited singlet exciton is splitted into two triplet ones. For effective singlet fission and to increase the efficiency of solar cell, designing of new molecules is an interesting area of research and our current interest. The silicon substituted oligocenes, commonly known as silaoligocenes, are found to be the efficient singlet fission material due to their special characteristics. We have shown the SF energy criteria satisfied by the singlet and triplet states of various silahexacene derivatives, and theoretically predicted whether such molecules exhibit fission properties or not. The fluorine atoms have been substituted to various positions of different silahexacenes to manipulate their singlet and triplet energy levels. As fluorine being the most electro-negative substituent, it is capable of lowering frontier molecular orbital energies effectively. Thus, the material can easily match SF energy criteria to compute the SF driving force or triplet–triplet annihilation possibility. The geometries, electronic structures, frontier molecular orbital energies, optimization of excited state and calculation of energies associated with fission process of the substituted hexacene are investigated with well known quantum mechanical methods.