Fabrication of Alternating Copolymers Based on Cyclopentadithiophene-Benzothiadiazole Dicarboxylic Imide with Reduced Optical Band Gap: Synthesis, Optical, Electrochemical, Thermal, and Structural Properties

A series of alternating copolymers containing cyclopentadithiophene (CPDT) flanked by thienyl moieties as electron-donor units and benzothiadiazole dicarboxylic imide (BTDI) as electron-acceptor units were designed and synthesized for solar cell applications. Different solubilizing side chains, including 2-ethylhexyl chains and n-octyl chains were attached to CPDT units, whereas 3,7-dimethyloctyl chains and n-octyl chains were anchored to the BTDI moieties. The impact of these substituents on the solubilities, molecular weights, optical and electrochemical properties, and thermal and structural properties of the resulting polymers was investigated. PCPDTDTBTDI-EH, DMO was synthesized via Suzuki polymerization, whereas PCPDTDTBTDI-8, DMO, and PCPDTDTBTDI-EH, 8 were prepared through direct arylation polymerization. PCPDTDTBTDI-8, DMO has the highest number average molecular weight (Mn = 17,400 g mol−1) among all polymers prepared. The PCPDTDTBTDI-8, DMO and PCPDTDTBTDI-8, 8 which have n-octyl substituents on their CPDT units have comparable optical band gaps (Eg ~ 1.3 eV), which are around 0.1 eV lower than PCPDTDTBTDI-EH, DMO analogues that have 2-ethylhexyl substituents on their CPDT units. The polymers have their HOMO levels between −5.10 and −5.22 eV with PCPDTDTBTDI-EH, DMO having the deepest highest occupied molecular orbital (HOMO) energy level. The lowest unoccupied molecular orbital (LUMO) levels of the polymers are between −3.4 and −3.5 eV. All polymers exhibit good thermal stability with decomposition temperatures surpassing 350 °C. Powder X-ray diffraction (XRD) studies have shown that all polymers have the amorphous nature in solid state.

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Characteristics of Low Band Gap Copolymers Containing Anthracene-Benzothiadiazole Dicarboxylic Imide: Synthesis, Optical, Electrochemical, Thermal and Structural Studies

Polymers ◽

10.3390/polym13010062 ◽

2020 ◽

Vol 13 (1) ◽

pp. 62

Author(s):

Ary R. Murad ◽

Ahmed Iraqi ◽

Shujahadeen B. Aziz ◽

Mohammed S. Almeataq ◽

Sozan N. Abdullah ◽

...

Keyword(s):

Band Gap ◽

Molecular Orbital ◽

Energy Levels ◽

X Ray Diffraction ◽

Low Band Gap ◽

Molecular Weights ◽

Highest Occupied Molecular Orbital ◽

Donor Acceptor ◽

Lowest Unoccupied Molecular Orbital ◽

The Impact

Two novel low band gap donor–acceptor (D–A) copolymers, poly[9,10-bis(4-(dodecyloxy)phenyl)-2,6-anthracene-alt-5,5-(4′,7′-bis(2-thienyl)-2′,1′,3′-benzothiadiazole-N-5,6-(3,7-dimethyloctyl)dicarboxylic imide)] (PPADTBTDI-DMO) and poly[9,10-bis(4-(dodecyloxy)phenyl)-2,6-anthracene-alt-5,5-(4′,7′-bis(2-thienyl)-2′,1′,3′-benzothiadiazole-5,6-N-octyl-dicarboxylic imide)] (PPADTBTDI-8) were synthesized in the present work by copolymerising the bis-boronate ester of 9,10-phenylsubstituted anthracene flanked by thienyl groups as electron–donor units with benzothiadiazole dicarboxylic imide (BTDI) as electron–acceptor units. Both polymers were synthesized in good yields via Suzuki polymerisation. Two different solubilizing alkyl chains were anchored to the BTDI units in order to investigate the impact upon their solubilities, molecular weights, optical and electrochemical properties, structural properties and thermal stability of the resulting polymers. Both polymers have comparable molecular weights and have a low optical band gap (Eg) of 1.66 eV. The polymers have low-lying highest occupied molecular orbital (HOMO) levels of about −5.5 eV as well as the similar lowest unoccupied molecular orbital (LUMO) energy levels of −3.56 eV. Thermogravimetric analyses (TGA) of PPADTBTDI-DMO and PPADTBTDI-8 did not prove instability with decomposition temperatures at 354 and 313 °C, respectively. Powder X-ray diffraction (XRD) studies have shown that both polymers have an amorphous nature in the solid state, which could be used as electrolytes in optoelectronic devices.

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Synthesis and Characterization of Fluorene-Based Polymers Having Azine Unit for Blue Light Emission

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.62.21 ◽

2015 ◽

Vol 62 ◽

pp. 21-28

Author(s):

Zhong Min Geng ◽

Masashi Kijima

Keyword(s):

Molecular Orbital ◽

Light Emission ◽

Energy Levels ◽

Average Molecular Weight ◽

Orbital Energy ◽

Good Thermal Stability ◽

Highest Occupied Molecular Orbital ◽

Donor Acceptor ◽

Lowest Unoccupied Molecular Orbital

Two types of donor-acceptor copolymers were designed and synthesized by combination of an electron donor unit of fluorene sequences and an electron acceptor azine unit such as 1,2,4,5-tetrazine and 1,3,5-triazine. They were well soluble in common organic solvents with the number average molecular weight (Mn) of 7.0 and 14.5 kg mol-1, respectively, and have good thermal stability showing about at 360 °C with 5 wt% loss in TGA. Two copolymers exhibited intense blue photoluminescence with emission peak maxima at 437 and 421 nm in CHCl3, and 451 and 422 nm in the film state, respectively. These polymers exhibited good fluorescence quantum efficiencies in CHCl3 (φfl = 0.63, 0.97). Energy levels of the highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels estimated by cyclic voltammetry were to be –5.83, –6.0 eV and –2.85, –2.88 eV, respectively.

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Influence of Fluorine Substitution on the Optical, Thermal, Electrochemical and Structural Properties of Carbazole-Benzothiadiazole Dicarboxylic Imide Alternate Copolymers

Polymers ◽

10.3390/polym12122910 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2910 ◽

Cited By ~ 2

Author(s):

Ary R. Murad ◽

Ahmed Iraqi ◽

Shujahadeen B. Aziz ◽

Hunan Hi ◽

Sozan N. Abdullah ◽

...

Keyword(s):

Thermal Stability ◽

Molecular Orbital ◽

Energy Levels ◽

Average Molecular Weight ◽

Band Gaps ◽

Hydrogen Atoms ◽

Good Thermal Stability ◽

Optical Band Gaps ◽

Fluorinated Copolymers ◽

The Impact

In this work four novel donor-acceptor copolymers, PCDTBTDI-DMO, PCDTBTDI-8, P2F-CDTBTDI-DMO and P2F-CDTBTDI-8, were designed and synthesised via Suzuki polymerisation. The first two copolymers consist of 2,7-carbazole flanked by thienyl moieties as the electron donor unit and benzothiadiazole dicarboxylic imide (BTDI) as electron acceptor units. In the structures of P2F-CDTBTDI-DMO and P2F-CDTBTDI-8 copolymers, two fluorine atoms were incorporated at 3,6-positions of 2,7-carbazole to investigate the impact of fluorine upon the optoelectronic, structural and thermal properties of the resulting polymers. P2F-CDTBTDI-8 possesses the highest number average molecular weight (Mn = 24,200 g mol−1) among all the polymers synthesised. PCDTBTDI-DMO and PCDTBTDI-8 show identical optical band gaps of 1.76 eV. However, the optical band gaps of fluorinated copolymers are slightly higher than non-fluorinated counterparts. All polymers have deep-lying highest occupied molecular orbital (HOMO) levels. Changing the alkyl chain substituents on BTDI moieties from linear n-octyl to branched 3,7-dimethyloctyl groups as well as substituting the two hydrogen atoms at 3,6-positions of carbazole unit by fluorine atoms has negligible impact on the HOMO levels of the polymers. Similarly, the lowest unoccupied molecular orbital (LUMO) energy levels are almost comparable for all polymers. Thermogravimetric analysis (TGA) has shown that all polymers have good thermal stability and also confirmed that the fluorinated copolymers have higher thermal stability relative to those non-fluorinated analogues. Powder X-ray diffraction (XRD) studies proved that all polymers have an amorphous nature in the solid state.

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Optical, Electrochemical, Thermal, and Structural Properties of Synthesized Fluorene/Dibenzosilole-Benzothiadiazole Dicarboxylic Imide Alternating Organic Copolymers for Photovoltaic Applications

Coatings ◽

10.3390/coatings10121147 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1147 ◽

Cited By ~ 2

Author(s):

Ary R. Murad ◽

A. Iraqi ◽

Shujahadeen B. Aziz ◽

Sozan N. Abdullah ◽

Rebar T. Abdulwahid ◽

...

Keyword(s):

Structural Properties ◽

Energy Levels ◽

Average Molecular Weight ◽

Excellent Thermal Stability ◽

Alkyl Chains ◽

Molecular Weights ◽

Photovoltaic Applications ◽

Amorphous Nature ◽

Donor Acceptor ◽

The Impact

In this work, four donor–acceptor copolymers, PFDTBTDI-DMO, PFDTBTDI-8, PDBSDTBTDI-DMO, and PDBSDTBTDI-8, based on alternating 2,7-fluorene or 2,7-dibenzosilole flanked by thienyl units, as electron-donor moieties and benzothiadiazole dicarboxylic imide (BTDI) as electron-accepting units, have been designed and synthesized for photovoltaic applications. All polymers were synthesized in good yields via Suzuki polymerization. The impact of attaching two different alkyl chains (3,7-dimethyloctyl vs. n-octyl) to the BTDI units upon the solubilities, molecular weights, optical and electrochemical properties, and thermal and structural properties of the resulting polymers was investigated. PFDTBTDI-8 has the highest number average molecular weight (Mn = 24,900 g·mol−1) among all polymers prepared. Dibenzosilole-based polymers have slightly lower optical band gaps relative to their fluorene-based analogues. All polymers displayed deep-lying HOMO levels. Their HOMO energy levels are unaffected by the nature of either the alkyl substituents or the donor moieties. Similarly, the LUMO levels are almost identical for all polymers. All polymers exhibit excellent thermal stability with Td exceeding 350 °C. X-ray powder diffraction (XRD) studies have shown that all polymers have an amorphous nature in the solid state.

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Synthesis of Amorphous Conjugated Copolymers Based on Dithienosilole-Benzothiadiazole Dicarboxylic Imide with Tuned Optical Band Gaps and High Thermal Stability

Applied Sciences ◽

10.3390/app11114866 ◽

2021 ◽

Vol 11 (11) ◽

pp. 4866

Author(s):

Ary R. Murad ◽

Elham M. A. Dannoun ◽

Shujahadeen B. Aziz ◽

Ahmed Iraqi ◽

Sozan N. Abdullah ◽

...

Keyword(s):

Thermal Stability ◽

Molecular Weight ◽

Molecular Orbital ◽

Structural Characteristics ◽

Average Molecular Weight ◽

Band Gaps ◽

X Ray Diffraction ◽

Optical Band Gaps ◽

Highest Occupied Molecular Orbital ◽

Lowest Unoccupied Molecular Orbital

Two alternating copolymers of dithienosilole (DTS) were designed and synthesized with small optical band gaps, flanked by thienyl units as electron-donor moieties and benzothiadiazole dicarboxylic imide (BTDI) as electron-acceptor moieties. The BTDI moieties were anchored to two different solubilizing side chains, namely 3,7-dimethyloctyl and n-octyl chains. An analysis of the effect of the electrochemical, optical, thermal, and structural characteristics of the resulting polymers along with their solubility and molecular weight is the subject of this paper. The Stille polymerization was used to synthesize PDTSDTBTDI-DMO and PDTSDTBTDI-8. The average molecular weight of PDTSDTBTDI-DMO and PDTSDTBTDI-8 is 14,600 and 5700 g mol−1, respectively. Both polymers have shown equivalent optical band gaps around 1.4 eV. The highest occupied molecular orbital (HOMO) levels of the polymers were comparable, around −5.2 eV. The lowest unoccupied molecular orbital (LUMO) values were −3.56 and −3.45 eV for PDTSDTBTDI-DMO and PDTSDTBTDI-8, respectively. At decomposition temperatures above 350 °C, both copolymers showed strong thermal stability. The studies of powder X-ray diffraction (XRD) have shown that they are amorphous in a solid-state.

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Electronic Properties of Triangle Molybdenum Disulfide (MoS2) Clusters with Different Sizes and Edges

Molecules ◽

10.3390/molecules26041157 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1157

Author(s):

Songsong Wang ◽

Changliang Han ◽

Liuqi Ye ◽

Guiling Zhang ◽

Yangyang Hu ◽

...

Keyword(s):

Quantum Chemistry ◽

Electronic Properties ◽

Absorption Spectra ◽

Molecular Orbital ◽

Electronic Structures ◽

Edge States ◽

Frontier Orbitals ◽

Edge Structure ◽

Highest Occupied Molecular Orbital ◽

Lowest Unoccupied Molecular Orbital

The electronic structures and transition properties of three types of triangle MoS2 clusters, A (Mo edge passivated with two S atoms), B (Mo edge passivated with one S atom), and C (S edge) have been explored using quantum chemistry methods. The highest occupied molecular orbital (HOMO)–lowest unoccupied molecular orbital (LUMO) gap of B and C is larger than that of A, due to the absence of the dangling of edge S atoms. The frontier orbitals (FMOs) of A can be divided into two categories, edge states from S3p at the edge and hybrid states of Mo4d and S3p covering the whole cluster. Due to edge/corner states appearing in the FMOs of triangle MoS2 clusters, their absorption spectra show unique characteristics along with the edge structure and size.

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Photoconductivity of Low-Bandgap Polymer and Polymer: Fullerene Bulk Heterojunction Studied by Constant Photocurrent Method

Organic Photonics and Photovoltaics ◽

10.1515/oph-2015-0011 ◽

2015 ◽

Vol 3 (1) ◽

Cited By ~ 2

Author(s):

V. V. Malov ◽

A. R. Tameev ◽

S. V. Novikov ◽

M. V. Khenkin ◽

A. G. Kazanskii ◽

...

Keyword(s):

Molecular Orbital ◽

Bulk Heterojunction ◽

Inorganic Materials ◽

Fullerene Derivative ◽

Approximation Procedure ◽

Photoelectric Properties ◽

Highest Occupied Molecular Orbital ◽

Donor Acceptor ◽

Lowest Unoccupied Molecular Orbital ◽

Doped Polymers

AbstractOptical and photoelectric properties of modern photosensitive polymers are of great interest due to their prospects for photovoltaic applications. In particular, an investigation of absorption and photoconductivity edge of these materials could provide valuable information. For these purpose we applied the constant photocurrent method which has proved its efficiency for inorganic materials. PCDTBT and PTB7 polymers were used as objects for the study as well as their blends with a fullerene derivative PC71BM. The measurements by constant photocurrent method (CPM) show that formation of bulk heterojunction (BHJ) in the blends increases photoconductivity and results in a redshift of the photocurrent edge in the doped polymers compared with that in the neat polymers. Obtained from CPM data, spectral dependences of absorption coefficient were approximated using Gaussian distribution of density-of-states within HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) bands. The approximation procedure allowed us to evaluate rather optical than electrical bandgaps for the studied materials. Moreover, spectra of polymer:PC71BM blends were fitted well by the sum of two Gaussian peaks which reveal both the transitions within the polymer and the transitions involving charge transfer states at the donor-acceptor interface in the BHJ.

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Estudo do comportamento óptico-estrutural do LiNbO3

Cerâmica ◽

10.1590/s0366-69132003000100008 ◽

2003 ◽

Vol 49 (309) ◽

pp. 36-39 ◽

Cited By ~ 1

Author(s):

C. D. Pinheiro ◽

V. Bouquet ◽

F. M. Pontes ◽

E. R. Leite ◽

E. Longo

Keyword(s):

Molecular Orbital ◽

Highest Occupied Molecular Orbital ◽

Lowest Unoccupied Molecular Orbital

Realizou-se um estudo teórico-experimental sobre as estruturas cristalina e amorfa de niobato de lítio, para verificar a influência dos defeitos sobre as propriedades ópticas desse semicondutor. Filmes finos cristalinos de LiNbO3 (c-LN) e amorfo (a-LN) foram preparados pelo método dos precursores poliméricos, sendo caracterizados por difração de raios X e microscopia de força atômica. As propriedades ópticas foram estudadas por UV-Visível e espectroscopia Raman. Em particular, o filme amorfo apresentou luminescência, cuja posição do pico varia de acordo com o comprimento de onda de excitação. A diferença de energia entre os níveis HOMO (Highest Occupied Molecular Orbital) e LUMO (Lowest Unoccupied Molecular Orbital) revela que o gap de banda da fase cristalina é maior que aquele exibido pela fase amorfa, em acordo com os dados experimentais de UV-visível. Observou-se o surgimento de novos níveis eletrônicos na região do gap de banda na estrutura amorfa, este fato pode explicar as propriedades ópticas particulares observadas sobre o filme amorfo.

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Synthesis and characterization of oligo-4-[(pyridin-3-ylimino)methyl]phenol

Chemical Papers ◽

10.2478/s11696-007-0020-9 ◽

2007 ◽

Vol 61 (3) ◽

Cited By ~ 2

Author(s):

İ. Kaya ◽

S. Çulhaoğlu ◽

D. Şenol

Keyword(s):

Molecular Orbital ◽

Thermal Analyses ◽

Size Exclusion ◽

Degradation Temperature ◽

Highest Occupied Molecular Orbital ◽

N2 Atmosphere ◽

Exclusion Chromatography ◽

N Doping ◽

Lowest Unoccupied Molecular Orbital ◽

Optimum Reaction

AbstractThe oxidative polycondensation of 4-[(pyridin-3-ylimino)methyl]phenol (4-PIMP) with O2, H2O2, and NaOCl was studied in an aqueous alkaline medium between 50°C and 90°C. Oligo-4-[(pyridin-3-ylimino)methyl]phenol (O-4-PIMP) prepared was characterized by 1H-NMR, 13C-NMR, FT-IR, UV-VIS, size-exclusion chromatography, and elemental and thermal analyses techniques. At the optimum reaction conditions, the yield of O-4-PIMP was 18.9%, 39.4%, and 46.8% using H2O2, O2, and NaOCl oxidant, respectively. According to the TG analysis, the initial degradation temperature of O-4-PIMP was 218°C, which was by 50°C higher than that of 4-PIMP. Thermal analyses of 4-PIMP and O-4-PIMP were carried out in N2 atmosphere at 15–1000°C. The highest occupied molecular orbital, the lowest unoccupied molecular orbital, and electrochemical energy gaps of 4-PIMP and O-4-PIMP were determined from the onset potentials for n-doping and p-doping, respectively. Also, optical band gaps of 4-PIMP and O-4-PIMP were determined according to UV-VIS measurements.

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QTAIM investigation of bis(pyrazol-1-yl)methane derivative and its Zn(II) complexes (ZnLX2, X=Cl, Br or I)

Journal of the Serbian Chemical Society ◽

10.2298/jsc150224027z ◽

2015 ◽

Vol 80 (8) ◽

pp. 997-1008 ◽

Cited By ~ 3

Author(s):

Maryam Dehestani ◽

Leila Zeidabadinejad

Keyword(s):

Molecular Orbital ◽

Critical Points ◽

Structural Parameters ◽

Frontier Molecular Orbital ◽

Orbital Energy ◽

Theory Approach ◽

Topological Parameters ◽

Molecular Orbital Energy ◽

Highest Occupied Molecular Orbital ◽

Lowest Unoccupied Molecular Orbital

Topological analyses of the electron density using the quantum theory of atoms in molecules (QTAIM) have been carried out at the B3PW91/6-31g (d) theoretical level, on bis(pyrazol-1-yl)methanes derivatives 9-(4-(di (1H-pyrazol-1-yl)-methyl)phenyl)-9H-carbazole (L) and its zinc(II) complexes: ZnLCl2 (1), ZnLBr2 (2) and ZnLI2 (3). The topological parameters derived from Bader theory were also analyzed; these are characteristics of Zn-bond critical points and also of ring critical points. The calculated structural parameters are the frontier molecular orbital energies highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO), hardness (?), softness (S), the absolute electronegativity (?), the electrophilicity index (?) and the fractions of electrons transferred (?N) from ZnLX2 complexes to L. The numerous correlations and dependencies between energy terms of the Symmetry Adapted Perturbation Theory approach (SAPT), geometrical, topological and energetic parameters were detected and described.

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